Pasture levels of tryptophan in relation to outbreaks of fog fever.

Oral administration of tryptophan induces in cattle clinical signs and lung lesions similar to those of fog fever. Tryptophan assays were performed by a microbiological method on various herbage samples. There was no significant difference in tryptophan content between herbage from two normal pastures and from three pastures in which outbreaks of fog fever occurred.     

使用非甾体类抗炎药治疗炎症、疼痛和发烧

炎症、疼痛和发烧经常一起出现.然而,出于成本高、害怕残留和惯例,在养猪场生产中使用消炎药、镇痛和退烧药物的情况很少. 关于成本,我们必须牢记,发生疼痛和发热的动物其生产率力可能很低,因它们会减少采食量.例如,慢性疼痛不利于动物新陈代谢.这可能会引发母猪的应激,进而会导致泌乳量和繁殖率下降.此外,猪场内的大部分疾病都会引发炎症,如胸膜肺炎、支原体肺炎、支气管炎、出血性败血症、猪繁殖与呼吸道综合症、猪瘟、口蹄疫等.所以,由不使用镇疼药和消炎药节约的成本并不明显.     

Immunity following use of Australian tick fever vaccine: a review of the evidence

OBJECTIVE: To review the evidence available on the degree and duration of immunity provided by Australian tick fever vaccines against Babesia bovis, B. bigemina and Anaplasma marginale infections in Australia and overseas. BACKGROUND: Vaccines containing attenuated strains of B bovis and B bigemina as well as A. centrale grown in splenectomised calves have been used in Australia since 1964 to immunise cattle against tick fever. About 800,000 doses of vaccine are supplied annually and much of the evidence for protection is field evidence rather than conventional immunological measures or pen trials. CONCLUSIONS: Immunity to Babesia bovis and B. bigemina--A single inoculation generally provides sound, long-lasting protection both in Australia and overseas. No evidence was found of a loss of immunity with time. Vaccine failures to B. bovis do occur, but are uncommon and evidently caused by a number of factors, including immune responsiveness of the vaccinated animals, and immunogenicity of the vaccine strain. Immunity to Anaplasma marginale--The vaccine containing A. centrale provides partial, variable protection against A. marginale. Protection against challenge in Australia is adequate in most cases to prevent disease and use of the vaccine in this country appears to be justified. Protection against antigenically diverse, highly virulent stocks of A. marginale in other countries is, at times, clearly inadequate and better vaccines are required in situations where the challenge is severe.     

玉米高烧难退反季节上涨成立

2007/08年度,玉米以它特有的魅力再次上演了一次反季节上涨。这次似乎占据了天时、地利、人和,理所当然地越走越远,超出了市场的预期。对此,市场人士大都认为反季节上涨成立。企业不能无米下炊,还要采购。     

Immunological injury in "shipping fever" pneumonia of cattle.

Electron opaque deposits were found on the alveolar capillary walls, luminia of alveolar capillaries, subendothelium and interstitium of four out of 10 Holstein dairy cattle with past shipping histories. The deposits were positive for anti-IgG bovine immunoglobulin by fluorescent antibody technique. Evidence is presented that antigen antibody complexes may play an important role in bovine respiratory diseases.