Milk yield and composition in line 05 dairy ewes as related to somatic cell counts

Abstract

A total of 1512 milk samples from udder halves was collected at monthly intervals from 189 line 05 dairy ewes throughout milking periods. Each ewe was tested 4 times. Milk composition was examined in terms of somatic cell contents (SCC) in ewe milk in three groups: group 0 consisted of ewes that on each test day had ≤250 × 10 3 cells/ml in left and right udder halves, group 1 comprised ewes with ≤250 × 10 3 in one half of the udder and >250 × 10 3 cells/ml in the other half, whereas group 2 contained ewes that had >250 × 10 3 cells/ml in the left and right udder halves (also on each test day). SCC in milk from one or both halves of udders exceeding 250 × 10 3 cells/ml resulted in a statistically significant (P<0.01), 20.7%, decrease in daily milk production.Correlation coefficients between SCC and fat and protein percentages in milk were positive and equaled 0.24 and 0.18, respectively. A negative value of the correlation coefficient was recorded between log SCC and lactose percentage (-0.49).

The relationship between somatic cells and milk traits, and their variation in dairy sheep breeds in Slovakia

“…The same pattern was found by Serrano et al (2003) and Riggio et al (2007), however these authors considered somatic cell score (SCS = log 2 (SCC/100) + 3) in analyses. Correlation coefficients between transformed SCC and milk traits obtained in our study differed from literature (Riggio et al, 2007;Olechnowicz et al, 2009): slightly stronger relationships were found for Valle del Belice ewes (correlations between SCS and daily milk yield, between SCS and fat content, and between SCS and protein content, equalled −0.12, +0.14 and +0.25, respectively) and for Polish Line 05 ewes (correlations between logSCC and fat content, between log SCC and protein content, and between logSCC and lactose content were +0.24, +0.18 and −0.49, respectively). Similarly, slightly stronger correlations were found for Manchega ewes by Serrano et al (2003).…”

“…In contrast, respective values estimated by Margetín et al (1995) for TS and IV ewes were more than two times lower. Olechnowicz et al (2009) reported log SCC · ml −1 as 5.19 for Polish Line 05 dairy sheep which fell between values estimated in this study for IV and TS ewes. Similarly, Skapetas et al (2017) estimated log SCC · ml −1 as 5.30 for Chios sheep which was almost the same as values found either for TS × LS or for IV × LC crossbred ewes.…”

“…(Burriel, 1997) and increase SCC (Pengov, 2001). Somatic cells and their relationship with milk yield and milk components were studied in sheep recently (e.g., Gonzalo et al, 1994;Olechnowicz et al, 2009;Vršková et al, 2015). Also, studies investigating associations between SCC and bacterial pathogens in ovine and goat milk were published (Hariharan et al, 2004;Bagnicka et al, 2011).…”

Somatic cell count in milk of individual lacaune ewes under practical conditions in slovakia: possible effect on milk yield and its composition

“…Especially in the farm third and fourth, with higher number of animals, there was seen high numerical decrease of milk yield between group SCC <0.2 × 10 6 cells.mL -1 and SCC >10 6 cells.mL -1 . We found out also numerical reduction of milk production in ewes with high SCC (Olechnowicz et al, 2009) there was found out significant increase of fat, protein and lactose content with increasing SCC in milk. Though not significant in this study we also confirm the decrease of lactose with high SCC in milk.…”

“…At present the somatic cell count (SCC) is considered to be a basis for abnormal milk control programs for cows, goats and sheep (Bergonier-Berthelot, 2003;Zajac et al, 2016). Higher number of SCC reduced milk production and negatively affects other variables (lactose) and positive fat and protein contents (Olechnowicz et al, 2009;Rupp et al, 2003). In spite of negative effect of SCC on milk production, in dairy ewes there is not legislative duty to analyse raw milk of ewes for SCC for the market purposes as it is in dairy cow well established.…”