The effects of Saccharomyces cerevisiae supplementation on intake, nutrient digestibility, and rumen fluid pH in Awassi female lambs

Aim: The aim of this study was to evaluate the effect of feeding low (LO)- or high (HI)-fiber diets supplemented with Saccharomyces cerevisiae (SC) on nutrient intake, digestibility, nitrogen balance, rumen fluid pH, and serum concentrations of glucose and urea nitrogen in Awassi female lambs in a 2×2 factorial arrangement of treatments. Materials and Methods: Experimental diets were as follows: (1) LO-fiber diet with no SC supplementation (-LO), (2) LO-fiber diet supplemented with SC (+LO), (3) HI-fiber diet with no SC supplementation (-HI), or (4) HI-fiber diet supplemented with SC (+HI). Eight female lambs were used in a replicated 4×4 Latin square design with 15-day experimental periods (10-day adaptation period and 5-day collection period). Results: A fiber×SC interaction (p≤0.05) was detected for dry matter (DM) and crude protein (CP) intake among diets showing greater DM and CP intake for +LO diet compared to +HI group supplemented with SC, whereas -LO and -HI were intermediate. A fiber×SC interaction (p=0.05) was also detected for the neutral detergent fiber (NDF) intake among diets. Intake of NDF was greater for the -HI diet compared with +LO and -LO diets. Similarly, NDF intake was greater for +HI diet than -LO diet. A tendency (p=0.07) for a fiber×SC interaction was detected for acid detergent fiber (ADF) intake among diets as well. ADF intake tended to be greater for HI-fiber diets. No difference was observed in the rumen fluid pH for lambs fed with the different diets. No fiber×SC interactions were detected for the digestibility of DM, CP, NDF, and ADF among dietary treatments. Digestibility of DM was greater (72.9 g/100 g vs. 67.1 g/100 g; p=0.0002) for LO versus HI fiber. However, NDF and ADF digestibilities were greater (60.8 and 61.9 g/100 g vs. 55.8 and 52.7 g/100 g for NDF and ADF digestibility, respectively; p≤0.01) for the HI-fiber than the LO-fiber diets. Conclusion: Results obtained in the current study indicate that SC supplementation has a minimal effect on the performance of Awassi female lambs fed with varying fiber levels

The effects of progesterone priming on reproductive performance of GnRH-PGF2α\alpha-treated anestrous goats

The objective of this experiment was to determine the effect of a 5-day progesterone priming prior to a GnRH-PGF2$\alpha$ treatment on reproductive performance of anestrous goats. Thirty-six Mountain Black goats were randomly assigned in a 2 × 2 factorial arrangement and were administered intravaginally on day –12, either with 300 mg progesterone inserts (CGPE and CGP) or with 0 mg progesterone (GPE and GP) for 5 days. On day –6, the goats were injected with 100 $\mu$g GnRH, followed 6 days later by 15 mg PGF2$\alpha$ (day 0), the time at which the goats in the CGPE and GPE groups were administered 300 IU eCG injections and those in CGP and GP groups were administered the control solution. The goats were exposed to four fertile bucks at 0 h and were checked for breeding marks at 6-h intervals for 72 h. Blood samples were collected from all goats for progesterone analysis. Progesterone concentrations increased only in CGPE and CGP during the period of device insertion but remained low in GPE and GP groups (P < 0.001). Progesterone levels at the time of GnRH injection on day –6 were basal (0.2 ± 0.04 ng·mL–1) among the groups and began to increase starting on day –2. Day 0 progesterone concentrations differed (P < 0.05) among groups and were significantly influenced by CIDR-G (P < 0.001). A similar proportion of goats expressed estrus and intervals to detected estrus were shorter (P < 0.05) in the CGPE and GPE groups than in GP with no difference between the CGPE, CGP and GPE or between CGP and GP groups. The number of goats ovulating based upon elevated progesterone levels on day 0 was significantly greater (P = 0.002) in CGPE (9/9) and CGP (9/9) than GPE (6/9) and GP (5/9) groups and was significantly influenced by CIDR-G (P = 0.03). All pregnant goats had elevated progesterone concentration on day 0 and none of the goats with basal progesterone levels became pregnant. Pregnancy and kidding rates, twinning percentage and the number of kids born per goat exposed were greater (P < 0.05) among goats treated with progesterone and eCG. In conclusion, progesterone priming and eCG are essential for producing higher rates of pregnancy and kidding in GnRH-PGF2$\alpha$-treated anestrous goats

Replacing Soybean Meal with Sesame Meal in the Diets of Lactating Awassi Ewes Suckling Single Lambs: Nutrient Digestibility, Milk Production, and Lamb Growth

Two experiments were conducted to assess the influence of sesame meal (SM) feeding on nutrient digestibility, N balance, milk production and composition, ewes&#8217; body weight change, and growth performance of lambs. In experiment 1, 18 ewe lambs were randomly distributed into three diets to evaluate the effects of soybean meal replacement with SM on nutrient intake, digestibility, and N balance. Treatments were no SM (SM0), 7.5% SM (SM7.5), or 15% SM (SM15) of the dietary dry matter (DM). Aside from intake and digestibility of ether extract (EE), which was greater in the SM-containing diets compared with SM0, intake and digestibility of the remaining nutrients was similar among dietary treatments. In experiment 2, 30 ewes suckling single lambs were randomly assigned to the same diets used in experiment 1. Intakes of DM, crude protein, neutral detergent fiber, and acid detergent fiber were unaffected by treatment. Milk yield was greater in SM diets than in the SM0 diet. Cost/kg of milk production decreased while feed efficiency improved in the SM-diets compared to the SM0 diet. In conclusion, results of the current studies demonstrate the possibility of replacing soybean meal with sesame meal in diets of lactating Awassi ewes