I'm Rich Daley, head of sales for the webinar vet, and I'm pleased to welcome you all here this evening. Tonight our speaker is, is, is Elisabetta Manchinelli, sorry, and Elisabetta graduated from the University of Naples, Federico II in Italy in 2002. Her interest in exotics became clear shortly after her graduation, anticipating a career mainly based on non-conventional animal medicine and surgery.
After a small animal focused internship, she's been working solely with exotics since 2003. She undertook an externship in France, mainly based on reptile medicine and then completed an externship programme at the Angel Animal Memorial Hospital in Boston. Focusing on exotic animal medicine and surgery.
In 2007, she moved to the UK where she initially worked in private practise and wildlife charities. And in 2009, Elizabeth has started the first European College of zoological medicine residency and small mammal medicine, which she completed at the Royal Dick School of Veterinary Studies. And then following that, from September 2010, she held the RCVS certificate in zoological medicine.
In 2014, Elizabetta obtained the ECZM diploma specialty in small mammal medicine and surgery. She currently leads the exotic department at High Croft Veterinary Referrals in Bristol. So before I hand over to Elizabetta, we will be taking questions at the end, so please do post your questions in the Q&A box.
If any of you are new to our webinars, at the bottom of the page you will see that it says Q&A. Please do click on that and then you'll be able to type the questions and we'll come back to them at the end. I'm supported tonight by my colleague Lewis, who's there to help with any technical issues.
So if you do have any technical issues at all, please do enter your query in the chat box and Lewis will respond to you very shortly. So without further ado, I'd like to hand over to Elizabetta. Welcome.
Thank you very much for your kind introduction and welcome everyone. Thank you very much for joining tonight. Tonight's webinar will be about guinea pigs because guinea pigs are becoming one of the most popular pet rodents within the UK and the clients are definitely becoming increasingly demanding, expecting knowledge and exceptional quality care for their pets.
Never underestimated the emotional attachment to the many of these owners who will laugh towards these. Little creature, especially when it comes to demand in terms of medical and sometimes surgical treatment. However, on the other hand, inappropriate diet and husbandry are often responsible for many of the common disorders that we see in these pet animals.
Now, according to one study, dental disease, skin disorder, and ovarian cystic disease are among the most common conditions reported in this species. However, according to For another study, there seem to be mismatch between the conditions that are considered common by the veterinary profession and those that are actually reported in the literature. And the other thing to consider is also that guinea pigs are prey species and they are masters, probably even more the rabbits are disguising signs of illness and leading many owners to conclude that they do expire quickly, suddenly with no apparent reason.
However, when veterinary intervention is sort it usually Because the animal is in a very critical or even a more even state. It is important to remember though that certain conditions can be treated and especially if clinical signs are picked up early, then the treatment is actually possible and a positive outcome is, is definitely a possibility. Now, guinea pigs are very often presented for general, you know, a variety of conditions and tonight, obviously, having available only one hour, we cannot go through all of them.
So we'll take into consideration what I think are some of the most common ones, and some of the most interesting ones, and some of the ones that we are getting gradually to know and they're more easily diagnosed now than in the past. Now, the first thing to consider is that anorexia is probably one of the common presenting complaint from guinea pig's owner. However, anorexia is not a disease.
There are many possible causes from metabolic diseases to systemic infections, meaning that in the majority of cases, or I would say all of these cases. Guinea pigs that needs to be, appropriately worked up. So a diagnostic workup is absolutely essential to be able to identify the primary cause responsible for inhapetence.
Now, consider that, a lack, there are several conditions that will need to be taken into consideration from easy things, such as a sensitivity to dietary changes. Guinea pigs are quite, adjust to their routine and any little change may cause, you know, issues to them, but they also can develop gastrointestinal tract. Stasis from food infections and bedsores.
A lack of vitamin C also may lead to painful joints, mastications, and therefore anorexia and metabolic diseases of any type, certain systemic diseases as well, or any type of pain from photodermatitis to dental disease lysis can ultimately induce. Now unfortunately, often you know it's not possible to detect the true cause of anorexia, weight loss in the antemortem guinea pig. However, as we said, all these cases should be fully investigated and should have a list of full body and the skull radiographs, a blood sample, and potentially a urine analysis as well.
In absence of a primary cause for the anorexia treatment remains supportive and it should include replacement fluid considering that. Maintenance rates for guinea pigs have been estimated between 180 and 100 mL per kg per day. Vitamin C supplementations, as we know, the guinea pigs are not able to synthesise vitamin C by themselves, and force feeding, there are several supportive feeding formulas available for anorective guinea pigs, and obviously analgesia is extremely important whenever is is required.
Now, the first thing that we'll take into consideration is dental disease. So dental disease because it is very common, it's very difficult to identify, especially in early stages, and probably guinea pigs are the most complicated of all rodents in terms of dental changes. Now, rodents are a vast group of animals that comprises about 40% of all mammals in the world.
Now, a large group that comprises animals of different amount of physiology, different habits, different feeding strategies as well. Now, in terms of classic. And this large group is usually subdivided into suborders according to the anatomical and physiological characteristic of the yo masceteric system, which is the anatomic arrangement of the mastar muscle as compared to a certain portion of the skull.
Now, according to this, three different borders are identified. The porcupine-like rodents, which includes the guinea pigs, chinchillas, and da, rat-like rodents, which includes rats, mice, and gerbils, for example, and squirrel-like rodents, which includes squirrels and prairie dogs, for example. Now, why this is important to to to remember because these, these characteristics.
