Patricia N. Olson

Estrous length, pregnancy rate, gestation and parturition lengths, litter size, and juvenile mortality in the domestic cat

Reproductive performance in a feline research colony of 14 queens is reported. Average estrous length in 38 cycles was 5.8 +/- 3.3 days, with a range of two to 19 days. Estrous length in 23 bred cycles was not shorter (p greater than 0.05) than in 15 nonbred cycles, suggesting that induction of ovulation does not decrease estrous length. Pregnancy rate in 23 bred cycles was 73.9%. Gestation length averaged 66.9 +/- 2.9 days with a range of 62 to 71 days (n = 15). Average parturition length was 16.1 +/- 14.3 hours (n = 7), with a range of four to 42 hours. Litter size ranged from one to five kittens, with an average of 3.7 kittens per litter (n = 15). Percent mortality by eight weeks of age was 29.1%, with 4.7% stillbirths.

Perspectives from man’s best friend: National Academy of Medicine’s Workshop on Comparative Oncology

Scientists gather to survey comparative oncology research and pinpoint potential contributions to human therapeutics. Scientists gather to survey comparative oncology research and pinpoint potential contributions to human therapeutics.

THE EFFECTS OF STAINS AND INVESTIGATORS ON ASSESSMENT OF MORPHOLOGY OF CANINE SPERMATOZOA

Percentage and types of morphological abnormalities found in canine spermatozoa were evaluated by three investigators using three stains (Giemsa-Wright stain [Diff-Quik], eosin Y/nigrosin [Hancock], and eosin B/nigrosin [Society for Theriogenology morphology stain] with conventional light microscopy, compared to phase contrast microscopy on unstained samples. The percentage of spermatozoa with abnormal heads, midpieces, and tails varied by technique and by investigator. Average percentages of morphologically normal spermatozoa were significantly higher in samples stained with Diff-Quik and samples examined by phase contrast microscopy than in samples stained with Hancock or Society for Theriogenology morphology stains. No effect of investigator on the percentage of morphologically normal spermatozoa was assessed. Results suggest that staining or preparation technique may alter the morphology of canine spermatozoa artifactually.

Ovarian and testicular function in the domestic cat: clinical management of spontaneous reproductive disease

Abstract Vaginal cornification and/or serum progesterone concentration may be used as indicators of follicular and luteal function in the cat in diagnosis of estrus, induced or spontaneous ovulation, ovarian remnant syndrome, and prolonged gestation. Feline sperm may be collected by electroejaculation, ejaculation into an artificial vagina, cystocentesis of the male following ejaculation or by vaginal wash of the bred female. Normal feline seminal plasma contains high concentrations of alkaline phosphatase, and may contain more than 10 000 colony forming units (CFU) ml−1 bacteria, most of which are normal preputial flora. Serum testosterone concentration, often undetectable (less than 0.02 ng ml−1) in the normal male, increases 1 h after gonadotropin-releasing hormone (GnRH) or 4 h after human chorionic gonadotropin (hCG) administration in the tom. Presence of penile spines is an indicator of testicular tissue or testosterone administration. Gonadectomy performed at 7 weeks or 7 months of age in male and female cats is associated with increased length of long bones due to delayed physeal closure, decreased heat production, and increased risk of obesity, and not with decrease in urethral diameter. Normal penile extrusion was not possible in 6 6 male cats neutered at 7 weeks of age or 2 5 male cats neutered at 7 months of age, owing to persistence of the balanopreputial fold, which normally undergoes dissolution under the influence of androgens.

The Golden Retriever Lifetime Study: establishing an observational cohort study with translational relevance for human health

The Golden Retriever Lifetime Study (GRLS) is the first prospective longitudinal study attempted in veterinary medicine to identify the major dietary, genetic and environmental risk factors for cancer and other important diseases in dogs. The GRLS is an observational study that will follow a cohort of 3000 purebred Golden Retrievers throughout their lives via annual online questionnaires from the dog owner and annual physical examinations and collection of biological samples by the primary care veterinarian. The field of comparative medicine investigating naturally occurring disorders in pets is specifically relevant to the many diseases that have a genetic basis for disease in both animals and humans, including cancer, blindness, metabolic and behavioural disorders and some neurodegenerative disorders. The opportunity for the GRLS to provide high-quality data for translational comparative medical initiatives in several disease categories is great. In particular, the opportunity to develop a lifetime dataset of lifestyle and activity, environmental exposure and diet history combined with simultaneous annual biological sample sets and detailed health outcomes will provide disease incidence data for this cohort of geographically dispersed dogs and associations with a wide variety of potential risk factors. The GRLS will provide a lifetime historical context, repeated biological sample sets and outcomes necessary to interrogate complex associations between genes and environmental influences and cancer.

Concurrent retrograde ejaculation and hypothyroidism in a dog: Case report

Retrograde ejaculation and hypothyroidism were diagnosed in a 19-mo-old Labrador retriever. The retrograde ejaculation was reversed following the administration of the sympathomimetic agent, pseudoephedrine hydrochloride, at a dose of 4 mg/kg per os given 1 and 3 h before semen collection. Antegrade ejaculation failed to occur after normalization of serum thyroid hormone levels by thyroxine supplementation. The pathophysiology of retrograde ejaculation is reviewed.

Terminating pregnancy in dogs and cats

Abstract The termination of canine and feline pregnancies might substantially reduce pet overpopulation in the United States. As many as four million pregnancies could be annually terminated to prevent the births of millions of puppies and kittens destined to be surrendered or abandoned. While ovariohysterectomy can be performed safely in most pregnant dogs and cats, the development and utilization of non-surgical abortifacients has been slow. Abortifacients which are highly effiacious, safe, and reasonably priced continue to be sought.