Effect of substituting barley with sorghum on starch digestion, rumen microbial yield and growth in Iranian Baluchi lambs fed high concentrate diets

Effect of dietary concentrate level on digestibility of nutrients in each region of the gastrointestinal tract and rumen fermentation in goats

This study evaluated the effects of high concentrate diets (HCD) on the rumen fermentation and the digestibility of nutrients in different sites of the gastrointestinal tract (GIT) in goats. Four goats were used in a crossover design. The goats were fitted with a ruminal cannula and flexible T-cannulae proximal duodenum and terminal ileum. Treatments were as follows: low concentrate group (LCG) and high concentrate group (HCG). Duodenal flow and forestomach digestibility of starch were significantly higher in the HCG than those in the LCG (p < 0.05); There was no significant difference in ileum flow and digestibility of starch in the small intestine, large intestine and total GIT (p > 0.05). The digestibility of crude protein (CP) in the forestomach was significantly higher in the HCG than in the LCG (p < 0.05); the flow of the duodenum and ileum of CP, and the CP digestibility of the small intestine, large intestine and total GIT were not significantly different between groups (p > 0.05). The duodenal and ileal flow of neutral detergent fiber (NDF), the NDF digestibility of the different segments and total GIT were not significantly different between groups (p > 0.05). Compared to the LCG, the ruminal pH of the HCG was significantly lower (p < 0.05). The HCG concentrations of microbial crude protein, ammonia nitrogen and isovaleric acid were significantly higher (p < 0.05) than the LCG. The foam strength, foam production and viscosity of the rumen fluid in the HCG were higher than the LCG (p < 0.01). These results showed that when the goats were fed with HCD, the digestibility of nutrients was not significantly impaired, but the risk of frothy rumen bloat increased. ImplicationsDue to a serious shortage of high-quality roughage in China, producers commonly used a high-concentrate diet in ruminants, which can improve animal production performance.Gastrointestinal digestive function plays a vital role in the absorption of nutrients and the healthy growth of animals.Therefore, this research evaluated the digestibility of various nutrients in different segments of the gastrointestinal tract (GIT) under HCD feeding by using three-site cannula goats as experimental animals.The results indicated that the GIT of goats could fully digest nutrients such as starch and protein under HCD feeding conditions.

Rumen-Protected Lysine and Methionine Supplementation Reduced Protein Requirement of Holstein Bulls by Altering Nitrogen Metabolism in Liver

The aim of this study was to investigate the effect of low-protein diets supplemented with rumen-protected lysine (RPLys) and methionine (RPMet) on growth performance, rumen fermentation, blood biochemical parameters, nitrogen metabolism, and gene expression related to N metabolism in the liver of Holstein bulls. Thirty-six healthy and disease-free Holstein bulls with a similar body weight (BW) (424 ± 15 kg, 13 months old) were selected. According to their BW, they were randomly divided into three groups with 12 bulls in each group in a completely randomized design. The control group (D1) was fed with a high-protein basal diet (CP13%), while bulls in two low-protein groups were supplied a diet with 11% crude protein and RPLys 34 g/d·head + RPMet 2 g/d·head (low protein with low RPAA, T2) or RPLys 55 g/d·head + RPMet 9 g/d·head (low protein with high RPAA, T3). At the end of the experiment, the feces and urine of dairy bulls were collected for three consecutive days. Blood and rumen fluid were collected before morning feeding, and liver samples were collected after slaughtering. The results showed that the average daily gain (ADG) of bulls in the T3 group was higher than those in D1 (p < 0.05). Compared with D1, a significantly higher nitrogen utilization rate (p < 0.05) and serum IGF-1 content (p < 0.05) were observed in both T2 and T3 groups; however, blood urea nitrogen (BUN) content was significantly lower in the T2 and T3 groups (p < 0.05). The content of acetic acid in the rumen of the T3 group was significantly higher than that of the D1 group. No significant differences were observed among the different groups (p > 0.05) in relation to the alpha diversity. Compared with D1, the relative abundance of Christensenellaceae_R-7_group in T3 was higher (p < 0.05), while that of Prevotellaceae _YAB2003_group and Succinivibrio were lower (p < 0.05). Compared with D1 and T2 group, the T3 group showed an expression of messenger ribonucleic acid (mRNA) that is associated with (CPS-1, ASS1, OTC, ARG) and (N-AGS, S6K1, eIF4B, mTORC1) in liver; moreover, the T3 group was significantly enhanced (p < 0.05). Overall, our results indicated that low dietary protein (11%) levels added with RPAA (RPLys 55 g/d +RPMet 9 g/d) can benefit the growth performance of Holstein bulls by reducing nitrogen excretion and enhancing nitrogen efficiency in the liver.

Effects of Dietary Barley Starch Contents on the Performance, Nutrient Digestion, Rumen Fermentation, and Bacterial Community of Fattening Hu Sheep