Reflects into their feeding habits. For example, guinea pigs are characterised by an enlarged zygomaticomandibular portion of the mastar muscle which originates on the front edge of the zygoma of the skull and the superficial portion of the muscle muscle is responsible for moving the mandible backward and forward while the deep portion. Of the muscle the muscle is able to adjust the the the jaw closing the mouth.
This is important because differently from other subboard results in an effective grinding action of the molars as compared to different anatomical arrangements that will result in a more effective action of the incisors, for example, which is related to the different food items that are consumed by those rodents. So this is a very important consideration because the normal dental anatomy of rodents and in particular guinea pigs closely relates to their feeding habits. Now, the division of the muscular muscle in guinea pigs allows the guinea pigs to perform a particular movement of the jaw, which is combined rostrocaudal and lateral or better diagonal.
That's why we say normally that guinea pigs have a proper lineal chewing motion of their jaws, so their jaw movements are diagonal. Now, in terms of dentition, it is extremely important to remember that guinea pigs have monophydon teeth. It means that they lack, they lack the deciduous part of the teeth so they only have permanent teeth.
They have heterodont teeth with different shape, think obviously of incisors and molars. They have elodon teeth which are continuously growing and erupting throughout the guinea pig's life. They are radicular, so they do not have anatomical roots like for example, dogs or cats.
They are ipsodonts or long crowned teeth, and they lack pet teeth differently, for example, from lagomorphs, so, for example, rabbits. Guinea pigs, as you can see from these anatomic specimens are anisoattic, meaning that the mandible is wider as compared to the maxilla, but also these anatomic specimens shows which is probably the most important of the anatomic features in terms of dental. Anatomy of this species, which is the curvature of the teeth which results in a bent occlusal plane about 30 degrees.
This is extremely important because if you remember, for example, rabbits have an almost horizontal occlusal plane in this species, a 30 degree occlusal plane results in a series of implications of the clinical and diagnostic and therapeutic. Now, dental disease, as we said, can be very difficult to identifying guinea pigs. Symptoms are often non-specific, guinea pigs with dental disease and may be presented for reduced food intake to anorexia, digestive disturbances, weight loss, there may be evident chewing difficulties, the typical guinea pig, for example, that is actually interested in food but drops the food that is not able to choose or choose slowly as compared.
To normal incisor mluclusion may be immediately evident and it is important to remember that in guinea pigs, the primary incisor maloclusion, also not of traumatic origin, is actually, rare, and, incisor mluclusion is actually generally secondary to changes of the teeth and facial swelling, so when, for example, dental disease has resulted in complications such as facial abscesses of periodical origin. Now, dental disease can be quite challenging in this species, in terms of pathogenesis, unfortunately, we don't know very much about it in this species. Metabolic bone disease has not yet been described as a cause for dental disease in this species, and it looks like that diet infections and trauma seem to play play a major role in the development of this condition in these species.
Now, a definitive diagnosis can be quite complicated. Oral exam performed in a conscious animal is usually very difficult because guinea, most guinea pigs have a mouth full of food and early changes especially can be very difficult to pick up. Therefore, a definitive diagnosis can only be achieved by a combination.
Of oral examination under anaesthetic, stomatoscopy, the use of a region endoscopy to evaluate the mouse actually greatly enhances the possibility of identifying early changes. Radiography, CT and MRI obviously further enhance the possibility of detecting abnormalities in these species. Now, if you see here, there is a full set of s called radiographs which should always be taken when trying to rule out or identify dental changes which include one lateral, either right or left, the two obliques, one right and one left, a dorso denral or ventral dorsal and in this species of the cranial caudal view, which is the one that you can see at the bottom in the centre.
Of the screen, which is probably one of the most informative ones because if you can see from the lateral picture, so the first one on the left side of the screen, it actually doesn't give you much information about the elongation of the cheek teeth, especially in early stages of disease, may give some information about maloclusion of incisors, but doesn't give much information about the occlusal surface of, of the teeth. Information which instead can be detected from the cranial caudal view which gives an exact idea of the presence of scars, for example, bridges over the Tonga, which is one of the most common type of dental changes seen in these pieces, and also gives information about the temporal mandibular joint, which is one of the things that can further complicate dental changes in severe cases in in these species. Now, in terms of treatment, Treatment follows directions already published for other species, so depending on what degree of dental disease we have, corona reduction of the cheek teeth or incisors or both may be performed.
Teeth extractions may be required whenever infection. Is present and after surgery may obviously be necessary when the complication arise and follow exactly the same principles that have been already published, for example, for rabbits simply applied to a different species. If we go on with the with our diseases, the next, next one I would like to discuss about regards, still the gastrointestinal tract but with more interest to the gastrointestinal system, so, I would like Discuss about the gastrointestinal hypomotility of stasis and another condition that is still under discussion in a way in the sense that there is not so much known about this which is gastric dilation volveus in in Guinea pigs.
Now, gastrointestinal stasis is extremely common in this species. It is a secondary to virtually any disease potentially causing pain or anorexia in guinea pigs. Inadequate fibre content also can represent a significant predisposing factor potentially leading to a GI Ipomotility, dehydration of GI content, and stasis.
The clinical signs may include decreased or absent faecal output, anorexia, abdominal pain, hunched posture, distended stomach or bowel loops, and reduced sounds. The GI content may become dehydrated, further exacerbating pain and anorexia and potentially leading to partial or complete gastrointestinal obstruction. But what it is important to remember if gastrointestinal is so common, is also that it can result in the accumulation of a large amount of gas within the stomach and intestine and because guinea pigs cannot vomit or irritate, gastric dilation and blood can occur, which may become life threatening in some cases.
