Urethral extension for correction of urovagina in cattle. A review of 14 cases

Chronic inflammatory and degenerative endometrial lesions in subfertile Criollo Limonero cattle; a B. taurus Latin-American breed threatened with extinction; A case-control study

Criollo Limonero is a tropical Bos taurus breed for sustainable dual purpose (milk and beef) production in the South-American tropics, which is currently threatened with extinction. The objective was to perform a clinical evaluation and histopathological assessment of uterine biopsy samples of repeat breeder (RB) Criollo Limonero cattle to determine the occurrence of pathological conditions as potential causes of subfertility. Twenty-four Criollo Limonero cattle [18 cows (5-13 years old) and 6 heifers (6-7.5 years old)] that had failed to conceive after four or more services were considered for this study. Additionally, five cows with history of adequate reproductive performance were used as a control group. Animals were submitted to physical exam, vaginoscopy, and ultrasonographical evaluation of the reproductive tract. Uterine biopsy samples were collected for histopathological evaluation. Vaginoscopy revealed that 41.7% of the RB cattle had abnormal vaginal secretions, while abnormal secretions were not observed in any control cow. Ultrasonographical examination of the uterus revealed the presence of free uterine fluid in 20.8% of the RB animals, while none of the control cows had fluid in the uterine lumen. In addition, ovarian cysts were observed in 25.0% of the RB animals. Histopathological evaluation of the endometrial biopsies revealed that mononuclear leukocyte infiltration, dilated uterine glands, and periglandular fibrosis were the most prevalent lesions in the sub-fertile animals. Chronic endometritis characterized by inflammatory (mononuclear leukocyte infiltration) and degenerative (dilated glands and periglandular fibrosis) endometrial lesions, and ovarian cysts were the most frequent reproductive pathologies observed in the studied subfertile Criollo Limonero cattle, suggesting a strong association with their reduced fertility.

Surgical Procedures of the Genital Organs of Cows

Reproductive surgical techniques are considered by practitioners/clinicians of theriogenology to be the most beneficial reproductive management that can be performed to treat conditions of cows that may affect fertility. Conditions affecting the reproductive tract can cause pathologic changes that may result in substantial economic and genetic losses to beef and dairy producers. Some injuries and diseases are amenable to surgical treatment. Surgical restoration of fertility preserves genetic potential and economic productivity. The surgical procedures described in this article are some of the most commonly used to restore fertility in cows with injury or diseases affecting their reproductive tracts.

Vaginal Microbiome Characterization of Nellore Cattle Using Metagenomic Analysis

Understanding of microbial communities inhabiting cattle vaginal tract may lead to a better comprehension of bovine physiology and reproductive health being of great economic interest. Up to date, studies involving cattle microbiota are focused on the gastrointestinal tract, and little is known about the vaginal microbiota. This study aimed to investigate the vaginal microbiome in Nellore cattle, heifers and cows, pregnant and non-pregnant, using a culture independent approach. The main bacterial phyla found were Firmicutes (~40–50%), Bacteroidetes (~15–25%) and Proteobacteria (~5–25%), in addition to ~10–20% of non-classified bacteria. 45–55% of the samples were represented by only ten OTUs: Aeribacillus, Bacteroides, Clostridium, Ruminococcus, Rikenella, Alistipes, Bacillus, Eubacterium, Prevotella and non-classified bacteria. Interestingly, microbiota from all 20 animals could be grouped according to the respiratory metabolism of the main OTUs found, creating three groups of vaginal microbiota in cattle. Archaeal samples were dominated by the Methanobrevibacter genus (Euryarchaeota, ~55–70%). Ascomycota was the main fungal phylum (~80–95%) and Mycosphaerella the most abundant genus (~70–85%). Hormonal influence was not clear, but a tendency for the reduction of bacterial and increase of archaeal populations in pregnant animals was observed. Eukaryotes did not vary significantly between pregnant and non-pregnant animals, but tended to be more abundant on cows than on heifers. The present work describes a great microbial variability in the vaginal community among the evaluated animals and groups (heifers and cows, pregnant and non-pregnant), which is significantly different from the findings previously reported using culture dependent methods, pointing out the need for further studies on this issue. The microbiome found also indicates that the vaginal colonization appears to be influenced by the gastrointestinal community.

Evaluation of a modification of the McKinnon technique to correct urine pooling in mares

The urethral fold of 30 mares was split transversely into dorsal and ventral shelves, and the ventral shelf was used to help create a urethral extension. The dorsal shelf was stretched caudally and sutured to the roof of the extension so that it covered at least the cranial half of the extension. For 20 mares, a relaxing, vaginal incision was created cranial to the external urethral orifice to enable the dorsal shelf to be retracted further caudally. Ten of the 30 mares (33.3 per cent) developed a defect, but none developed a defect in that portion covered by the dorsal shelf of the urethral fold. Two of the 30 mares (6.7 per cent) developed a defect so small that the defect could be detected only by inserting a dye, under pressure, into the tunnel. The total number of mares that developed only a grossly visible and palpable defect was eight of 30 (26.6 per cent). Four of the 10 mares that did not receive the relief incision and six of 20 mares that did receive the relief incision developed a defect in the extension. Modifying the McKinnon technique by transversely splitting the urethral fold and retracting the dorsal half helps prevent a defect from forming in the cranial portion of the extension. The dorsal shelf can be retracted further caudally by creating a relief incision on the floor of the vagina.

