Thermotaxis that sperm migrate to higher temperature area has been confirmed in rabbit and human. In this study, we examined the migration ability of bull sperm in a temperature gradient to confirm thermotaxis and elucidate the involvement of calcium in such thermotaxis, as well as the relation between sperm capacitation and bull fertility. Thermotaxis was evaluated in a temperature gradient of...

Bull trout (Salvelinus confluentus) were recently listed as threatened in the United States under the federal Endangered Species Act. Present and historical habitat of this species includes waterways that have been impacted by metals released from mining and mineral processing activities. We conducted paired bioassays with bull trout and rainbow trout (Oncorhynchus mykiss) to examine the relati...

This study evaluated night and day semen collection regimes in Holstein and Brahman bulls (four bulls of each breed) that were collected weekly, each during a morning and a night collection. Ejaculates (n=64) were obtained via artificial vagina over 4 weeks. The first collection of each week alternated between night and day. Two collection teams were employed. Bull behavior parameters included ...

OBJECTIVE To determine prevalence of infection with tritrichomonas fetus in a bull population; assess influence of age, breed, and grouping; assess effects on measures of cow performance (pregnancy rate, weaning percentage, weaning weight); and estimate test sensitivity. DESIGN Epidemiologic study. ANIMALS 1,383 bulls and records for 28,471 cows bred by these bulls in the immediate past bre...

Clusterin is a major protein in bull reproductive tract secretions and sperm membrane extract. A polyclonal antibody was produced against clusterin from bull cauda epididymal fluid (CEF) and used for the localization of the protein on bull spermatozoa. Immunoblotting of unreduced bovine samples showed that the anticlusterin antibody reacted with a protein of approximately 94- to 100-kd in rete ...

Bull-horn wounds are well known in Spain, many Latin-American countries, Portugal and the south of France, where frequent bullfighting festivals are held every year. These events can be either bullfights or what is known as encierros. Bullfights are spectacles where one or more toreros (i. e., bullfighters) fight and kill wild bulls in accordance with specific rules and methods. The spectacle i...

A model was developed for the economic evaluation of embryos for producing bull lines for use in commercial beef production. The fundamental concept underlying the model is that a cloned and sexed embryo of known genetic characteristics for beef traits is used to produce a bull. After reaching physiological maturity, the bull is used in natural matings. Equations relating feed energy requiremen...

Aim To examine the potential of bovine follicular fluid (BFF) to attract bull spermatozoa. Methods The ability of the BFF to attract bull sperm was evaluated by observing changes in sperm migration after being placed in a cross-column chamber. The movement parameters of the heads and flagella of the sperm that were attracted to the BFF were analyzed by using the Computer Assisted Sperm Analys...

BACKGROUND In male cattle, rupture of the urinary bladder is usually associated with urethral obstruction by uroliths. Less common causes include urethral compression or stricture. This case report describes the findings in a young Limousion breeding bull with rupture of the urinary bladder because of urethral compression by a haematoma after coccygeal fracture. CASE PRESENTATION The bull had...

The objective of this experiment was to determine if continuous exposure to bull urine alters resumption of ovarian cycling activity of primiparous, suckled beef cows. We tested the hypotheses that interval from urine exposure to resumption of luteal activity and proportions of cows that resume luteal activity by the end of the urine-exposure period do not differ between cows exposed to mature ...