Uterine and fetal monitoring in the bitch.

The use of uterine and fetal monitoring improves the outcome of canine obstetrics. Much of the guesswork of managing whelping can be eliminated. At normal term, absolute indications for cesarean section are detected with monitoring, before multiple fetal deaths or any serious maternal compromise occurs. Bitches with previous history of cesarean section may be able to whelp vaginally successfully, having medical intervention based on monitoring. The anxiety level of owners during whelping is diminished, and the level of participation of the veterinarian improves.     

Uterine, cervical and vaginal microflora of the normal bitch throughout the reproductive cycle

Samples for microbiological culture were collected from the uterus of bitches using transcervical uterine cannulation (31 samples, 23 bitches) and from the uterus, cervix and vagina post mortem (19 bitches) at all stages of the reproductive cycle. Samples were cultured for aerobic and anaerobic bacteria and for aerobic mycoplasmas. Bacteria were always found in the uterus during prooestrus and oestrus (12 positive in 12 cultures) and rarely at other stages of the reproductive cycle: during anoestrus (one in 14) and other stages (none in 24). When microorganisms were detected at three sites post mortem, those found in the cervix and vagina were always of the same species as those found in the uterus. In six out of 13 instances, microorganisms were found in the cervix or vagina when none were found in the uterus. The mean number of isolates, number of bacteria seen in uterine cytology and bacterial growth were greater (P < 0–005) during oestrus and pro-oestrus than at other stages. Bacteria isolated from the uterus, in order of frequency, were Escherichia coli, Haemophilus species, α-haemo-lytic streptococci, Corynebacterium species, Streptococcus canis, Alcaligenes faecalis, Bac-teroides species, Pasteurella species and Proteus mirabilis. No mycoplasmas were cultured from the samples. This study indicates that the uterus of the normal bitch has a uterine microflora during pro-oestrus and oestrus that is similar to that of the vagina and cervix.     

Laparoscopic sterilization of the bitch and queen by uterine horn occlusion

Laparoscopic sterilization techniques, originally developed for use in women, were evaluated in the bitch and queen. In the first study (study I), the uterine horns of 6 bitches and 3 queens were occluded by electrocoagulation or plastic clips. The sites of occlusion were midway along the length of 1 cornus and at the uterotubal junction on the contralateral side. Both procedures effectively occluded the uterine horns, as evidenced by a distinctly visible separation of the reproductive tract. Laparoscopic examination 1 year after surgery revealed an enlarged, thin-walled, and fluid-filled uterine segment cranial to the midcornus occlusion sites in all animals. The contralateral horn was normal in appearance, except for the separation from the ovarian bursa. Three of the bitches developed pyometra (confined to the distended uterine segment) at 24 months, at 53 months, and at 72 months after sterilization, respectively. In a subsequent study (study II), 1 adult and 5 prepubertal bitches were sterilized by laparoscopic electrocoagulation of both uterine horns at the uterotubal junction adjacent to the ovarian bursa. Upon reexamination 1, 2, and 4 years later, the uterine horns of these females were normal in appearance, but were separated from the adjacent ovarian bursae. These females continued to be clinically healthy. Laparoscopic sterilization offers a rapid and safe alternative to ovariohysterectomy and, because of its minor invasive nature, can be performed on young, prepubertal animals. Such a procedure may have particular value as a simple, practical means of sterilizing dogs and cats on a mass basis.     

Transport of spermatozoa in the reproductive tract of the bitch: observations through uterine fistula

Using unilateral uterine fistulas, the time required for spermatozoa to reach the end of the fistula after natural mating, artificial insemination (AI) in a normal standing posture (NP), and AI standing on the head (SH) was investigated in each of three stages of estrus. Conceptivity in these bitches was also investigated. Five experimental bitches were tested during a total of 8 estrous periods. The results are as follows; the time required for spermatozoa to reach the end of the fistula was almost the same in the early and middle stages, i.e., 30 sec to 1 min after natural mating and SH and less than 2 min for half the bitches in NP, although no intrauterine transport could be observed in the other half. In most cases of mating during the late stage no spermatozoa were found after any of the 3 methods of insemination. Five animals became pregnant in these experiments, but the other three failed to conceive. The implantation of fertilized ova occurred also in the fistulated uterine horn in all cases of pregnancy.     

Application of vaginal cytology and plasma Srogesterone eterminations to the management of reproduction in the bitch

The use of vaginal cytology and plasma progesterone determinations in the management of 11 bitches presented to our small animal fertility clinic are described. Nine bitches were mated or artificially inseminated and seven became pregnant. Reproductive patterns detected included failure of ovulation, prolonged pro-oestrus with late ovulation, short pro-oestrus/oestrus with early ovulation, short pro-oestrus/oestrus with late ovulation and normal pro-oestrus/oestrus with late ovulation.     