Prevalence of urovagina and its effects on reproductive performance in Holstein cows

Two hundred fifty-eight Holstein cows (n=344 lactations) from seven dairy herds were examined every month by vaginoscopy and transrectal palpation to determine the prevalence of urovagina, to investigate its effects on fertility, and to determine some risk factors for urovagina. Accumulation of urine in the vagina of a cow was diagnosed as urovagina and was classified into mild (urine only on the floor of vagina), moderate (urine covering less than or equal to half portion of the external cervical os), or severe (urine covering more than half or whole portion of the external cervical os). In total, 26.7% of lactations had urovagina (mild 11.3%, moderate 11.0%, and severe 4.4%). Survival analysis was used to derive the case definition of clinically relevant urovagina based on the factors associated with increased time to conception. Only moderate (hazard ratio [HR]=0.39) and severe (HR=0.20) degrees of urovagina were associated with reduction in pregnancy rate and thus defined as clinically relevant urovagina. Cows with clinically relevant urovagina had decreased AI submission rate (HR=0.52) and pregnancy rate (HR=0.35), required more inseminations per conception (5 vs. 2; P<0.001), had more days open (370 vs. 136; P<0.001), and were more likely not to get pregnant by 210 d postpartum (odds ratio [OR]=6.62) and to be culled for any reasons (OR=5.32) or for reproductive reasons (OR=9.54) compared with those in cows with no urovagina. Cows with clinically relevant urovagina had a higher risk of endometritis (36.4% vs. 9.2%; P<0.001) compared with that in cows without urovagina. Cow, low BCS at first postpartum examination (OR=2.85), endometritis within 60 d (OR=2.50), and horizontal vulva (OR=9.30) were risk factors for urovagina. In conclusion, 15.4% of lactations had clinically relevant urovagina that increased the risk of endometritis and had detrimental effects on fertility. Individual susceptibility, low BCS, and horizontal vulva increased the risk of diagnosing urovagina in Holstein cows.

Management of chronic vaginal prolapse in an eastern bongo (Tragelaphus eurycerus isaaci)

A 4.5-yr-old multiparous female eastern bongo (Tragelaphus eurycerus isaaci) presented with a prolapsed vagina 4 mo after dystocia and vaginal extraction of a large calf. The prolapse was corrected via manual reduction and vulvoplasty (Caslick operation). A melengesterol acetate contraceptive implant was placed and the bongo was asymptomatic for 6 yr until vaginal prolapse recurrence. The vaginal prolapse recurred four times over a 2-yr span and was managed with repeat Caslick procedures and several epidural injections using 95% grain alcohol. Complications secondary to long-term progestin implant usage, acquired urovagina, as well as perineal atony from the alcohol epidurals are believed to have contributed to prolapse recurrence. Ovariohysterectomy and vaginoplasty ultimately were elected and were curative. According to a survey conducted in response to this case, obstetrical issues and female reproductive tract problems appear to occur sporadically in captive bongo but are not uncommon.

Evaluation of a modified surgical technique to correct urine pooling in cows

Various surgical techniques to correct urovagina in cows describe creating a mucosal extension from the urethral orifice to the labia; however, a fistula often forms in the mucosal extension. The objective of the present study was to determine if the incidence of fistula formation could be decreased by covering transposed submucosal tissue on the dorsal aspect of the urethral extension with a mucosal graft. Cows in both the control group (19) and the experimental group (19) received a modified McKinnon technique of urethral extension; cows in the experimental group also had a sheet of mucosa, obtained from the dorsal aspect of the vestibule, grafted to submucosa exposed during creation of the urethral extension. During histological examination of the biopsy of the graft and its recipient site (harvested 1 week after surgery), neither inosculation nor revascularization of the graft was evident in any sample. Fourteen of 19 (74%) cows in the control group and 10 of 19 (53%) cows in the experimental group developed a fistula in the extension (P=0.18). We concluded that application of a mucosal graft to the subcutaneous tissue exposed to the vestibule using the McKinnon technique of creating a urethral extension was of little or no benefit in preventing the formation of a fistula in the extension. Furthermore, during evaluation of the extensions, digital palpation alone was often insufficient for detection of a fistula.

Factors associated with rectovaginal injuries in Holstein dairy cows in a herd in Tehran, Iran

Rectovaginal injuries can result in subsequent infertility in cows. In a retrospective study, records of 147 Holstein cows with evidence of rectovaginal injuries were reviewed to determine the odds ratio (OR) of these injuries and their related risk factors. The study was conducted in a large dairy (typical herd size 1420 cows) in Tehran between the years 1993 and 1996. Period prevalences were 0.4% fistula, 1.9% laceration (third degree), 5.7% pneumovagina, 1.5% urovagina and 0.8% mixed injuries. The highest risk occurred among first-calf heifers. Animals with dystocia, first-calf heifers and male calves were at higher risk for rectovaginal injuries. We concluded that (1) handling dystocia with care might have a substantial role in reducing rectovaginal injuries, (2) first-calf heifers are to be under close observation and care during calving, and (3) because rectovaginal injuries reoccur in the next calving, cows with the history of these injuries should be monitored at the next labor.

Urinary surgery

This article describes diagnosis, prognosis, pathophysiology, and methods to surgically correct abnormalities of the urinary system of ruminants. Surgery of the urinary system in ruminants most frequently is required to alleviate urethral obstruction or correct urinary bladder rupture. Several options for surgical management of those conditions are presented, but the prognosis for long-term survival or a return to reproductive function is poor if a urethrostomy is performed. Nephrectomy, translocation of ectopic ureters, removal of urachal remnants, and urethral extension to treat urovagina are performed less often in ruminants because animals requiring these procedures often are culled because of economic considerations or decreased productivity. Consequently, much of what has been described for ruminants is based on a limited number of cases or extrapolated from what has been learned from other species.