The objective of this study was to investigate the effects of partial replacement of wheat hay with sun-dried (SOC) or acid-treated SOC (ASOC) olive cake on nutrient intake and performance of Awassi lambs. An additional objective was to study the effects of acid treatment of olive cake (OC) on its chemical composition and nutritive value. On DM basis, sun-drying of OC did not dramatically affect its chemical composition. On the other hand, treating SOC with phosphoric acid decreased (p<0.05) SOC contents of neutral detergent fiber. Twenty seven male lambs (17.6±0.75 kg body weight) individually housed in shaded pens were randomly assigned to one of three dietary treatments (9 lambs/treatment). Dietary treatments were formulated to be isocaloric and isonitrogenous by replacing 50% of wheat hay in the control diet (CTL) with SOC or ASOC and to meet all nutrient requirements. Dietary treatments had no effects on nutrient intake or digestibility except for ether extract. Lambs fed the SOC diet had (p = 0.05) faster growth rate, greater final body weight, and greater total body weight gain in comparison with the CTL diet, but not different from the ASOC diet. Additionally, lambs fed the SOC diet had greater (p = 0.03) hot and cold carcass weights than the ASOC diet, but not different from the CTL diet. However, feed conversion ratios and dressing percentages were similar among dietary treatments. In conclusion, replacing half of dietary wheat hay with SOC improved performance of Awassi lambs with no detrimental effects on nutrients intake or digestibility. No further improvements in the nutritive value of SOC and lambs performance were detected when SOC was treated with acid.

Two experiments were conducted to study the effects of rumen-protected Met (RPM) alone or with rumen-protected Lys (RPL) on milk yield and plasma amino acids of dairy cows. In experiment 1, 24 multiparous Holstein cows (154 DIM) were assigned to one of 3 groups where each cow received 0 g/d of RPM and RPL (C), 30 g/d of RPM (M), or 30 g/d of RPM plus 25 g of RPL (ML). The study lasted for 8 weeks where milk yield and composition were determined weekly. Daily milk yield averaged 28·0, 27·8, and 29·7 kg/cow for the C, M, and ML groups, respectively. Dietary treatments had no effects (P ≥ 0·54) on milk contents of fat, lactose, solid non-fat or total solids. Milk protein content in the ML group was greater (P < 0·05) than the C and M groups. Plasma levels of all AA were not significantly (P ≥ 0·09) affected by supplemental RPL and/or RPM. In experiment 2, 30 multiparous Holstein cows (100 DIM) were assigned to one of 3 groups where each cow received 0 g/d of RPM and RPL (C), 50 g/d of RPM (M), or 50 g/d of RPM plus 25 g/d of RPL (ML). The study lasted for 5 weeks. Cows in the M (30·5 kg) and ML (31·4 kg) groups produced (P < 0·05) more milk than those of the C group (29·1 kg). Under conditions of this study, RPM plus RPL improved milk yield and protein contents of dairy cows and was better than supplying RPM alone. Response in milk yield to RPM and RPL was affected by the MP status of cows which deserves further investigation.

Twenty-seven Awassi lambs were used to evaluate the effects of dietary inclusion of selected (dry bread, carob pods, olive cake, and sesame meal) alternative feedstuffs (AF) on performance, carcass characteristics, and meat quality. Lambs were assigned to one of three treatment diets. Diets contained (g/kg on DM basis) no (0AF; n = 9), 250 (25AF; n = 9), or 500 (50AF; n = 9) of AF, respectively. Lambs fed the 50AF diet had the least (p < .05) intake of DM, OM, NDF, and ME. Crude protein digestibility was lowest (p < .01) in lambs fed the 50AF diet. The digestibility of NDF and ADF was highest (p < .01) for the 0AF diet. Hot and cold carcass weights tended to be greater (p ≤ .10) for lambs fed with the 0AF than the 50AF diet. Dressing percentage tended to be lower (p = .07) in lambs fed with the 50AF compared to the 0AF and 25AF diets. No substantial differences were observed among dietary treatments in carcass and non-carcass cut weights. Composition (muscle, fat, and bone) of dissected legs were not different (p ≥ .10) among dietary treatments. No substantial differences (p ≥ .37) were observed among dietary treatments in all meat quality parameters except for higher redness of the 0AF diet. Dietary inclusion of AF at 250 or 500 g/kg decreased production cost with similar feed conversion ratio. However, at high level (500 g/kg) AF could negatively affect nutrients intake, digestibility, and performance.