18-24 h after parturition, 20 Comisana lambs were separated from their dams and were subsequently offered a commercial milk substitute (Sub) or were subjected to a gradual transition from maternal to reconstituted milk over 10 days (Mix). Lambs had free access to milk for 3 h a day. A further 10 lambs remained with their dams and were suckled (control). At 21 days of age, all groups were supplemented with alfalfa hay and concentrates. In vivo cell-mediated immune response of lambs to phytoheamagglutinin percutaneous injection was evaluated at 5, 15 and 25 days of age. At 10 and 20 days of age, all lambs were subjected to 15 min isolation tests, during which latency time to move, duration of movement and number of bleats were recorded. Blood samples were collected immediately before and 15 and 60 min after the test. In addition, weight gains of all lambs and milk intakes of test lambs were recorded during the first 35 days at weekly intervals. The Sub group had a lower immune response (P<0.01) and, at 10 days of age, increased levels of plasma cortisol (P<0.001) as well as a reduced duration of movement (P<0.001) and a longer latency time to move (P<0.001) than the control and Mix groups. There were no significant differences between the control and Mix groups for immune, cortisol and behavioural responses. Mix lambs consumed more milk (P<0.006) and had higher weight gains (P<0.001) than Sub lambs. However, Mix lambs gained less weight on average (P<0.05) than controls.
|Publication Title||Applied Animal Behaviour Science|
|Author Address||Istituto di Produzioni e Preparazioni Alimentari, Universita di Bari, via Napoli, 25, 71100 Foggia, Italy.|
|Cite this work||
Researchers should cite this work as follows: