Ovarian cysts in the guinea pig (Cavia porcellus)

Updates on Cystic Ovarian Disease in Guinea Pigs

Cystic ovarian disease is the most common reproductive tract disorder in female guinea pigs, and concurrent uterine pathology may also be present. Nonspecific clinical signs include decreased appetite, lethargy, hunched posture, weight gain, palpable mass(es) in the midabdomen, and progressive abdominal distension. Additionally, bilateral, nonpruritic alopecia of the flank and ventral abdomen; hyperkeratosis, crusting, and/or hyperpigmentation of nipples; clitoral hypertrophy; reduced fertility; and behavioral changes may also be appreciated. Confirmation of disease is most often made with abdominal ultrasound but may also occur during exploratory abdominal surgery. Recommended treatment is surgical management with ovariohysterectomy or ovariectomy.

Mammary and reproductive tract tumours and tumour-like lesions of 286 small pet mammals: a retrospective study

Small mammals are very popular companion animals, and the incidence of particular tumour types in these animals is the subject of extensive research. We carried out a retrospective and comparative analysis of the incidence of reproductive tract and mammary tumours and tumour-like lesions collected from 103 pet rabbits, 75 pet rats, 71 guinea pigs, 12 mice, 11 hamsters, eight African pygmy hedgehogs, four ferrets and two chinchillas. The results indicate that uterine tumours and tumour-like lesions are common in pet rabbits, guinea pigs and African pygmy hedgehogs. In pet rabbits, the most common uterine tumour was endometrial adenocarcinoma, while in guinea pigs benign lesions predominated (ie, leiomyoma, endometrial adenoma, cystic endometrial hyperplasia and deciduoma). Uterine tumours in African pygmy hedgehogs included adenosarcomas and endometrial polyps. Ovarian lesions were found only in guinea pigs (ovarian rete adenomas, rete cysts) and African pygmy hedgehogs (mostly granulosa cell tumours), while testicular tumours were diagnosed in pet rabbits, one pet rat and one guinea pig. Mammary tumours were common in pet rabbits, pet rats, guinea pigs, mice, hamsters and African pygmy hedgehogs. In pet rats, the most common mammary tumour was fibroadenoma, while in other animals carcinomas predominated. In guinea pigs and, to a lesser extent, in pet rats, a significant percentage of mammary tumours occurred in males. Guinea pigs seem to be predisposed to mammary tumours of ductal origin. This study describes for the first time uterine angioleiomyoma in the pet rabbit and mammary spindle cell carcinoma in the Djungarian hamster and chinchilla.

Rodent Pediatrics

This article reviews the development, hand-rearing, feeding, housing, and social behavior of common pet rodent species (rats, mice, hamsters, gerbils, guinea pigs, chinchillas, and degus). In addition, common gastrointestinal, respiratory, cardiovascular, dermatologic, musculoskeletal, neurologic, and ophthalmic disorders in pediatric pet rodents are reviewed. Preventative care and indications for spaying and neutering are discussed.

Rodent Dermatology

This article reviews the most common dermatologic conditions of the pet rodent population, including the prevalence, clinical signs, diagnosis, and treatment recommendations.

Problem-Oriented Approach in Exotic Companion Mammals

Dermatologic disorders are some of the most common conditions affecting exotic companion mammals. This article provides a clinical approach of the conditions presenting with alopecia, pruritus, scaling/crusting, erosion/ulceration, and nodules in order to select and interpret the appropriate diagnostic tests to achieve a diagnosis for a successful treatment.

Mast cells and Kurloff cells - Their detection throughout the oestrous cycle in normal guinea pig ovaries and in guinea pigs with cystic rete ovarii

Mast cells (MCs) and Kurloff cells (KCs) were detected in guinea pig ovaries in the follicular and luteal phases of the oestrous cycle. The samples of ovaries were fixed in Mota's basic lead acetate. Toluidine blue was used for detection of MCs and periodic acid-Schiff for detection of KCs. The percentage of KCs in a differential leukocyte count was determined in blood smears stained according to the Pappenheim method. Non-pregnant females with normal ovaries and with cystic rete ovarii were included in the study and the numbers of MCs and KCs were compared in these two groups and in follicular and luteal phases of the oestrous cycle. MCs' distribution in ovaries was different in the guinea pig in comparison to previously studied species: MCs were found exclusively in the superficial layers of cortical stroma and no significant difference was found between the number of MCs in the follicular and luteal phases, neither in normal ovaries, nor in ovaries with cystic rete ovarii. Significantly lower numbers of MCs were found in ovaries with cystic rete ovarii (P < 0.01) in contrast to normal ovaries. A significantly higher percentage of KCs in the peripheral blood was found in the follicular phase (P < 0.05), whereas no significant difference was found in relation to the presence of cystic rete ovarii. Interestingly, no KCs were found in the samples of ovaries (either in the follicular or luteal phase, and with or without cysts). Thus, the expected role of KCs in ovarian physiology or in the aetiology of the cystic rete ovarii can be excluded.