Now, it is important to distinguish between gastric stasis and gastric dilation vulus because these can present with exactly the same clinical signs. Now, gastric dilation vulvus is being reported in guinea pigs, although very recently, potential predisposing factors that have been discussed and may include pregnancy, for example, inappropriate feeding, stressful environment, frequent repositioning during anaesthesia, whereas the shape of the thoracic cavity, which seems to affect the development of gastric bubbles in dogs as well as other anatomic abnormalities are not known to be associated with this condition in, in this species. And a recent report also suggests that Gastric vulus in guinea pigs may develop secondary to conditions which result in delayed gastric emptying such as gastric stasis disorder, and that's why it's extremely important to identify this problem at an early stage and we'll see why as well.
Now, the rotation of the stomach in guinea pigs can result in functional obstruction of the esophageal and or pyloic sphincters and it's associated with pronounced gastric distension with gas. So if you had, for example, a guinea pig presented as the one that you can see in the picture, so with extreme distension of of the abdomen, you will not be able to distinguish based simply on clinical examination of which of the two conditions it is. However, it is an extremely important distinction because a clinical, gastric stasis may be medically resolved, whereas gastric dilation valve theism may become a surgical emergency.
So in terms of symptoms, as we said, these are similar to those seen in gastric stasis. It may include abdominal distention which may become tympanic in a with a tympanic abdomen, respiratory distress when the large stomach presses on the diaphragm compromising the breathing, anorexia, lack of faecal output, lack of gut sounds, and unfortunately in many cases sudden death. Now, in terms of rotation of the stomach, several degrees of rotation have been reported from 360 degrees to one case of 540 degrees rotation.
And you can imagine how the consequences of this can be extremely severe because as in dogs, it can, the rotation of the stomach can result in venous obstruction and production of endotoxins when the torsion of the stomach and the mesentery roots occur. Now, as we said, the history, clinical signs, abdominal palpation and may be indicative of the condition, but radiographs obviously allow a more immediate to more an easier diagnosis. Now, on palpation again, it is important to remember that Differently to a normal guinea pig, which may have a stomach completely full, especially after a large meal but soft and compressible, a guinea pig presented with suspected gastric dilation or GDV may have a stomach full and firm but not compressive.
On radiographic image, as you can see here from the screen, in cases of gastric dilation, you will have a stomach which will appear full and over extended and usually with a gas bubble evidence but with a normal amount of gas in the rest of the gastrointestinal tract. The radiographic appearance of the gastric bulbules instead may vary depending with the with the degree of rotation present. However, usually, as you can see in the image here, there is a large gas distended structure which is filling more than 50% of the abdominal cavity and when mesentery torsion or vulvalos occure, the stomach will be either on the Right side of the body or caudal to a small intestinal loop.
So you can see in this picture in this radiograph how the stomach is is occupying more than 70% of the abdominal cavity and cranial to the stomach, there seem to be a gas distended intestinal, intestinal lobe. Now, obviously, the, this, this condition must be considered an immediate emergency and usually as a very poor prognosis. However, report exists of a successful surgical correction of gastric dilation and boss with gastropexy.
Now medical management can be attempted, especially in cases of gastric dilation and must include a aggressive supportive care, including replacement intravenous fluid therapy. Normal daily water intake in guinea pigs is estimated approximately 100 mL per kilo, and the supplemental fluid requirement should be calculated based on the estimation plus. Additional fluids to compensate for dehydration or fluid loss.
Gastroprotectants may be considered and actually should be considered because gastric dilation and vululus may result in necrosis, for example, whereas prokinetics should be avoided because a partial or complete obstruction is generally presented in the majority of these cases. Obviously, analgesia is of utmost importance because as you can imagine. This condition can be will be extremely painful and gastric decompression definitely should be attended in any case of gastric dilation and possibly bus because it is possible to still try and pass a large pore catheter through through the tors stomach.
Now, in terms of, how to perform the gastric decompression, a tube is passed through the oral cavity, making sure not to obstruct the glottis, after in pre-measuring, the, the tube from the commission of the mouth to, to the last rib, and then the syringe is attached and fluid aspirated. Now consider that in many cases. The content will be semi-solid, a semi-solid mat to ingested, so it may be difficult to aspirate.
So in some cases, the distal part of the tube that may be perforated or cut to allow a better aspiration of of stomach content. Now, as you can see in this image, a large amount of fluid content in other cases can be aspirated. However, as a general rule, it is extremely important to palpate very gently the stomach to determine the pressure that has been relieved.
It is not recommended as a general rule to completely empty the stomach, whereas This procedure should be performed to release the gas and the distension of the organ. Obviously following the procedure, free therapy and medical management can be used to further resolve the abnormalities present. The patient then should be followed radiographically as you can see, this is the image post.
Aspiration of the stomach content and should be kept hospitalised for at least 24, 48 hours or at least the faeces until the faeces are being produced and the patient is no longer descended. However, unfortunately, in many cases, guinea pigs with gastric displacement of Mesoteric vulus are often euthanized as the prognosis is very grave. Now, in, in many cases where the gastric ululus is present, the surgery should be indicated as an emergency procedure, but many of these patients are in, in a very critical, condition, so often they do not survive the, the anaesthetic itself.
. Now, the next, the next, condition that I would like to take into consideration is probably one of the most common ones that you will have to deal in, in practise, and it is eurolithiasis. This disease most commonly affects, middle age to all the guinea pigs. Generally, pigs presented with these problems are over 2.5 years, so all the weather stones can be found in a much younger guinea pigs as well.
