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The aim of this study was thus to investigate the effect vacuum level on udder traits, milking time, milk yield and components in Tunisian Sicilo-Srade ewes. Trial was carried out at the UCPA farm of Gnadil-Béja (Tunisia) among 3 periods of late lactation where 3 vacuum levels (40, 50 and 60 kPa) were applied for each one. Udder traits were measured before each milking, and milking time and milk amount were recorded. Milk total solids (TS), fat, solids not fat (SNF), protein, lactose, milk urea nitrogen (MUN) and somatic cell counts (SCC) were determined. Significant effects of lactation day were observed on udder traits with the exception of teats length. Machine milking time and milk yield were the highest at the beginning of the experiment. Excepting somatic cell counts and milk urea nitrogen, the highest values of milk components were observed at the intermediate period of experiment. Significant effects of vacuum level on machine milking time and milk yield were observed, where values are the highest with the low (40 kPa) and the intermediate (50 kPa) vacuum levels, respectively. Similarly, milk solids not fat content was higher in the groups of 40 and 50 kPa than that of 60 kPa. Contrarily to protein content, milk fat obtained with 50 kPa was higher than those of 40 and 60 kPa. In conclusion, the use of a medium vacuum level of 50 kPa seems to be the suitable choice at late lactation in the dairy Sicilo-Sarde ewe with more efficient of milking performances and any detrimental effects on udder health. |