Exfoliate vaginal cytology and plasma concentrations of progesterone, luteinising hormone and oestradiol-17sZ during oestrus in the bitch

Oestrus was characterised in nine German shepherd bitches by measuring plasma levels of luteinising hormone (LH), progesterone (P) and oestradiol-17ß (O). Hormone concentration data were compared with the eosinophilic index (EI) obtained from exfoliate vaginal cytology. Maximal values of O and LH occurred before the maximal EI value. The EI peak followed the O peak, with a two day delay. LH increased during the first 24 hours after the maximum 0 value, and P levels were then slightly higher than basal.     

Uterine torsion and uterine tear in a mare.

A 15-year-old Standard-bred mare was examined because of signs of abdominal discomfort in late gestation. Palpation per rectum revealed tight broad ligaments above and below the uterus, with the right broad ligament running across the top of the uterine body down toward the left, ventral side of the abdomen. A diagnosis of counterclockwise uterine torsion was made and surgical correction was approached via a left, flank laparotomy with the horse standing. The uterus was repositioned and a uterine tear encompassing 180 degrees of the uterine surface was found in the lateral, uterine body just cranial to the cervix. A live colt was delivered vaginally after uterine repositioning and the laparotomy incision was closed. The uterine tear was then repaired via a blind, vaginal approach. The mare was discharged 10 days after surgery. Repair per vaginum of a uterine tear is presented as an alternative treatment in cases for which the tear is recent, abdominal contamination is minimal, and the tear is easily accessible from the vaginal approach.     

Uterine drainage in the bitch for treatment of pyometra refractory to prostaglandin F2α

Uterine drainage was performed in three bitches with pyometra which had been treated unsuccessfully with PGF_2α. All of the bitches became clinically normal and one of them was mated and gave birth to live puppies. The mode of action of uterine drainage is discussed. Possible advantages of a combination of drainage and prostaglandin treatment are also considered.     

Uterine microbiology and antimicrobial susceptibility in isolated bacteria from mares with fertility problems

Uterine microbiology and antimicrobial susceptibility was investigated in 239 mares with fertility problems in a prospective study in Sweden. Uterine swab samples were collected with double guarded swabs and transported overnight before being cultured. The Minimum Inhibitory Concentrations (MIC) was determined for a panel of antimicrobials. From 152 of the 239 mares at least one bacterial species was isolated, most frequently E. coli (104 isolates), beta-haemolytic streptococci (31) and fungi (16). beta-haemolytic streptococci were more frequently (p < 0.01) associated with clinical endometritis than with repeat breeding. The opposite was true for E. coli (p < 0.01). Among beta-haemolytic streptococcal isolates some resistance was noted for 4 of 11 tested antibiotics, however, all isolates were susceptible to the widely used penicillin G. Among E. coli isolates enrofloxacin was the only of the 10 tested antibiotics for which no resistance was noted. Resistance was most commonly noted to cephalothin (39% of the isolates), streptomycin (22%), trimethoprim/sulphamethoxazole (15%) and ampicillin (11%). In conclusion, we show that both E.coli and beta-haemolytic streptococci are frequently associated with fertility problems in mares and that antimicrobial resistance is a common feature of E. coli but also recognised for beta-haemolytic streptococcal uterine isolates.     

Behavioral, ovarian and endocrine relationships in the pubertal bitch

Behavioral, ovarian and endocrine correlates were determined in seven bitches experiencing first estrus, and the results compared with previous data obtained on multiparous females. One or more atypical reproductive patterns were observed in certain bitches at the pubertal estrus. The ability of pubertal dogs to display normal reproductive relationships appeared to be related to age, because animals that exhibited normal sexual behavior and endocrine profiles tended to be older than females that produced aberrant patterns. For the latter group, atypical observations included lack of sexual receptivity and reduced or inconsistent patterns of circulating concentrations of estradiol-17 beta, luteinizing hormone (LH) or progesterone. Ovulation was confirmed in all four pubertal dogs subjected to laparoscopy, including two bitches that failed to demonstrate estrous behavior. In individual animals, it appeared that inadequate or sporadic elevations in titers of estradiol-17 beta during the preovulatory phase of the cycle were associated with reduced or abbreviated LH surge concentrations, and the latter were subsequently related to an absent or only minor preovulatory rise in serum progesterone. Reduced preovulatory estradiol-17 beta concentrations and a delayed increase in circulating progesterone were also associated with a lack of sexual receptivity. These results (1) suggest that hormonal insufficiencies or irregularities exist in certain bitches at the pubertal estrus and that such atypical activity appears more characteristic of the first than later adult estrous periods, and (2) are consistent with the theory that estrogen preconditioning and a decrease in the endogenous estrogen to progesterone ratio are important in the initiation of sexual receptivity in this species.     