Stones may be found anywhere along the urinary tract from the urethra. If you can see these images are both from a female, however, urethral stone may be found in males as well. Stones may be found in the seminal vesicles of male, seminal vesicles, just to remind you are part of the, sexual reproactive glands of, of males.
They're not common. Stones within these seminal vesicles, but they can be seen. Bladder stones are probably the most commonly found ones, and a case of urethral diverticulum with an intraluminal urolith has also been reported.
Now, obviously stones may also be found in the kidney, in the kidneys and in the ureter. Now, a study found unequal distribution of urinary calculi between males and females older than the two years, but those located in the distal ureters especially were predominantly seen in male animals. They then they couldn't see or identify reasons why this, this would happen or why there would be such a sex predilection.
Some authors also consider Peruvian guinea pigs, so to have a higher predisposition to develop eurolithiasis compared to other breeds, however, this is not been yet confirmed. Now, many reports exist in the literature regarding neurolithiasis, but it's, hexopathogenesis still remains unclear, although the alkaline pH and the high mineral content of normal guinea pigs. May seem to favour crystal formation and precipitation.
Now, several risk factors contributing to these conditions have been identified and include inadequate water intake, urine retention, inadequate cage hygiene, obesity, lack of exercise, food items with a high mineral content, renal disease, vitamin or mineral supplementation. Now diet in particular seems to play a major role in terms of especially calcium oxalate content as main risk factors in stone formation. In a study that looked into risk factors associated with the development of neolithiasis, affecting guinea pigs were more likely to be fed a diet high in overall percent pellets, low in percent high, and with a lesser variety of vegetables and fruit.
Now, calcium-containing stones such as the calcium oxalate and calcium carbonate are in fact, are the ones most commonly reported more recently data seem to suggest that calcium carbonate calculi are actually overwhelmingly overwhelmingly present. Infections and mechanical factors may also predispond to stone formation and it's important to consider that that as well. Now, in terms of clinical presentations, symptoms generally depend on the size and locations of the stones.
Now, hematuria, sturia, dysuria may be seen especially in guinea pigs with cystic or urethral calculi. More common clinical signs may reflect generally abdominal pain such as hunched posture, teeth grinding, non-specific signs of disease such as anorexia, lethargy, and weight loss, and if you remember the first slide about anorexia, an anorexic. Guinea pigs or simply presented with this no specific sign may have stones, so it's always important to rule them out.
Now these symptoms, especially those regarding the abdominal pain are often seen when calculi are higher in the urinary tract. Now, although presentation may be acute, it's important to remember that usually these signs have been progressing over days to weeks in affective rodents. So, generally, the presentation is acute, but the condition is, is chronic.
If you see these, the images are simply 3 cases of urosis with a more or less severe, immaturia. Now, what it is important to remember as well, especially in females, is that immaturia may have different origin. Now, differently from rabbits in which the urethra opens within the vagina and therefore a material cannot be distinguished whether it's originating from the urinary or reproductive tract in rodent and guinea pigs, obviously, this is different because the urethral opening and the vaginal opening are separate, meaning that blood coming or blood identified during a clinical examination may be in.
Immediately identifying the organ from where the actual blood is coming. So eurolith is maybe suspected simply based on a clinical evaluation. So in a female, where the blood is coming from the middle part of the perineal area where the vaginal opening is always considered reproductive problems such as cyst ovarian neoplasia or uterine neoplasia as well.
Now, in terms of history, now a detailed history is obviously extremely important because it may direct towards a problem. Detailed the history should include dietary information as well. It is extremely important to ask the owner, not just the diet that is provided to the animal but also what the animals favour.
A complete physical examination is of utmost importance, as we said, a maturia may be immediately evident and it may be difficult, it may be easy, sorry, to identify from the physical examination where that blood is coming from. So eurolithias is or should be suspected in any rodents with changes in the urinary output and with non-specific signs of illness. Now, a definitive diagnosis obviously implies some laboratory testing and imaging modalities as well.
Now, a urine sample and a blood sample should be collected and to rule out the kidney involvement or the concurrent presence of infection, laboratory findings may reflect a high calcium diet, so hypercalcemia may be evident or evidence of cystitis, for example. Now, in a study regarding the specific gravity of guinea pigs with urinary calcula, it was found that the range was actually massively high and the urine pH was found between 8.4 plus or minus 0.5 so by alkaline.
On sediment examination, immaturia may be present, and mucus and lipid droplets as well can be seen. Crystals type more commonly seen on sediment examination include calcium carbonate, oxalate, and struvite. Whether, as in other species, crystals identified on the urine sediment examination are not predictive of the urinary calculate composition and this applies to guinea pigs as well.
Culture of the urine, if collected obviously in a sterile way and prior to antibiotic usage should always be performed, and, it can be useful because obviously it can direct towards the most appropriate antibiotic choice when the sediment examination reveals the presence of bacteria, red and white blood cells. Abdominal radiographs are also valuable because the majority of urinary calcul and guinea pigs are radioaic and obviously are immediately visible from, from the X-ray. You can see these are the image here, there is a large stone in the distal urethra.
This is obviously a female. However, ultrasonography is probably an adjunct imaging modality to to radiography because it can help confirm a presumptive dinosis made using radiograph. It may be necessary to further localise the stones when they are localised in the urethra or in the ureter as well or in the kidneys.
Consider that often when one single view is taken, the, the stones may be mistakenly localised within the bladder where actually they are localised in the distal ureter just have the connection with the bladder, so ultrasonography. Actually allows the exact identification of the location of the stones as well, ultrasonography allows evaluation of changes within the kidneys as well as the bladder or ureter, such as, for example, hydronephrosis, hydroureter as in the image that you see here on the screen, mucosal inflammation or other abdominal or non-urinary pathologies. Now, an extra, intravenous kilogramme may be performed to further evaluate from a functional point of view, the urinary tract or alternatively detailed images can be obtained with a CT scan and with the use of a contrast agent to identify further functional abnormalities.
