Spastic syndrome in a Canadian Hereford bull.

A 3-1/2-year-old Canadian Hereford bull was diagnosed with spastic syndrome. The disease had not been reported previously in Canadian Herefords and, in this case, it had a strong familial component with a relatively early age of onset (1 to 2 years). Signs of the disease were exacerbated while the bull was housed indoors.     

A sperm tail defect associated with infertility in a goat--case report.

Semen of an infertile Dutch White (Saanenthal) goat buck was examined. Light and electron microscopic examinations showed aberrations of the sperm tails resembling the so-called Dag or Dag-like defects described in several cattle breeds. Ejaculated semen showed that virtually all of the cells had strongly coiled or broken tails, or fractured midpieces. Ultrastructural investigations by transmission electron microscopy (TEM) showed uneven distribution of the mitochondria in the midpiece. Coiled tails were encapsulated by a common membrane, and dislocated axial fibres and different membranous structures were also present. The ultrastructural characteristics of the defective sperm tails, the missing parts of the axial fibre bundle and the misalignment of the mitochondria indicate that this first case reported in goat is similar to the Dag-like defect in cattle.     

海福特牛精液品质及保存稀释液配方研究

对饲养在三峡库区重庆境内的4头海福特牛的精液品质及标温（37℃）和低温（0～5℃）条件下精液保存稀释液配方进行了研究。结果表明:海福特公牛精液品质符合种用公牛繁殖要求,精液呈乳白色或稍带黄色,云雾状明显,采精量为（8.28±1.13）mL,pH值为7.03±0.09,精子密度为（10.67±1.67）亿/mL,活力为0.88±0.05,精子畸形率（％）为9.52±2.46。对4头公牛精液品质进行了排序,提出了常温和低温条件下适宜的精液保存稀释液配方。     

Testicular development, daily sperm production and epididymal sperm reserves in 15-mo-old Angus and Hereford bulls: effects of bull strain plus dietary energy

Bull calves (n = 143) were obtained from two strains of Angus and two strains of Hereford cattle for which replacements were selected on the basis of superior feedlot growth performance on either high- or medium-energy diets. From weaning to slaughter at 15 mo of age, bulls were fed either the high-energy (80% grain + 20% forage) or medium-energy diet (100% forage) corresponding to their strain. Bulls in high-energy diet groups had a greater (P less than .05) scrotal circumference at 12 mo, but not 15 mo of age, than bulls in medium-energy diet groups. Compared with Hereford bulls, Angus had greater (P less than .01) scrotal circumference (36.1 vs 33.9 cm) and greater (P less than .05) paired testes weight (570 vs 464 g) at 15 mo of age. Daily sperm production per gram testicular parenchyma (DSP/g) was affected by strain-diet (P less than .01) but not by breed. Bulls in medium-energy diet groups had 12% greater DSP/g than did high-energy diet bulls (17.4 X 10(6) vs 15.5 X 10(6)). Daily sperm production (DSP) was 9% and 30% greater (P less than .01) for medium-energy diet bulls in 1980 (8.2 X 10(9) vs 7.5 X 10(9)) and 1981 (8.0 X 10(9) vs 6.2 X 10(9)), respectively, compared with high-energy diet bulls. The effect (P less than .01) of breed on DSP was attributed to breed differences in paired testes weight.(ABSTRACT TRUNCATED AT 250 WORDS)     

Polyarthritis in Hereford bulls associated with BVD-MD infection

A severe and persistent polyarthritis and synovitis occurred in a group of rising two-year-old Hereford bulls associated with a transient BVD-MD-like infection.     

Detection certainty of the contamination of bull sperm with mycoplasma

Tests for presence of mycoplasmas were conducted on 20 insemination bulls known as mycoplasma spreaders, with 5 sperm pellet batches of 20 pellets each being investigated for each animal. Mycoplasma contamination was positively recorded from 83 of the above 100 batches. Mycoplasma (M.) bovigenitalium, M. californicum. M. arginini, M. bovirhinis, and Acholeplasma laidlawii were typed by means of indirect immunofluorescent technique, which confirmed the presence also in the GDR of mycoplasma species described in the literature and detected in sperm samples. The solid culturing media used in the above tests, medium-B agar and cattle blood agar with staphylococcal nutrix, proved to be equally suitable for isolation of mycoplasma from sperm samples. Mycoplasma was positively identified in about one third of all pellets/batches tested. 3 pellets to one batch should be sufficient a random sample size from which to obtain information at least very close to real contamination.     

Detection of mycoplasmas in experimentally-infected bull sperm

Bull sperm pellets experimentally infected with various concentrations of Mycoplasma (M.) bovis, M. bovigenitalium, and M. californicum were stored several months at -196 degrees C and were subsequently tested for mycoplasmas, using different methods and culturing media. M. bovis was reliably identified by laboratory diagnosis up to a concentration of 10(2) cfu/pellet. M. bovigenitalium and M. californicum were found to make higher demands on the quality of culturing substrates. Recommended are 1-h broth incubation and 5-d broth breeding.     

Cardiomyopathy associated with a curly hair coat in Poll Hereford calves in Australia

Fifteen newborn Poll Hereford calves from five farms died over a three-and-a-half year period. From birth all calves had a tight, curly hair coat which was not observed on any other calves on these properties. All calves with this phenotype died before reaching six months of age. Seven of the 15 calves were noticed to have exercise intolerance, hyperpnoea and dyspnoea for one to seven days before death. The incidence of additional features of the curly hair coat phenotype is also described. Post mortem examinations conducted on the calves revealed focal, diffuse and pale fibrous streaking of the entire myocardium and vascular congestion of the livers, spleens and lungs. A primary cardiomyopathy was diagnosed on the basis of the clinical and pathological findings. Analysis of the pedigrees of seven affected calves from one farm demonstrated a common ancestor for all sires and dams of affected calves and suggested a simple autosomal recessive mode of inheritance of the syndrome as a reasonable hypothesis for future experimental testing.     

提高种公牛精液利用率的试验研究

利用冷冻精液进行人工授精的技术在我省应用已有近三十年的历史,在推动全省牛品种改良发展方面起到了举足轻重的作用。饲养较少的种公牛生产出较多的优质冻精,即提高种公牛精液的利用率,是每个种公牛站长期以来一直追求的目标。种公牛精液冷冻效果的好坏是影响种公牛精液利用率的重要因素之一,而种公牛精液冷冻效果除受环境、气候等因素影响外,还受种公牛品种、年龄、个体等因素的影响。通过试验找出种公牛不同品种、不同年龄及不同个体对精液冷冻效果的影响,从而科学的利用种公牛精液,为有效提高种公牛精液利用率提供依据。     

Hydronephrosis and pyelonephritis associated with an anomalous vas deferens in a bull

Hydronephrosis and pyelonephritis were diagnosed in a 2-year-old Limousin bull. Salient historical and clinical observations included weight loss, anorexia, intermittent colic, polyuria, polydypsia, and an ammoniacal breath odor. Intravenous treatment with fluids and antibiotics did not induce a favorable response. An anomalous vas deferens was observed on postmortem examination. The vas deferens ended in a blind polyp that protruded into the lumen of the urethra. This polyp may have caused chronic intermittent obstruction, predisposing to the hydronephrosis and pyelonephritis.