Vaginal hyperplasia in the bitch: Literature review and commentary

We reviewed the incidence, etiology, clinical presentations, diagnosis, treatments and prevention of canine vaginal hyperplasia, and describe a simple surgical technique for its correction as practiced at the Small Animal Clinic, State University of Utrecht, The Netherlands. Many different treatments have been used, and some are novel approaches. In many cases, prevention is accomplished if the bitch is ovariectomized; there is a high incidence of recurrence with medical treatment.     

Otic cytology in health and disease.

Accurate characterization of the primary cause and perpetuating factors is essential for successful management of ear disease in dogs and cats. Cytology is a simple, rapid, and practical diagnostic test that should be performed routinely on any and all patients presented for clinical signs consistent with otitis externa. In combination with clinical signs, otoscopic evaluation, and diagnostic testing of primary disease, serial cytology enhances the ability of veterinarians to diagnose secondary infections, monitor progression of disease, evaluate response to therapy, and make appropriate management decisions. Cytologic specimens should be evaluated for the presence, numbers, and characteristics of three key features: yeast, bacteria, and leukocytes. More than five yeast organisms or more than 25 bacteria per high-powered field is suggestive of significant microbial activity warranting therapeutic intervention. The presence of leukocytes, particularly with phagocytized bacteria, indicates "true infection" rather than overgrowth; if suppurative discharge is present, systemic therapy is needed. Cytology combined with culture and susceptibility is the best method for identification of bacterial overgrowth and infection; however, if only one test can be performed, always choose cytology. Culture results assist in the selection of appropriate antibiotic therapy, but cytology determines whether systemic antibiotics are indicated, which organisms are most significant, and when therapy can be discontinued.     

Megestrol acetate for estrus postponement in the bitch.

Megestrol acetate was given orally to 389 bitches in early proestrus, at a dosage of 2.2 mg/kg (1 mg/lb) per day for 8 days. Estrus was suppressed in 357 (92%) of the bitches. Additionally, 119 bitches in anestrus were given the drug at the rate of 0.55 mg/kg (0.25 mg/lb) per day for 32 days. Estrus was suppressed in 115 (98%) of these bitches. Adverse effects were minimal. Pyometra developed in 3 (0.8%) of the 389 bitches treated in early proestrus. The drug also was given to 19 bitches at the rate of 0.55 mg/kg/day for 32 days, regardless of the stage ofting at the 1st posttreatment estrus and 4 after mating at the 2nd posttreatment estrus. Litter size, success in rearing pups, and sex ratios were not significantly different from these factors in 53 litters from untreated bitches.     

Prostaglandin therapeutics in the bitch and queen

The use of prostaglandin F2 alpha as an abortifacient and for the treatment of certain diseases affecting the reproductive system of the bitch and queen is reviewed. Doses of 0.5 to 1.0 mg/kg PGF administered by intramuscular or subcutaneous injection at intervals of 24 or 48 h after mid-gestation appears to be a satisfactory luteolytic-- abortifacient regime for use in dogs and cats. Doses of 0.25 to 0.5 mg/kg in the bitch and 0.5 to 1.0 mg/kg PGF in the queen, at intervals of 24 or 48 h, may be used as an adjunct to the therapy of metritis, endometritis or pyometritis. A median lethal dose of 5.13 mg/kg has been derived for use of PGF in the bitch and this is thought to be similar for use of PGF in the queen. Side effects of defecation and/or vomition may be observed in the bitch and queen using routine therapeutic doses.     

Induction of estrus and ovulation in the bitch, using exogenous gonadotropins

The capability of pregnant mare serum (PMS) and human chorionic gonadotropin (HCG) to induce estrus and ovulation was tested in mature, anestrous bitches. The PMS was given for 10 consecutive days in 1 of 3 regimens: 500 IU/day (experiment 1), 250 IU/day (experiment 2), or 20 IU/kg/day (experiment 3). The HCG was given as a single 500-IU dose on experimental day 10. Controls were given saline solution. Vaginal smears were collected on days 1, 3, 5, 7, 9, and 12 by jugular venipuncture, and the plasma was assayed for progesterone concentration by radioimmunoassay. On day 13, the bitches were euthanatized, ova were flushed from the uterine tubes (oviducts), and the ovaries were collected and prepared for microscopic examination. Fourteen of 25 bitches treated with PMS and HCG showed estrus and ovulated. Proestrus (vaginal bleeding) commenced between experimental days 7 and 10. Estrus commenced on day 9 or 10. Progesterone increased from approximately 1 ng/ml on day 1 to more than 6 ng/ml on day 12. Numbers of ovulation sites on both ovaries were 4.7 +/- 1.1 and 4.6 +/- 0.5 (mean +/- SEM) in those given the daily doses of 500 and 250 IU of PMS and 9.8 +/- 1.5 in experiment 3 bitches. Eleven hormone-treated dogs and 7 saline-treated dogs did not show any detectable response. Neither cystic nor unovulated, luteinized follicles appeared on the ovaries.