Another imaging, another modality or another diagnostic tool is extremely, extremely useful, maybe cystoscopy. Cystoscopy, you can see here the use of 2.7 rigid endoscope for direct visualisation of the mucosal surface of the urethra and urinary blood can be extremely helpful.
It allows also to obtain biopsies of mucosal lesions, and in, in case of a very small stones, usually less than 6 millimetres, it also allows removal of the stones from, from the bladder. Now, therapy can be quite challenging because it includes a combination of, or better, challenging and mostly unrewarding because, considering the fact that the pathogenesis of this condition in guinea pigs, so the exact mechanism for stone formation is not known, clear direction for prevention and dissolution of calcui cannot be given. And that's why surgical removal of the calculus is considered the treatment of choice, whereas the medical treatment is obviously necessary but often unrewarding and ineffective at completely resolving the issue.
Also consider the recurring, recurrence of the condition. On the calculator has been surgically removed is very high and these should always be discussed with with the on. Now, dietary modification, vitamin C supplementation, supportive and symptomatic treatment are obviously essential part of the medical management.
In those cases where surgery is obviously performed, and in those cases where the owners decide not to go ahead with the surgery. In the majority of cases where guinea pigs are not. Obstructed, the animal should be stabilised and the surgery appropriately planned.
Now, in terms of we discussed already the cystoscopic removal, which is very useful because it avoids a surgical procedure and it can be obviously less traumatic than a surgery, but it is only possible when stones are of small diameter. But surgical, the surgical option remains the most viable one that will actually eliminate and remove completely the stone. The type of surgical procedure will obviously depend on the localization of the stone.
A erythrotomy may be performed to facilitate the removal of the stones localised in the distal urethra. In some cases, inflammation causes complete attachment of the. Stone to the wall of the urethra.
Therefore, single muscle, incision can allow, you know, the removal of, of the stone in this area. Cystotomy is probably, the easiest of all the procedure is done as routine using techniques described for other species and in cases where stones are localised in the distal urethra, a ureterotomy may be performed or whether. It is always recommended to try and milk this stone into the bladder and then perform a cystoomy rather than ureterotomy because complications of this procedure are high, including stricture, for example, leakage, and, obviously, a risk of damaging the, the ureter.
So we passed to the next the next condition, we got to the, obviously taken into consideration the reproductive tract of guinea pigs and in particular of the female guinea pig. Now, ovarian cysts are being reported to affect between 66 to 75% of females between 3 months and 5 years of age. Variances are classified either according to their causes of physiologic infectious or neoplastic or according to their anatomical origin in relation to the ovary.
Now, in guinea pigs, the majority of cysts are seem to arise from the re ovary. Which is a normal structure of adult female mammals are characterised by a complex network of tubules and cords that arise from the mesoephrine. So they are zerosis which are found in about 63.5% of cases and are therefore intra-ovarian and physiologic.
Ovarians seem to occur throughout the reproductive cycle of guinea pigs and appear to be nonfunctional, so not able to produce hormones. Now, according to studies, there is no correlation between the occurrence of ovarian cysts and the reproductive history of the affected animals. However, there seem to be a correlation between the age, prevalence, and the size of the cysts.
In a smaller percentage of cases, so about 22.4%, the cysts are of follicular origin and are considered steroidogenic, so able to produce hormones. About 1 in 85 cases of diseases are para ovarian.
Now, regarding the pathogenesis of this condition, unfortunately, we don't know much about it. There have been several theories proposed to explain the origin of the different types of seeds from the different area of the ovary of guinea pigs, however, the majority still remains speculations and no further studies have been performed to investigate further the potential yeast link with the development of ovarian cysts in in this species. Now, the clinical presentation can vary widely depending on the type, size, and distribution of the cysts.
Cysts of the radial bodies or serious cysts, as we said, are thought to be non-steroidogenic and therefore guinea pigs may be presented simply with abdominal distention in some cases or simply the cysts may be detected on abdominal palpation, whereas follicular cysts can produce steroids and this can Affect the history, symptoms and clinical signs because frequently guinea pigs are presented with non-pruritic symmetrical alopecia of the lumbosacral flank and you know areas which is to result from the catabolic effect of the oestrogen produced by the steroidogenic follicular or neoplastic ovarian cysts. In, in other cases, when cysts especially become very large, marked abdominal distention may be seen. The guinea pigs may be asymptomatic in some cases, but as the cysts enlarged, causing compression of the abdominal organs, the symptoms arise including those related to pain, for example, such as hunched posture or teeth grinding, reduced appetite to anorexia and obviously in these cases, cysts are very readily palpable.
Now, in cases of singular lopecia, obviously, it is important to consider differential diagnosis in these species and where some of these conditions are more or less rare. In terms of the diagnosis, history and physical examination are usually strongly suggestive of ovarian cystic disease. Haematology, biochemistry, and urine analysis changes that may not be immediately useful for a definitive diagnosis, but obviously are necessary for evaluation of the general health, the general clinical condition of the animal, especially in consideration.
Then all the possible surgical intervention, hormonal SAs are generally considered not reliable because cysts may or may not be steroidogenic and serum oestrogen and progesterone may be normal even when the, when the cysts contain high level of these, the, the fluid contained within the cyst contains high level of these hormones. Radiography may be nonspecific in identifying ovarian cysts because the radio opacity of the cyst is usually similar to that of soft tissue masses or triobedos. Therefore, Ultrasonography is probably considered the imaging modality of choice of for definitive identification of cysts in this species.