Geriatric Care of Rabbits, Guinea Pigs, and Chinchillas

Specialized veterinary care needed for geriatric rabbits, guinea pigs, and chinchillas is described along with medical conditions common in this age group. Clinical signs of pain, safe analgesics, therapeutics, and alternative modalities are outlined along with guidelines for end-of-life care and decision-making. A handout containing advice for small mammal herbivore clients with geriatric pets is included.

Laparoscopic ovariectomy in guinea pigs: A pilot study

OBJECTIVE

To assess the feasibility and safety of laparoscopic ovariectomy in guinea pigs utilizing 3-mm minilaparoscopic instruments.

STUDY DESIGN

Experimental pilot study.

ANIMALS

Guinea pigs (n = 3).

METHODS

The guinea pigs were sedated, placed under general anesthesia, and intubated under endoscopic visualization. A 3-port technique was used with a 3.9-mm cannula for the endoscope and two 3.5-mm cannulas accommodating 3-mm endoscopic instruments including a 3-mm vessel sealing device, grasping forceps, and endoscopic scissors. The abdomen was insufflated with CO₂ to a pressure of 6-8 mm Hg. The guinea pigs were manually tilted 90° laterally to visualize the dorsally positioned ovaries.

RESULTS

The procedure was successfully performed in all 3 animals. The surgery times were 120, 45, 45 minutes for the 3 guinea pigs, and anesthesia times were 186, 90, and 76 minutes, respectively. Placing the animals in complete lateral recumbency was found to be critical to visualize and manipulate the ovaries. The guinea pigs recovered smoothly from anesthesia.

CONCLUSION

Laparoscopic ovariectomy with 3-mm minilaparoscopic instrumentation using a 3-port technique was feasible in guinea pigs.

CLINICAL SIGNIFICANCE

Laparoscopic ovariectomy can be considered as an alternative to open ovariectomy as an elective surgical technique to prevent reproductive disorders in guinea pigs.

Ovarian lesions in 44 rabbits (Oryctolagus cuniculus)

The clinical and pathological records of 44 domestic, female rabbits with an age ranging from 6-124 months (median age: 63.5 month) were assessed retrospectively for ovarian lesions. Included were all rabbits that underwent an ovariohysterectomy with a subsequent pathological examination of the genital tract between March 1997 and June 2016. Pathological examination revealed ovarian lesions in 12 of the 44 rabbits including follicular cysts (n=7), cystic rete ovarii (n=3), widespread ovarian necrosis with dystrophic calcification (n=2), ovarian adenoma (n=1). Clinical examination including radiographs only suggested ovarian disorders in two cases of ovarian necrosis with dystrophic calcification and in two cases of cystic rete ovarii. Clinical significance was only conclusive in a case of cystic rete ovarii.

Reproductive Disorders in Pet Rodents

Reproduction diseases are common presentations in small rodents. Some can be presented to the clinician as an emergency where a fast and effective treatment is required. This article presents an overview of reproductive disorders in these species. Diseases affecting the ovary, uterus, testicles, and mammary gland are developed in rats, mice, hamsters, and gerbils: inflammatory, infectious, and neoplasia. Clinical signs, diagnosis, and treatment information are included. Some specific indications about the surgical reproduction procedures are described. Literature regarding reproductive disorders exists for squirrels and prairie dogs. Brief information about the normal anatomy of the reproductive system is given.

Reproductive Medicine in Guinea Pigs, Chinchillas and Degus

Guinea pigs, chinchillas, and degus are hystricomorph rodents originating from South America. They are commonly presented as exotic pets in veterinary practice. Reviewing the anatomy and physiology of their reproductive tract helps to offer better client education about preventive medicine and helps to act faster in emergency situations. Choosing the right anesthetic protocol helps to prevent complications. This article should aid as a guideline on the most common reproductive problems of these 3 species and help in making decisions regarding the best treatment options.