SANTÉ MAMMAIRE ET PERTES EN LAIT À PARTIR DES COMPTAGES CELLULAIRES INDIVIDUELS EN ÉLEVAGE BOVIN HORS SOL (TUNISIE)

Abstract

This study proposes to diagnose breast health of cows, to assess the quantitative losses in milk production and to identify risk factors for mastitis from Single Cell Counts (CCI), obtained during the period from 1 January 2009 to 30 April 2011, considering 3-10 successive checks lactation studied. The study involved 297 dairy cows (from 535 lactating cows followed), and Holstein breed, distributed in 50 small and medium farms conducted in soilless system in the region of Sousse (Tunisia). Udder health is alarming given that around 50% of cows are infected with mastitis, whatever the standard breast assessment used. Quantitative dairy losses estimated from the CCI are relatively large. For an average annual production of 5777 kg milk / cow / lactation, estimated losses may reach 1444 kg milk / cow / lactation for CCI> 200000 cell. / ml. Descriptive analysis of data on breeding and milking conditions has to demonstrate that the use of a litter reduce to the half the average CCI that have proven highly related to the cleanliness as well of the sleeping area that udder. For the milking parameters: Depth of the udder, the udder cleanliness and No teat dipping after milking have been shown to affect the CCI and were considered causal factors of bovine mastitis.