Clinical management of the subfertile stud dog.

Many subfertile stud dogs can sire pups with appropriate management. Determination of the area of the problem (libido, ability to breed, semen quality) is the first step. Each of these areas can often be improved or managed. A complete history, physical examination, and semen evaluation should be performed on every patient. In specific cases, additional diagnostics may be helpful, including a CBC, biochemistry profile, urinalysis, semen cultures, ultrasonography, and biopsy. Management of breeding, including ovulation timing and intrauterine insemination, can be vital in dogs with low spermatozoal numbers or motility. Treatment of underlying prostatic disease can dramatically improve semen quality and fertility.

Clinical approach to infertility in the cycling bitch.

The majority of "infertile" bitches presented to the practitioner are victims of mismanagement. Careful evaluation of reproductive history, physical examination, and vaginal cytologic evaluation permit conception in these patients. Measurement of serum progesterone levels can help establish occurrence and timing of ovulation. Diagnosing true reproductive problems may require a minimum data base, guarded cultures, vaginoscopy, vaginography, ultrasound, and ultimately laparotomy for uterine biopsy and culture. The majority of these diagnostic procedures are readily available for the interested practitioner.

The effects of methyltestosteone on reproductive function in male greyhounds.

Oral administration of methyltestosterone (MT) at 50 mg/dog/day to intact adult male greyhounds for 90 d resulted in decreased (P < 0.05) mean daily sperm output and mean testicular length. Additionally, the mean diameter of seminiferous tubules in MT-treated dogs tended to decrease (P = 0.08). Mean concentrations of luteinizing hormone (LH) and follicle stimulating hormone (FSH) and concentrations of testosterone in serum were also decreased or tended to decrease (P = 0.0003 to 0.059) at various sampling periods during MT treatment, suggesting alterations in spermatogenesis resulted from decreased serum concentrations of gonadotropins and steroids. Mean daily sperm output, mean testicular length, mean seminiferous tubule diameter and mean concentrations of FSH in serum were not decreased (P > 0.05) at the end of a 90-d recovery period. However, mean concentrations of serum LH and concentrations of testosterone were still lower (P < 0.05) during five of six and one of six sampling times, respectively, during the recovery period than the pretreatment levels, suggesting a prolonged effect of MT treatment on the pituitary/gonadal axis.

Female pseudohermaphroditism in three sibling greyhounds.

Three 18-month-old Greyhound siblings were found to have female pseudohermaphroditism. The disorder in sexual differentiation likely developed because the dam received testosterone proprionate for estrus prevention. All 3 siblings had a prepuce (no penis), vagina, uterus, and ovaries.

Serum concentrations of thyroxine and 3,5,3'-triiodothyronine in dogs before and after administration of freshly reconstituted or previously frozen thyrotropin-releasing hormone.

Concentrations of serum thyroxine (T4) and 3,5,3'-triiodothyronine (T3) were determined after the administration of freshly reconstituted thyrotropin-releasing hormone (TRH), reconstituted TRH that had been previously frozen, or thyrotropin (TSH) to 10 mature dogs (6 Greyhounds and 4 mixed-breed dogs). Thyrotropin-releasing hormone (0.1 mg/kg) or TSH (5 U/dog) was administered IV; venous blood samples were collected before and 6 hours after administration of TRH or TSH. Concentrations of the T4 and T3 were similar (P greater than 0.05) in serum after administration of freshly reconstituted or previously frozen TRH, indicating that TRH can be frozen at -20 C for at least 1 week without a loss in potency. Concentrations of T4, but not T3, were higher after the administration of TSH than they were after the administration of TRH (P less than 0.01). Concentrations of T4 increased at least 3-fold in all 10 dogs given TSH, whereas a 3-fold increase occurred in 7 of 10 dogs given freshly reconstituted or previously frozen TRH. Concentrations of T4 did not double in 1 dog given freshly reconstituted TRH and in 1 dog given previously frozen TRH. Concentrations of T3 doubled in 5 of 10, 2 of 10, and 5 of 10 dogs given TSH, freshly reconstituted TRH, or previously frozen TRH, respectively. Results suggested that concentrations of serum T4 are higher 6 hours after the administration of TSH than after administration of TRH, using dosage regimens of 5 U of TSH/dog or 0.1 mg of TRH/kg.(ABSTRACT TRUNCATED AT 250 WORDS)