摘要:

Extract

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35264

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Serum inorganic phosphorus (Pi) concentration of 20 cows in each of ten factory supply dairy herds was assessed at monthly or two-monthly intervals during the 1982–83 lactation. Pasture on offer was ranked low, medium or high and the phosphorus (P) content assessed monthly on all farms from the two paddocks to be grazed next in the rotation. The mean serum Pi concentration was high (1.98 mmol/1) prior to calving but fell to low levels at peak lactation (1.28 mmol/1) and again during the drought (1.28–1.38 mmol/1) in January, February and March. Individual cows had Pi levels as low as 0.32 mmol/l. Herds on Northern Yellow-brown Earths had higher Pi levels than herds predominantly on Brown Granular Loams (P<0.01). There were differences between cows within herds (P<0.01) and Pi levels declined with cow age (P<0.01). Pasture P content was above minimum requirements for lactating cows (0.33% DM; withad lib. feeding) from July through October but below requirements in most pastures from December through April, when pasture availability also limited production. The P content in pasture was unrelated to either its grass or legume content, but was higher in pastures given a medium or high DM ranking (P<0.05). The possibility of increasing dairy production with P supplementation in spring is discussed.

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35265

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

An indirect enzyme linked immunosorbent assay (ELISA) procedure was evaluated against the serum neutralisation test (SNT) for the detection of antibodies to infectious bovine rhinotracheitis virus (bovine herpesvirus type 1), using 2028 sera from 166 dairy and 172 beef cattle herds. The results showed the ELISA to give high levels of agreement with the SNT in classifying positive and negative sera (98% and 97% respectively). Such disagreements as did occur involved weakly reactive sera with SNT titres of 1/4 or less. A number of sera (n=123) with trace neutralising activity of doubtful diagnostic significance were found to give marginal reactivity with ELISA. ELISA absorbance values were found to be highly correlated with SNT titres (r=0.909) on an overall basis, though agreements were lower with individual sera. The ELISA procedure was quicker, cheaper, and detected more reactors than the SNT. It also allowed results to be obtained with a number of sera which were unsuitable for testing by SNT because of their cytotoxic nature.

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35266

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Approximately 30% of 750 neonatal farmed ferret kits died without observed clinical signs. The presence of multifocal necrosis associated withToxoplasma-like organisms in the liver, lung and heart suggested a diagnosis of toxoplasmosis. Surviving animals from affected litters were stunted but showed no histological or serological evidence ofToxoplasmainfection, nor could infection be demonstrated by mouse inoculation. The involvement of animals at one day of age indicated congenitally acquired disease.

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35267

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Extract

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35269

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Extract

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35270

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Extract

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35272

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Extract

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35273

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Extract

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35274

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor

摘要:

Extract

ISSN:0048-0169    

DOI:10.1080/00480169.1986.35275

出版商:Taylor & Francis Group    

年代:1986

数据来源: Taylor