Effect of Vacuum Level on Udder Aspect and Milking in the Sicilo-Sarde Ewes - Abstract
The study aimed to investigate the effect of vacuum level on udder traits, milking time, milk yield, and components in Tunisian Sicilo-Srade ewes. The trial
was carried out at the UCPA farm of Gnadil-Béja (Tunisia) among three 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. Results showed significant effects of lactation day on udder
traits with the exception of teats length. Machine milking time (32.75 sec) and milk yield (0.78 L/ewe/d) 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 the experiment.
Significant effects of vacuum level on machine milking time and milk yield were observed (P<0.05), 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.