香蕉牛奶.ppt.ppt

Seasonal changesin somatic cell contentin milk of PolishHolstein-Friesian cows Maciej Gierdziewicz The Faculty of Animal Sciences Agricultural University in Cracow Somatic cells in milk Somatic cells in milk (2) Healthy cow – SCC up to 100 000 /ml SCC depends on lactation number: 1st lactation cow – up to 35 000 /ml 2nd lactation cow – up to 50 000 /ml 3rd lactation cow – up to 60 000 /ml Cow with (sub)clinical mastitis – SCC 500 000 5 000 000 50 000 000 ? COUNCIL DIRECTIVE 92/46/EEC,16 June 1992: Health rules for the production and placing on the market of raw milk, heat-treated milk and milk-based products COUNCIL DIRECTIVE 92/46/EEC16 June 1992 (continued) Rozporz?dzenie Ministra Rolnictwai Gospodarki ?ywno?ciowejz dnia 29 wrze?nia 1999 r.(Polish regulations) Transformation of SCC to SCS Selected referencesI. General Selected referencesII. Age, test month, % of HF genes Selected referencesIII. Days in milk (in Polish cattle) The goal Data (1) Data (2)average SCS by month of calving - lactations I - III Data (3)average SCS by month of test - lactations I - III Methods (1) Methods (2) Hardware Software Technical remarks Results for 1st lactation (1)grid search - residual sum of squares for phase shift = +1month Results for 1st lactation (2)grid search - residual sum of squares for phase shift = +1.5 months Results (3) - analysis of varianceeffect of month of test - 1st lactation Results (4) – SCS vs month of calving Results (5) – SCS vs month of test Conclusions * 鲜奶吧 In cattle breeding, the number of somatic cells in milk (Somatic Cell Count - SCC) is a commonly accepted indicator of subclinical mastitis. 天津电线电缆 电力电缆 低烟无卤电缆 ? [...] CHAPTER IV Standards to be met for collection of raw milk [...] A. Raw cows milk [...]” ?Somatic cell count (per ml) 400 000 (b) (b) Geometric average over a period of three months, with at least one sample a month, or, where production levels vary considerably according to season, method of