Midline Cysts of Colliculus Seminalis Causing Ejaculatory Problems in Stallions

Cystic structures are often seen during ultrasound examination of the internal genitalia of stallions. They are located between the ampullae of deferent ducts, either within the urogenital fold, or under the isthmus of the prostate (uterus masculinus). Occasionally, cystic dilatations are also found more caudally, behind the prostate, at the colliculus seminalis (urethral cyst, utriculus masculinus). These cysts are detected less frequently during routine examinations, possibly because of the fact that this area is screened less carefully for the pathologies than the more proximal portion of the internal reproductive tract of stallions. We have recently noticed that many stallions with ejaculatory problems have large cysts at the colliculus seminalis. This article describes the typical clinical presentation of these cases, diagnostic procedures, and management. In addition, we discuss the discrepancies in the currently used terminology pertinent to this condition, as well as introducing a new term, which seems to best describe the root cause of this disorder. Finally, this article presents new diagnostic and therapeutic options used in human medicine in similar cases, and proposes to investigate the applications of these methods in veterinary medicine.     

Effects of Topical Application of Misoprostol on Cervical Relaxation in Mares

Mares who have not delivered a foal early in life may experience limitations in cervical relaxation, primarily during oestrus. A closed cervix prevents intrauterine deposition of semen during natural breeding, may delay uterine clearance after insemination leading to intrauterine fluid accumulation in, and subsequent infertility. Therefore, a reliable pharmacological method of dilating the equine cervix would have practical application in veterinary medicine. The goal of this study was to investigate the effectiveness of topically applied, synthetic prostaglandin E₁ analogue (PGE₁) for stimulating dilation of the equine cervix. Ten mares in dioestrus were randomly assigned to one of two treatments in a single‐blind crossover study: (treatment) PGE₁ gel (1000 mcg compounded misoprostol cream) applied topically to the external cervical os (n = 5), and (control) a vehicle cream applied topically to the external cervical os (n = 5). Transrectal palpation and ultrasonographic measurements of the cervix were performed prior to, six and 24 h post‐treatment. Digital measurements were taken, per vagina, at six and 24 h post‐treatment. Mares were monitored through the subsequent oestrous cycle for ovulation. Mares were assigned to the opposite treatment group such that each mare served as her own control (crossover). Data were analysed using parametric (split‐plot anova ), as well as nonparametric (Kruskal–Wallis anova , Wilcoxon's rank‐sum test) methods. At six and 24 h there were no significant differences for tone, length, height, degree of relaxation or echotexture between control and PGE₁ treated groups at the measured time points (p > 0.05). Topical cervical application of PGE₁ did not induce a measurable degree of cervical relaxation under the conditions of this experiment.     

QUANTITATIVE MICRO-ESTIMATION OF ANTIBODIES IN THE SERA OF MAN AND OTHER ANIMALS

A micro-method is described by which as little as 10gamma of specific precipitate nitrogen may be determined with a fair degree of accuracy. The error in repeated determinations is about +/- 2gamma.     

Screening techniques for the evaluation of chemicals with activity as tick repellents

Screening techniques are described for the evaluation of the activity of tick repellents in vitro and in vivo, for the control of ticks of veterinary importance. In addition a modification of the in-vitro technique is described whereby the knockdown activity of chemicals may be assessed. There was a lack of correlation between results obtained in vitro and those obtained in vivo. Butopyranoxyl and N, N-diethyl-m-toluamide, which were highly active in vitro, showed only medium to low activity in vivo. Conversely, benzyl benzoate and dimethyl carbate, which were highly active in vivo, showed only low activity in vitro. Chemical breakdown, volatility, the ability of the chemical to bind to hair and skin, and differences in the behaviour and the morphology and physiology of the sense organs between larval and adult Rhipicephalus evertsi evertsi (Neumann 1897) are suggested as likely explanations for these differences in activity. Of the four synthetic pyrethroids tested, cypermethrin, deltamethrin, permethrin and fenvalerate, only the first three were shown to have good knockdown activity but only two, deltamethrin and permethrin, produced significant mortality of the exposed larvae. Further tests would be required to determine whether there is a correlation between knockdown and mortality.