Season and dairy cow breed influence milk composition, cheese yielding capacity and butter properties
Résumé
A trial was carried out to study the effects of 2 feeding systems (FS) (high and low inputs FS) with 2 breeds (Holstein and Normande) and 2 genetic types ("high milk yield" type and "high fat and protein contents" type) during 2 seasons: spring and autumn. Sixty-one cows were followed. Cows were divided into 8 groups according to their breed, their genetic type and their FS. The high FS consisted of a high energy diet and the low FS consisted of a low energy di et (no concentrate ). Cheese and butter making aptitudes were tested. There were few effects of genetic types and feeding systems. Normande cows produced less milk but richer milk. Milk fat globules were larger and casein micelles were smaller. Laboratory cheese yield was better. Normande cows produced a more yellow butter. Season bad an impact on milk yield and composition due to lactation stage.