Cysts are generally variably sized, anechoic, uni or multilocular and filled with a variable amount. Of fluid. They are contiguous with the ovaries and also to the kidneys.
Obviously considered that neoplastic cysts with a cystic appearance may be present and may be seen as solid masses with variable ecogenicity. Ultrasound guided the fine needle aspirating cytology of disease content can be performed. However, the majority of authors do just cushion a caution when performing this procedure because it may potentially result in a rupture of the cysts and potential peritonitis which may be septic or aseptic.
It can also result in haemorrhage and tumour cell seeding in case of neoplastic cysts. In terms of the treatment, because of these cysts may be derived from different anatomy structures, this obviously result or may affect the treatment options and recommendations. Now, Ovariosterectomy is generally considered the treatment of choice and is usually curative.
Although, especially in presence of large cysts and because of the specific anatomy of guinea pigs, surgery can be quite challenging. Ovareectomy alone is generally not recommended as a treatment because of the likely association of this condition with uterine disease, however, preemptive ovarectomy in animal and there is no study so far to identify the exact age at which this procedure should be performed, generally, anecdotally is reported between 4 to 6 months can be performed to obviously prevent the risk of cyst cyst formation. Now where the, the medical treatment, oh sorry, when the surgical treatment is not an option, either because the owner has decided against a surgery or because of financial constraints or if the patient, for example, is not stable enough or in critical condition, the medical therapy may be considered.
However, hormone therapy has had the valuable results over the years and mainly related to the to the type of cyst present because as we said, the cysts of the rava neoplastic cysts are likely to respond to this therapy because They are not supposed to be steroidogenic, whereas follicular cysts which are supposed to produce hormone may regress with a subsequent resolution of associated clinical signs. Now in terms of medical options available, percutaneous drainage of the disease is, it is possible, however, it does provide only temporary relief and the fluid usually reforms within the cyst in a few days to a couple of weeks, and generally it has to be followed by hormonal treatment. Human chorionic gonadotropin is being used as intramuscular injections, however, Treatment that has been associated with pain, allergic reactions, and reduced effectiveness.
Leroli acetate injections have also been reported to provide temporary improvement of symptoms, but no studies are being performed in guinea pigs. Gonadotropy releasing hormone injections have also been reported, where, GNH does not seem to stimulate a new reaction as a human coronic gonadotropin, and more recently the loreline acetate implant have been investigated as a prevention and treatment for. Cysts production in guinea pigs.
However, unlike other GNH agonists which are used to inhibit LH and FSH release, the slurin is used for its initial effect on the pituitary gland and associatedH surge. However, one study found that no reduction in ovarian size in guinea pigs with the use of this implant and actually according to another another study, the use of the slurry livingant to see, to, to induce the production of cysts in guinea pigs. Now guinea pigs have also been shown to have a unique form of GNRA compared to other mammals with different of the respective receptors where whether these features may affect the pharmacodynamic of a GNAH agonist such as a euprolide and the loin is currently not known.
Now, in terms of the surgery, I just wanted to point out that this procedure is actually quite challenging, challenging not just from an anaesthetic point of view, but challenging in terms of anatomic position of the ovaries in this species which are very far caudal into the abdomen with a very short ligament. The intestinal package is usually wrapped around the ovaries or in Immediate identification and isolation of the ovaries, especially when the large cysts present are present can be extremely, extremely complicated. aspiration of the fluid content can be reduced, obviously the volume of the system facilitates surgery, but definitely, this procedure is probably one of the most challenging ones in this in this species.
Now the last condition that I would like to take into consideration regards of respiratory issues and in particular bacterial infections so for which guinea pigs are very often presented. Now, Different microbial agents have been identified and have been recognised to potentially affect the respiratory tract of guinea pigs. The pathogenicity is extremely valuable because they can act either as primary or opportunistic pathogen, and some clinical infections are also very common as well as synergistic interaction in which combined infections can have an additive effect in producing severe respiratory.
Disease. Several predisposing factors have been identified and mainly are triggered by inappropriate husbandry and management, for example, lack of ventilation, damp and draughty housing conditions, inadequate housing, for example, overcrowding conditions, inappropriate environmental conditions such as inappropriate temperature, humidity, and ventilation, ammonia buildup which is A potent respiratory irritant, dietary changes, we've already discussed this in terms of other conditions as well. Inappropriate diet in terms of lack of vitamin C, for which guinea pigs have an absolute dietary requirement, and obviously the age because young, old, and pregnant, guinea pigs are more susceptible to develop infections.
Now clinic one signs that may be a non-specific, often guinea pigs are presented for weight loss, reduced appetite to anorexia, with poor condition or may have more evident respiratory signs such as ocular and or nasal discharge, sneezing, wheezing, gurgling sounds, or may Have that ro and posture in severe cases, obviously labour breathing to dysp may develop, and when the infection further extends to affect the inner ear, then neurological signs may also develop such as he or other neurological symptoms. Now the diagnosis may be challenging in terms of identification of the pathologic agent and is usually based on a combination of a physical examination and diagnostic tests. Deep nasal swabs for cultural insensitivity are definitely useful and will dictate the use of best antibiotics to use also in consideration of the potential toxicity.
That some of these antibiotics may have in guinea pigs. Conjunctive scrapings are extremely useful in this species for identification of ladophyla cavia, which may be responsible for conjunctivitis and associated respiratory signs in these species. Tracheallava has been totally reporting obviously the main difficulty in this species is the intubation because of the fusion of the base of the tongue with the soft palate which greatly restricts the opening and the of the mouth and the access to the blockies.
