Confinement and semi confinement of lambs in an integrated production system: impacts on production performance, infection by gastrointestinal nematodes, and selected blood analytes

ABSTRACT: This trial evaluated the production performance, gastrointestinal nematode infection (GIN), and selected blood analytes, in Corriedale lambs during the finishing phase in an integrated crop-livestock system (ICLS) with 2 stocking rates. Fifty-two Corriedale lambs were divided into 4 groups: a semi confinement system with a low stocking rate (T1) for 70 days; a semi confinement system with a high stocking rate (T2) for 70 days; confinement for 28 days, followed by semi confinement with a low stocking rate (T3) for 42 days; and confinement for 28 days, followed by semi confinement with a high stocking rate (T4) for 42 days. Body weight, dry matter intake, blood collection, and faecal analysis of nematode eggs were performed for each animal. The stocking rates did not influence body weight gain for the semiconfined lambs (T1 and T2) or for the confined/semiconfined lambs (T3 and T4). All treatments had lower EPG counts at the end of the experimental period. The nematode genera identified during the experiment trial were Haemonchus and Trichostrongylus. There were no significant differences (P > 0.05) for packed cell volume, total plasma protein, and eosinophil means between treatments. These results suggested that the confinement followed by semi confinement in an ICLS, was an option for lamb production during the finishing phase which could be useful in reducing GIN without affecting the production performance.