Johnston Sd

Prostatic disorders in the dog

Common canine prostatic disorders include benign prostatic hypertrophy (BPH), prostatitis, prostatic cysts and prostatic adenocarcinoma. BPH is a spontaneous and age-related disorder of intact male dogs, which occurs in more than 80% male dogs over 5 years of age, and which is associated with clinical signs of sanguinous prostatic fluid, constipation and dysuria. BPH signs respond to castration or to finasteride treatment (0.1-0.5 mg/kg per os once daily), as finasteride inhibits conversion of testosterone to dihydrotestosterone, causing prostatic involution via apoptosis. BPH often occurs concurrently with prostatic infection, abscessation, cysts and neoplasia in the intact dog, and finasteride-induced prostatic involution may be beneficial in treatment of all of these conditions except neoplasia. Two studies suggest that risk of prostatic adenocarcinoma is increased in neutered, compared to intact male dogs. Although canine prostatic neoplasia, unlike human prostatic neoplasia, usually does not respond to androgen deprivation, recent reports of prostatic intraepithelial neoplasia (PIN) in a high percentage of older male dogs, with and without prostatic adenocarcinoma, suggests that PIN may be a precursor to adenocarcinoma in the dog as it is believed to be in man.

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.

Cadmium effects on bone metabolism: Accelerated resorption in ovariectomized, aged beagles

The purpose of this study was to evaluate, in an animal whose skeleton is comparable to humans, the combined effects of estrogen depletion and Cd exposure on bone resorption by monitoring skeletal release of 45Ca and to determine whether Cd-induced bone resorption occurred independent of osteotropic hormone changes and renal dysfunction. Cd exposure following ovariectomy or sham surgery was for 7 months: 1 month by oral ingestion of capsules (1, 5, 15, 50 ppm) and 6 months via drinking water (15 ppm). Serum and fecal 45Ca were increased at 1 week following ovariectomy (OV) (54 +/- 9% and 122 +/- 40%, respectively), but this response was attenuated by 2 weeks. Five of seven exposed dogs had increased serum and fecal 45Ca during the 50-ppm Cd capsule period (15-40% and 15-190%, respectively). Serum 45Ca levels in OV/+Cd dogs showed a significant and consistent increase within 1 week of initiating each of three separate Cd.H2O exposure cycles. Blood Cd levels increased over time from 2 to 15 micrograms/l, coinciding with the elevated serum 45Ca concentrations. No correlation was observed between serum 45Ca increases and parathyroid hormone, 1,25-(OH)2-vitamin D, or calcitonin. No effects of ovariectomy and/or Cd were observed in total serum Ca, calciotropic hormone concentrations, serum or urinary phosphorus and creatinine, creatinine clearance, or urinary specific gravity. Urinary Cd concentrations ranged from 7 to 50 micrograms/l in exposed dogs but were not detectable in nonexposed dogs. Urinary protein concentrations showed no differences between groups. Cd increased bone resorption (skeletal 45Ca release) in ovariectomized and sham-operated dogs without renal dysfunction or calciotropic hormone interaction. Based on our results, Cd is an exogenous factor which exacerbates bone mineral loss in postmenopausal osteoporosis.

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.

Effects of chemotherapy and remission on carbohydrate metabolism in dogs with lymphoma

After a 12‐hour fast, blood samples were obtained from 27 dogs with previously untreated lymphoma before and 5, 15, 30, 45, and 60 minutes after an intravenous (IV) challenge with 500 mg/kg dextrose. This procedure was done for each dog before up to five treatments with the IV doxorubicin (30 mg/m2 every 3 weeks). All dogs achieved a complete remission. Samples were assayed for glucose, lactate, and insulin concentrations, and results were compared statistically with those from 16 normal control dogs of similar weight and age undergoing an identical dextrose challenge before and 3 weeks after receiving one dose of IV doxorubicin (30 mg/m2). Glucose, lactate, and insulin concentrations did not change significantly in response to glucose challenge in control dogs after doxorubicin chemotherapy. Lactate and insulin concentrations in untreated dogs with lymphoma were significantly higher than controls. This hyperlactatemia and hyperinsulinemia did not improve when dogs with lymphoma were put into remission with doxorubicin chemotherapy. The results indicate that carbohydrate metabolism is altered in dogs with lymphoma, and that these abnormalities do not improve when a complete remission is obtained with doxorubicin chemotherapy.

Etiopathogenesis, Clinical Manifestations, and Management of Canine Calcium Oxalate Urolithiasis

Calcium oxalate uroliths are commonly called metabolic uroliths because they are sequelae of a variety of metabolic abnormalities that alter the composition of body fluids and urine. Factors incriminated in the etiopathogenesis of calcium oxalate urolithiasis include hypercalciuria, hyperoxaluria, and hyperuricosuria. The predominant type of calcium oxalate urolith encountered in dogs is the monohydrate form; however, the dihydrate form may also occur. Male dogs have been more frequently affected than female dogs. Medical therapy should be formulated with the goal of reducing urine concentration of calculogenic substances.

Evaluation of the ICAGEN-Target canine ovulation timing diagnostic test in detecting canine plasma progesterone concentrations.

Accuracy of the ICAGEN-Targeta progesterone enzyme-linked immunosorbent assay (ELISA) test kit to measure plasma progesterone was compared to that of radioimmunoassay (RIA) in 166 canine samples. Overall agreement of ICAGEN-Target ELISA and RIA was 85% (141/166). Agreement of ELISA and RIA at high (5 ng/ml or greater), medium (greater than 1 ng/ml, less than 5 ng/ml), and low (0 to 1 ng/ml) plasma progesterone concentrations was 96% (72/75), 73% (19/26), and 77% (50/65), respectively. Use of whole blood resulted in unreliable progesterone concentration results by ELISA when compared to plasma progesterone concentrations measured by RIA (n = 140). Use of this ELISA test kit to determine canine ovulation date should start within three to four days after onset of proestrus and continue every other day until the first detection of medium concentrations (greater than 1 ng/ml, less than 5 ng/ml). Daily plasma testing during the time of transition from medium to high (5 ng/ml or greater) concentrations was essential for determining ovulation date. The second or third day after the first appearance of high plasma progesterone concentrations using this kit should be the day of breeding for optimal reproductive performance.

X trisomy in an Airedale bitch with ovarian dysplasia and primary anestrus

A 79,XXX chromosome complement was detected in a four-year-old Airedale Terrier bitch examined for primary anestrus. Serum concentrations of luteinizing hormone (LH) and follicle stimulating hormone (FSH) were markedly elevated. Ovaries contained solid epithelial cords and large masses of interstitial cells but lacked follicles and corpora lutea. Somatic abnormalities were not observed. X trisomy is reviewed in six species in which it has been described.

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.