Leptospira interrogans serovar hardjo is not a major cause of bovine abortion in Victoria

The aim of this study was to determine whether evidence could be obtained of foetal infection with Leptospira interrogans serovar hardjo in aborted foetuses collected from dairy farms. Material from 197 abortions occurring over a wide area of Victoria was collected over 3 years. None of 195 foetal kidney cultures or 7 cultures from membranes was positive for leptospiral organisms. Immunogold silver staining for leptospires was performed on sections of kidneys, lungs or heart from 156 foetuses, with negative results. Evidence of transient leptospiral infection in 11 of 123 foetuses was obtained by foetal heart blood serology. Two isolates of L. interrogans serovar hardjo were obtained from the urine of milking cows. These strains were examined by restriction endonuclease analysis and both were shown to be of the genotype Hardjobovis, as have been all Australian isolates studied so far. It appears that foetal infection with serovar hardjo is not associated with any substantial proportion of bovine abortions in Victoria, in contrast to the situation in Northern Ireland. The apparent absence from Victoria of the pathogenic genotype Hardjoprajitno is a possible explanation.     

Cerebral and conjunctival haemorrhages associated with von Willebrand factor deficiency and canine angiostrongylosis

A case of angiostrongylosis is described in a 14-month-old golden retriever bitch. Conjunctival haemorrhage and neurological signs, referable to a space-occupying cerebral lesion, were associated with defective primary haemostasis caused by low levels of von Willebrand factor. Full clinical recovery followed treatment with desmopressin, fresh whole blood transfusion, fenbendazole and supportive care. The magnetic resonance image of the suspected organising haematoma is described. Similarities to the human condition, acquired von Willebrand syndrome, and a possible role for aberrant larval migration in haematoma formation are suggested.     

Corticosterone- and aldosterone-secreting adrenocortical tumor in a dog

A dog was evaluated for clinical signs suggestive of hypercortisolemia. Serum biochemical testing revealed hypernatremia and hypokalemia. Serum cortisol concentration after injection of ACTH was less than the lower reference limit. An adrenal gland tumor was visualized via ultrasonography and computed tomography. Histologic examination confirmed that the mass was an adrenocortical carcinoma. Excess adrenal secretion of corticosterone was hypothesized to be the cause of the signs of glucocorticoid excess. Serum corticosterone secretion was high before and after ACTH injection, compared with clinically normal dogs and dogs with hypercortisolemia and classic hyperadrenocorticism. Hyperaldosteronemia was detected as well. Treatment with mitotane was instituted and successful for a period of 4-months until the dog was euthanatized for neurologic problems that were most likely unrelated to endocrine disease.     

Ahmed valve implantation to control intractable glaucoma after phacoemulsification and intraocular lens implantation in a dog

An 11-year-old spayed female Miniature Poodle presented with bilateral senile cataracts. Treatment was cataract removal by phacoemulsification and intraocular lens implantation. Five hours after surgery the operated right eye was partially closed and painful. The right pupil was fully dilated, there was generalized corneal edema, and intraocular pressure (IOP) was increased. After 12 h of medication IOP was controlled. Ten weeks after surgery the owners reported cloudiness of right eye, and the dog was again evaluated. The IOP was again increased and an Ahmed valve was implanted. This case describes describe the progression of this case and benefits of controlling postcataract surgery glaucoma by the implantation of an Ahmed valve.     

Ovarian Responses, Hormonal Profiles and Embryo Yields in Anoestrous Ewes Superovulated with Folltropin®-V after Pretreatment with Medroxyprogesterone Acetate-releasing Vaginal Sponges and a Single Dose of Oestradiol-17β

In ruminants, superovulatory treatments started at the time of follicular wave emergence result in greater and less variable ovulatory responses and embryo yields compared with the treatments begun in the presence of a large growing antral follicle(s) from the previous waves. The progesterone–oestradiol treatment is routinely used for follicular wave synchronization in cattle. The main objective of this study was to characterize the ovarian responses, hormonal profiles and in vivo embryo production in anoestrous Rideau Arcott ewes (May‐June), which were superovulated after pretreatment with medroxyprogesterone acetate (MAP)‐releasing intravaginal sponges and a single dose of oestradiol‐17β (E₂‐17β). Six days after insertion of MAP sponges, eight ewes were given an i.m. injection of 350 μg of E₂‐17β (E₂‐17β‐treated ewes); 10 ewes were given an i.m. injection of vehicle (control ewes). Multiple‐dose Folltropin®‐V treatment, followed by the bolus injection of GnRH (50 μg i.m.), began 6 days after E₂‐17β/vehicle injection. Transrectal ovarian ultrasonography revealed that: (i) the interval between E₂‐17β/vehicle injection and regression of all follicles ≥5 to 3 mm in diameter was shorter (p < 0.01; 2.6 ± 0.4 vs 4.8 ± 0.6 days respectively); and (ii) the interval between injection and emergence of the next follicular wave was longer (p < 0.05; 5.4 ± 0.3 vs 1.2 ± 0.4 days, respectively) in E₂‐17β‐treated than in control ewes. During the 6 days after injection, the mean FSH peak concentration and basal FSH concentration were lower (p < 0.01) in E₂‐17β‐treated ewes. The mean ovulation rate and the number of recovered embryos did not differ (p > 0.05) between the two groups of ewes. However, the number of luteinized unovulated follicles per ewe, and the variability in the number of luteal structures and overall embryo yield were less (p < 0.05) in E₂‐17β‐treated compared with control ewes. In conclusion, the MAP–E₂‐17β pretreatment significantly reduced the variability in ovarian responses and embryo yields, without affecting the embryo production in superovulated anoestrous ewes.