Culture and sensitivity, as we said, may be extremely important to direct the antibiotic treatment and avoid simply guessing what. Type of antibiotics to use. Radiography of the thorax and the skull are obviously extremely useful as well as other diagnostic modalities such as the CT or MRI which obviously provide even more detailed information.
However, in many cases, you know, the, the problem recurs and gross pathology may give just the definitive diagnosis. Now in terms of radiography, the interstitial pattern is probably the most commonly identified one, but this may be a some of other patterns and result in sorry, other patterns which result in a pulmonary or pacification. As you can see, the space occupied by the chest is very small as compared to the large abdomen, so it may be difficult in some cases to Actually interpret the chest of video graphs.
It's also important to remember that patient symmetry is extremely important because rotation, especially on DB or VD, can result in artifactual alteration in lung opacity and also the aspiratory status may mimic a disease, so definitely videography is important but may have its own challenges in when interpreting the images. Therapy. It's a combination obviously of oxygen when especially animals are presented with dyspnea, general supportive therapy including fluids, vitamin C, and assistive feeding.
Systemic antibiotics, obviously, these are extremely important, but Unfortunately, a gas is never useful in the sense that many different types of bacteria may be involved, so culture insensitivity wherever possible will simply, will definitely aid in the choice of the most appropriate treatment. Eucalytics and bronchodilators can be used orally or ne by nebulization and I'm not giving any And it dosages because these are widely available in the majority of the formularies available for exotic species and obviously consider the use of anti-inflammatories as an adjunct treatment and also to relieve, you know, the inflammation caused by, many of these infections. Nebilization is a useful adjunct to the systemic treatment to several drugs that can be added to the nebulizer, including antibiotics, and millitics, and bronchodilators, and mucrokinetics.
It, it is important to choose the appropriate nebulizer which delivers particle of appropriate size which are able to reach the lowest part of the respiratory tract. And finally, consider that outbreaks, especially in groups of rodents are often associated with environmental stressor. Therefore husbandly changes must be included in the therapeutic plan.
Thank you for your attention. So I'm very happy to take questions if there are any. Thank you very much for that, Elizabetta.
That was a fantastic, presentation and gave a really great insight into, say, some of those common conditions that you may be presented with, on a day to day basis. We do have a couple of questions that have come in throughout the presentation, but I would encourage anyone else to add some questions. Elizabeth is finished in good time, so we do have time to take a number of questions.
So please do get your thinking caps on and, please do type any questions you have into the Q&A box, and we'll ask them shortly. While I've got your attention, I would just like to draw your, eyes to, two upcoming expertise series we've got coming up. Lewis is going to kindly, put the links in our chat box on the side panel now.
The first is our mood series. Our mood series with Doctor Mike Scanlon is building on the success of the Mindfulness series and sleep series we've hosted in 2016 and 2017. The first live webinar with Mike is gonna be on the 20th of February and it's looking at how to identify your different moods and what coping mechanisms you can have to help deal with that.
And looking at the the theory of taming of the black dog. So as I say, if you enjoyed our mind from the series previously, then please do have a look at our mood series. The second expertise series we've got starting in February is, our diagnostic imaging.
This is a series of 4, webinars by, Professor Mike Kurtage from the University of Cambridge. Mike will be looking at thoracic cases, throughout, for the webinars and also looking at some new content as well. So once again, fantastic.
The Mod series is priced at £40 and the diagnostic images in place priced at 97. So please do have a look at those links that Lewis has put in the chat box. Also, before you leave the webinar tonight, the, you will see a survey pop up.
Please do complete the survey. It's great to get us all your feedback so we can help develop our programme of webinars for yourselves to enjoy. And it's also great for Elizabeth to get some feedback as well.
So, thank you very much for that. I've got a couple of questions here. So I'm with them.
Someone has asked Elizabeth, what is the best stroke, safest way to induce a guinea pig? I've only seen people gassing them down without any injectables. What's your views on that?
Well, consider that, unfortunately, there are no anaesthetics that are licenced in this species, so there are quite a few anecdotal reports of different protocols. It's difficult to tell you what's the best one because it is mainly personal choice. It depends on the clinical condition of the animal.
So many people will induce with or premedicate with a combination of an opioid and a benzodiazepine, for example, and then induce with a gas anaesthetic or a benzo sorry an opioid and gas induction. And so it really depends as well on, you know, how the animal is doing it and what procedure is going to be performed whether an analgesic needs to be included as well. On, in the protocol, so there are a lot of different ones that can be used.
I very rarely only induce with a gas anaesthetic, so I tend to, induce them with or premedicate with an opioids such as buprenorphine or biphanone depending on the procedure that is going to be performed and then for example, midazolam to reduce the stress as well and allow a better and less stressful induction of with the gas an aesthetic. Fantastic, thank you. And a few more questions coming through about anaesthesia, so I think you've covered them off quite nicely there.
Thank you. We've also got one from Greg. Greg asked, how do you treat dental absences in your abscesses, sorry, in your guinea pigs?
That, that would be probably on our presentation. But I think the, the first thing to do is to achieve a definitive diagnosis. You cannot treat an abscess without knowing from which tooth or teeth the abscess is rising because part of the treatment includes the removal of the affected or infected tooth or teeth.
So if that is not included in the abscess treatment, then the, you know, it's very likely. That the procedure will fail. So there are different techniques reporting.
