the aim of the present study was to compare the occurrence and duration of clinical mastitis in different seasons, stages of lactation period and parities in a holstein dairy farm in iran. a retrospective epidemiological survey from april 2005 to march 2008 was conducted on 884 clinical mastitis cases of 7437 lactations. data of each case including calendar-date of mastitis onset, days in milk ...

Typically, central milk recording data from dairy herds are recorded less than monthly. Over-fitting early in lactation periods is a challenge, which we explored in different ways by reducing the number of parameters needed to describe the milk yield and somatic cell count of individual cows. Furthermore, we investigated how the parameters of lactation models correlate between parities and from...

TABLE O F CONTENTS INTRODUCTION ................................................................ I I I Material and methods ........................................................ 112 Variation of Jersey milk production with age at commencement of test.. ........ I14 Analytical constants describing the variation of milk production at different ages.. 119 The correlation of Jersey 8-months milk...