Witold Rant

The Ewe’s Reproductive Performance, Growth Rate and Carcass Quality of Lambs Kept in a Barn vs Those Kept under an Overhead Shelter

A herd of polish lowland local sheep was divided into two equal groups: the first group was kept under an overhead shelter, and the second group was kept in a warm barn. The effect of maintenance on ewe’s reproductive performance, survival as well as the growth rate of lambs, and their carcasses quality was investigated. The lack of differences in fertility and prolificacy of ewes as well as in the survival and growth rate between the groups confirmed a good adaptation of Żelaźnieńska sheep to low temperature. Harsh environmental conditions did not cause a significant decrease of the body weight growth; however, they brought in an (insignificant) reduction of subcutaneous fat thickness and meatiness of the loin part of a lamb’s body. The fat content of carcasses obtained from lambs reared under the overhead shelter was significantly lower, with no differences of meat and bones contribution between the groups.

The changes in the milk composition and its lipid fraction during the rearing of lambs in non-milked sheep

The changes in the milk composition and its lipid fraction during the rearing of lambs in non-milked sheep. Studies regarding the effect of lactation stage on milk content and lipid fraction composition are mostly conducted on milked animals. The aim of this study was to analyze the changes in the basic milk composition and content of fatty acids in the fat fraction during the rearing of lambs in non-milked sheep. The study was carried out on 22 ewes of Polish lowland sheep of Żelazneńska strain, which reared lambs sold at low weight classes (up to 22 kg). Milk samples were collected at 10th (period 1), 25th (period 2) and 52nd (period 3) day of lactation. There were no differences in the amount of the basic components of milk in the studied periods of lactation beside the fat (P ≤0.05) content. There were also no difference in the content of fatty acid groups in the fat fraction of ewe’s milk examined at 10th, 25th and 52nd day of lactation. Although, in the third period of lactation, the content of saturated fatty acids (SFA) was slightly higher compared to first period. In turn, the content of oleic acid (P ≥0.30) and C18:3 (P ≤0.05) was higher in 10th day of rearing then in 52nd day. A slightly larger share of essential C18 unsaturated fatty acids in ewe’s milk in early lactation may suggest the involvement of adipose tissue in the formation of milk fat.

Assessment of slaughter value of sheep on the basis of linear measurements made on carcass digital images

Assessment of slaughter value of sheep on the basis of linear measurements made on carcass digital images. The aim of this study was to develop a method of assessing slaughter value of sheep using digital carcass images. Research material consisted of 38 ovine carcasses. Carcasses were classified in the EUROP grading system in terms of muscle and fat and photographed from three sides and then computer image analysis were used. Analyzed data of linear and area measurements of sheep carcasses using computer image analysis and compare them with the results of slaughter analysis conducted by the conventional method. To compare obtained results statistical analysis was performed. The correlation between computer linear measurements and meat cuts weight and EUROP classification were examined. The preliminary analysis showed the possibility of using computer image analysis to evaluate the meat yield of sheep, and the resulting measurements are correlated to the proportion of meat cuts and tissues, but in order to obtain high accuracy results further studies are needed.