My preferred one is marsupialization of the abscess, but again, abscess surgery is the tip of the iceberg, and there is a lot more that needs to be be done before and after the actual surgery for the abscess itself. Dental disease is very common, but it is very, very difficult, so this piece is probably one of the most difficult ones to diagnose and treat in terms of dental issues. Fantastic, thank you very much.
We've also got one over here, saying Angela saying I've been presented with guinea pigs which seem to have difficulty swallowing. In as much as they appear to have mouths stuffed with food, but not eating much at all, I've not been able to help much with these cases, you know, have you got any advice there for Angela? Yeah, that's probably one of the most common complications of dental disease in guinea pigs because as elongation of the clinical crowns or of the part of the tooth which is outside the gums occurs, the guinea pigs are not able to close their mouth and Therefore, are not able to swallow appropriately and this occurs to the point where the masticatory muscles are able to sort of keep their strength.
At that point, at some point then the, the strength of the masticatory muscles weakens, especially when it's only on one side. This is more evident because the mandible subloate on one side or the other. So what it is in.
Important in this case is to actually try and identify the dental disease because many of these cases will not be immediately evident because the elongation of the clinical crowns may be minimal, but it can affect these species much more than in other species. But I would say when they're not able to swallow, it's probably because they're not able to close the mouth properly and they're not able to to chew. Fantastic.
Thank you very much. We've got a question here about rates really. Obviously, you know, some of the things you were saying, in terms of the, you know, carrying out the diagnosis involves, you know, X-rays, bloods, surgery, etc.
. How much would you suggest you charge for a successful treatment of GDV in a guinea pig? You take in terms of money, yeah, well, I mean we are a referral centre so. So, probably more than in a first opinion practise and consider that to get to the surgery, you probably will have done quite a few things before.
So I would say for the old treatment, you can go from 500 to 1000 pounds and that's I, I know that is a very large estimate, but it really depends on what you're doing. If you're putting your catheters, for example, if you are starting to eat therapy, if you're using an infusion pump. If you are decompressing the stomach, if you then taking the animal to surgery, so it can be very expensive and you wouldn't believe how many people are actually prepared to do that and to pay them money.
It's quite incredible, but obviously people love their pets, so yes. What question you obviously you've flagged up about vitamin C a couple of times in your presentation. Are there any particular products that you would recommend?
There are many different ones out there. Yeah, there are many different ones out there, and I know now that, I'm not sure if it's supreme. There are the pellets with a new stable form of vitamin C, and there is better as well.
There are tablets, so there are, you know, many different ones out there, to be honest, many owners will have drops which I don't particularly like because it's very difficult to to calculate the exact amount, so I would prefer tablets then crushed and mixed with water or something like that. So you can just control the dosage a lot more clearly. No problem.
Just a couple more questions before we let you go off for the evening. We have one here. Saying they've seen guinea pigs with, excuse my pronunciation, podo dermatitis, to, and they struggle to control with antibiotics.
What would you recommend, we are doing a study about that, so, I'll probably be able to tell you a bit more in a few months. They've suggested maybe depriment. The brightment can be, yeah, can be very challenging.
I would say the first thing to do is the environment. Probably that is one of the most common reasons they get it as well is just inappropriate substrate and underlying diseases. They don't tend to exercise as much.
The identification of underlying diseases as well that may induce pain in the guinea pig reluctance to move. OK. And so you're saying that you're currently doing some research into that, where will you be the er er putting out the the results of the study, will that be available to the .
Yeah, it will be, but I, I still don't know. No problem. Well, we'll watch this space and hopefully we'll get that on a future webinar.
OK, thanks for that. And one last question. Saying, you know, well, it's a bit of an obs conversation so it's really interesting, but it's a shame that there's so many financial restrictions regarding treating, guinea pigs.
So, obviously, that's something that, you know, is that consideration. But as you say, you know, a lot of owners are prepared to pay that. And so obviously, it's just presenting with the facts and let them decide that.
But one last, question, I've seen a few, cheek teeth that look very fat. Almost like they've widened out. Do you know what this may be due to and how to approach the treatment?
Well, there is, there have been reports of macrodontsia in guinea pigs, so abnormally big teeth and the reason behind it, I don't know, they're not, not well known so far. There is only one report of those and I would say if the tooth is overgrown, it should be treated like any, any other, you know, corona. Elongation of of the cheek teeth and if it's causing any issue, obviously, it depends on what type of issues it's causing.
If it's infected, it could be removed, but it really depends on the, you know, on the single case, to be honest. No problem. 01 last one here, great talks, we, we have some great feedback for you tonight, Elizabeth, which is fantastic.
And the question is, what are your preferred prokinetics and how do you choose which one is most appropriate? It really is, is a challenging question because there isn't a lot out there. All the researches are based on lab animals and often not even live animals are just sections of intestines, so no, studies that have been performed in pet guinea pigs to say which is the most efficacious and where these, prokinetics work best.
So extrapolating from other species, I tend to use more of ranitidine. Which seemed to work on the upper and lower gastrointestinal tract and the see of pride when I need a more you know, focused action on the distal gastrointestinal tract. Fantastic, that's really useful.
Thank you very much for that. Well, I think that's all the questions covered off, so I'd like to thank my colleague Lewis, who's been supporting me tonight and making sure everyone has access. So thank you very much, Lewis.
And then I also thank you obviously to yourself, Elizabetta for that fantastic presentation. The presentation will be available to watch again on our website within the next 48 hours. And Elizabeth has also provided some multiple choice questions to go along with that so that you can test your knowledge and make sure you've taken on all that information.
So thank you for joining us, and we look forward to you, welcoming you on a webinar in the future. Thank you very much, everyone. Good night.