1. Ram and bull spermatozoa suspended in a glucose-sodium chloride solution rapidly lose motility at relatively high dilutions. The substitution of chloride-free diluents does not alter the phenomenon. 2. The rapid immobilization of ram and bull spermatozoa due to high dilution may be partially prevented by the addition of supernatants of either ram or bull semen, although motility is not maint...

We give a polynomial-time algorithm that computes the chromatic number of any graph that contains no path on five vertices and no bull as an induced subgraph (where the bull is the graph with five vertices a, b, c, d, e and edges ab, bc, cd, be, ce).

The aim of the study was to evaluate the effect of the addition of 20% bull seminal plasma to semen extenders on post-thaw sperm motility, morphology, and fertility. Two Merino rams at 3-5 years of age, 43 ewes, and one Holstein bull were used. Fourteen ejaculates were collected by the use of an artificial vagina, twice a day, at 60 min interval. Six semen ejaculates were extended with Tris-egg...

The ties and relationships within the Ayrshire and Jersey bull populations from the United States and Canada were investigated. Twenty-two percent of genes in the United States Ayrshire bull population were of Canadian origin, whereas 22% of genes in the Canadian Jersey bull population were of United States origin. Average genetic relationships among bulls between countries were comparable with...

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...