No abstract

The objective of this work was to study the effect of the supplementation of dairy ewes' diet with liquid methionine (ALIMET) on milk yield and milk composition, from late pregnancy to mid lactation period. Sixty 3-4 year old Boutsiko breed lactating dairy ewes with an average initial body weight 48±1.7 kg and good body condition (3.6), were divided into three groups (treatments), balanced according to milk yield. Ewes were fed 0.8 kg alfalfa hay and 0.8 kg of concentrate daily. Ewes in Group A were fed a usual concentrate for lactating ewes (control), in Group B the control concentrate +1 g ALIMET /kg concentrate, and in Group C the control concentrate +3 g ALIMET /kg concentrate. Ewes were milked twice daily, and milk weights (yield) were recorded every 4 weeks, while milk samples were taken, on a percent basis (10%), for compositional analysis. The results showed that the inclusion of ALIMET significantly increased (p<0.05) milk yield (by 6.8% in Group B and 12% in Group C), compared to control, FCM (6% fat) yield (by 5.5% in Group B and 13.6% in Group C), and milk fat, protein and non fat solids. The growth rate of lambs was 7% and 8% higher, for the suckling period of 42 days, for the Groups B and C, respectively, compared to control, but those differences were not significant. The average daily body weight change of ewes during the experimental lactation period was +0.6, +1.0 and-0.2 kg for Groups A, B and C, respectively. Thus, supplementing the ewes' diet with ALIMET, at a level of 3 g /kg concentrate, had a positive effect on milk yield and milk composition.

Twenty-four Boutsiko breed lambs were allocated to three groups of equal average live weight (LW: 20.8 kg) and pastured at three stocking rates: SR1, SR2 and SR3 (representing 60, 80 and 100 lambs/ha respectively) under low-input farming practices. Animals were grazed on a semi natural sward daily, during a 60 days period. Sward height in all treatments remained above 7 cm during the trial and the herbage gross chemical composition was similar between treatments. On average, the lambs grazed 372 min, ruminated 140 min and spent 88 min on other non-feeding activities during the daily pasturing. Lambs consumed at the start and the finish of the trial 714 g and 1014 g of herbage DM/day, or 70.5 and 99.0 g/kgW0.75/day respectively. Herbage DM digestibility (in vivo) was moderate averaging 61% and no differences were observed between the three groups of lambs. The daily live weight gain of lambs (DLWG) was different (p<0.01) between the stocking rates, where lambs on plot SR1 had the highest gain (0.0918 kg LW/day) and lambs on SR2 and SR3 plots the lowest gain (0.0344 and 0.0531 kg LW/day respectively). Faecal egg counts (FEC) for gastrointestinal parasites (GIN) from lambs grazing plot SR3 were low, while high numbers of Moniezia spp. eggs were present in faecal samples of all groups of lambs at the end of the experiment. It is concluded that lamb fattening on pasture can be achieved at reasonable stocking rates, without the use of anthelmintics, if a local hardy breed is used.