We conducted a meta-analysis in this scientific study to determine the effects of feeding meat sheep dry distillers grains with solubles (DDGS). Thirty-three peer-reviewed articles that met our inclusion requirements and were published between 1997 and 2021 were examined. To calculate the variation in performance, fermentation, carcass features, and nitrogen efficiency between the DDGS and control (no DDGS) treatments, we used 940 sheep weighing an average of 29.1 ± 1.5 kg. We used a hierarchical mixed model to conduct a meta-regression, subset, and dose–response analysis, while taking into consideration categorical variables like breed (pure or cross-breed), and continuous factors, like CP, NDF, and DDGS inclusion rate. Our findings indicate that sheep fed DDGS had higher (p < 0.05) final body weight (51.4 vs. 50.4 kg), neutral detergent fiber digestibility (55.9 vs. 53.8%), and total-tract ether extract digestibility (81.7 vs. 78.7%) than sheep on a control diet. No effects were observed on DMI, CP, and rumen fermentation, but dietary DDGS tended to increase (p = 0.07) HC weight (25.53 vs. 24.6 kg) and meat (redness) color (16.6 vs. 16.3) among treatment comparisons. Dietary DDGS was associated with higher N intake (29.9 vs. 26.8 g/d), fecal N (8.2 vs. 7.8 g/d), and digestibility (71.9 vs. 68.5%). Urinary nitrogen was significantly (p < 0.05) affected linearly by increasing the intake of DDGS in the diet. Based on the dose–response analysis, dietary DDGS inclusion should not exceed 20% to avoid negative effects on performance, nitrogen metabolism, and meat color. Dietary protein from DDGS should not exceed 17% to prevent reduced TVFA concentrations. Breed strongly influenced (p < 0.05) RMD in performance, and inconsistent responses were observed between crossbreed and purebred sheep comparisons. Despite these inconsistencies, no publication bias was observed, but a high variance (Ω2) among comparisons-between-studies was detected. This meta-analysis showed evidence in support of the hypothesis that feeding meat sheep DDGS at a rate of 20% can improve their performance, digestibility, carcass weight, and meat color.

Infertility is a major cause of economic losses in livestock production systems. Parasitic infections are a significant cause of infertility in small ruminants. Sericea lespedeza (SL; Lespedeza cuneata) is a potent anthelmintic in sheep and goats. Positive impacts of lespedeza on male fertility have been reported in rats and rabbits; however, no studies have been conducted on goats. Here, we investigated the effects of feeding male goats with SL or annual lespedeza (AL; Kummerowia stiulacea) on their semen quality and fertility. Forty-nine mature intact Spanish bucks were randomly assigned into three groups and fed diets of 60% hay and 40% concentrate in an 8-week pen study. The treatment hays were SL (n=16), AL (n=17), and bermudagrass (Cynodon dactylon) as a control (n=16). At the end of the trial, scrotum circumferences (SC) were measured and the animals were transported to a processing facility for slaughtering. Testicles and epididymides were collected after slaughter for measuring their weights and lengths. Epididymal spermatozoa were retrieved and evaluated for their motility, concentration, viability, abnormalities, and membrane integrities. Sections from testicles and epididymides were also prepared for histopathological examination. Results showed that SC was higher (P≤ 0.05) in SL than AL groups. Testicular and epididymal weights were comparable (P > 0.05) among the three groups. Sperm motility, concentration, viability, and membrane integrities were higher (P≤ 0.05) in SL compared with the AL and control groups. Sperm abnormalities were higher (P≤ 0.05) in control and AL groups than in the SL group. Histopathological examination revealed mild focally extensive seminiferous tubular degeneration and necrosis in AL group. These results suggest that feeding of male goats on SL enhances their sperm quality and fertility parameters.

We conducted a meta-analysis to evaluate the effects of dietary supplementation of dry distillers grains with solubles (DDGS) on performance, fermentation, carcass characteristics, and nitrogen efficiency in meat sheep. A total of 36 peer-reviewed manuscripts from 1997 to 2021 met the inclusion criteria for the analysis. Data from 940 sheep (29.1±11.5 kg) were used to estimate the magnitude of the effect between DDGS and control (No DDGS) treatments weighted by inverse variance using a robust variance estimation. Categorical and continuous covariates, like breed (pure or crossbreed), CP, NDF, and DDGS inclusion rate (0 to 100%) were adjusted to a mixed model to perform a meta-regression and subset analysis. Dietary DDGS increased (P < 0.05) dry matter digestibility (75.9 vs.74.9 %), neutral detergent fiber digestibility (55.9 vs. 53.8%) with respect to the control. Compared with the control, dietary DDGS increased (P < 0.01) final body weight (51.4 vs. 50.4 kg) and tended to increase (P = 0.06) average daily gain (254.1 vs. 247.6 g/d) in sheep. Similarly, dietary DDGS tended to increase (P < 0.10) hot and cold carcass weight (25.5 vs. 24.6 kg; 21.1 vs. 19.8 kg), and meat redness (16.3 vs. 16.6) compared with the control. Dietary DDGS reduced acetate molar proportions (50.1 vs. 52.0%) and acetate: propionate ratio (1.63 vs. 1.87; P = 0.02). The subset analysis revealed that breed and DDGS levels in the diet influenced yield grade and carcass weight. Dietary inclusion of DDGS linearly increased (P < 0.05) nitrogen intake and rumen NH3-N, but also urinary nitrogen. The inclusion rate of DDGS should not exceed 30% in the diet to prevent negative effects on nitrogen metabolism, rumen fermentation, and carcass characteristics in meat sheep. Collectively, this study supports the inclusion of DDGS in meat sheep diets to increase performance and meat quality.

Infection with internal parasites is the primary constraint to profitable small ruminant production systems world-wide. Perennial lespedeza (Lespedeza cuneata) has been used as a nutraceutical (nutritional + pharmaceutical) forage for livestock, with very good bioactivity against gastrointestinal nematodes (GIN) and coccidia (Eimeria spp.) in sheep and goats, but the anti-parasitic bioactivity of annual lespedeza (Kummerowia stiulacea) has not been documented. An 8-week pen feeding trial was completed with yearling Spanish intact bucks (38.3 ± 3.6 kg) fed 3 treatment diets (n = 15/treatment) of 60% hay and 40% concentrate, with diets balanced for CP and energy. Hay treatments were ground ‘Korean’ annual lespedeza (AL), ‘AU-Grazer’ sericea lespedeza (SL), and bermudagrass (Cynodon dactylon). Blood and fecal samples were taken every 7 days throughout the study to determine packed cell volume (PCV) and GIN fecal egg counts (FEC) and coccidia fecal oocyst counts (FOC), respectively. Body weights (BW) were taken at the start and end of the trial. Data were analyzed as a completely randomized design with repeated measures. There was no effect of treatment, time, or treatment x time interaction on BW or PCV of the goats. Both FEC and FOC were impacted by a treatment by time interaction (P < 0.05). For FEC, AL goats were different from CON at all time points, but the SL group was only different from CON at d 14, 21 and 49. The AL and SL groups were different at days 35, 42 and 49 only. For FOC, AL was only different (P < 0.03) from CON on day 49, SL different from CON on day 42 and 49 and AL different from SL on day 42 only. Korean AL had similar anti-parasitic bioactivity as AU-Grazer SL in goats, suggesting a larger role for AL as a nutraceutical forage for livestock.