The objective of this experiment was to investigate the effects of substituting corn starch (CS) with barley starch (BS) on the growth performance, nutrient digestion, rumen fermentation, and bacterial community of fattening Hu sheep. Seventy-two Hu lambs with similar initial body weight (BW, 29.70 ± 1.70 kg) were randomly assigned to four treatments, with 18 lambs per group. The four experimental diets have identical starch contents but with different starch sources as 100% starch from corn (BS-0), 33% starch from barley and 67% starch from corn (BS-33), 67% starch form barley and 33% starch from corn (BS-67), and 100% starch from barley (BS-100). All lambs were reared in individual units and fed high-concentrate diets (85% concentrate in diets based on dry matter [DM]). The experimental period included 7 days for adaptation and 63 days for data collection. Sixteen ruminal cannulated Hu sheep were divided into 4 groups and received the four experimental diets to determine the dynamics of ruminal pH. The average daily gain (ADG), and BW gain of lambs linearly decreased (p &lt; 0.05), whereas the feed to gain ratio linearly increased (p &lt; 0.05) with increasing dietary proportions of BS. Digestibility of DM, organic matter, neutral detergent fiber, acid detergent fiber, starch, and gross energy (GE) decreased (p &lt; 0.05) with increasing dietary BS contents. Ruminal mean pH decreased (p &lt; 0.05) with increasing proportions of dietary BS, accompanied with linearly increased (p &lt; 0.05) time and area of ruminal pH below 5.80 or 5.60. Increasing dietary proportions of BS linearly decreased (p &lt; 0.05) the molar proportion of acetate, but linearly increased (p &lt; 0.05) the molar proportion of propionate. Sheep of the BS-0 and BS-33 treatments had a less (p &lt; 0.05) relative abundance of Selenomonas ruminantium than that of sheep of the BS-67 treatment, but a greater (p &lt; 0.05) relative abundance of Ruminococcus albus than that of sheep of the BS-100 treatment (p &lt; 0.05). In conclusion, feeding a high-concentrate corn-based diet for fattening Hu sheep improved the performance and rumen fermentation parameters when compared to the barley-based diet.

Effect of energy supplementation on intake, digestibility of diets and performance of grazing lambs during the rainy season

This study aimed to evaluate different energy sources in multiple supplements on performance, intake, and digestibility of Santa Ines sheep grazing urochloa grass (Urochloa mosambicensis) during the rainy season. The experimental area was divided into seven paddocks of 4 ha each, with an average of dry matter (DM) availability of 3.21 tn/ha. A completely randomized design was carried out, in which there were four treatments, and each treatment was repeated six times. Twenty-four intact lambs (average: 32.0 kg of body weight) were supplemented with a mineral mixture, the control group (MM), mesquite pod meal (MPM), wheat bran (WB), or sorghum grain (SG) as energy sources. The digestibility of DM and crude protein (CP) in MPM and WB is higher than that in MM and SG groups. Neutral detergent fiber (NDF) digestibility was similar between supplemented lambs, and it was higher than the MM. The supplementation promoted higher weight gain than in the control group (0.126 vs. 0.061 g/day, respectively; P < 0.001). The supplementation increased the DM, and CP intake. The NDF intake only increased in the WB group. The CP digestibility was higher for the MPM and WB groups than that for MM and SG ones (P < 0.001). Sheep supplementation in the rainy season increased the average daily gain (ADG). Any supplement tested in the present study can be used during the rainy season. The choice for the supplement will depend on the availability and costs of the mesquite pod meal, sorghum grain, or wheat bran.

Effects of grain type and conditioning temperature during pelleting on growth performance, ruminal fermentation, meat quality and blood metabolites of fattening lambs

Ruminants can tolerate moderate concentrations of dietary tannin, making it feasible to replace corn with sorghum in ruminant diets; however, conditioning temperature of pelleted total mixed ration (PTMR) greatly affects nutrient digestibility. The objective was to determine effects of grain type and conditioning temperature during pelleting on growth performance, ruminal fermentation, meat quality and blood metabolites of fattening lambs. This was a 2 × 3 factorial study, with corn and sorghum and three conditioning temperatures (65, 75 and 85 °C) in a randomized complete design, with 36 lambs (120 ± 10.2 d and 24.9 ± 3.3 kg) grouped by weight and randomly allocated. The resulting six PTMRs were referred to as 65-S, 75-S and 85-S for sorghum-based diets, and 65-C, 75-C and 85-C for corn-based diets, for low, medium and high pelleting temperatures, respectively. There was no grain type × conditioning temperature (Grain × Temp) interaction on growth performance and apparent nutrient digestibility. Furthermore, grain type did not affect DM intake (DMI), average daily gain (ADG) or feed conversion ratio (FCR) of fattening lambs. Pelleting at 75 °C improved ADG (P < 0.03) and FCR (P < 0.02) of fattening lambs compared to other temperatures. There was a Grain × Temp interaction (P < 0.01) on ruminal pH (lowest in lambs fed 75-S). There tended (P = 0.07) to be a Grain × Temp interaction for total volatile fatty acid (VFA), and there were Grain × Temp interactions for molar proportions of acetate (P < 0.04), butyrate (P < 0.03) and branch-chained VFA (P < 0.01). Lambs fed sorghum-based PTMR had greater molar proportion of propionate (P < 0.03) and lower acetate to propionate ratio (A:P, P < 0.04). Lambs fed sorghum-based PTMR had higher plasma concentrations of urea nitrogen (N) (P < 0.03), glucose (P < 0.01) and alkaline phosphatase (P < 0.05), whereas other blood metabolites were not affected by treatments. There were Grain × Temp (P < 0.03) interactions for color coordinates of longissimus and mid-gluteal muscle. Lambs fed sorghum-based PTMR had lower (P < 0.01) dressing percentage and meat quality than those fed corn-based PTMR. We concluded that sorghum can replace corn in lamb diets without compromising growth performance and feed efficiency; furthermore, feeding sorghum vs corn improved rumen fermentation, with reduced A:P ratio and enhanced N and glucose utilization. Finally, pelleting at 75 °C increased feeding value of either sorghum- or corn-based PTMR for fattening lambs.

Effect of calcium lignosulfonate supplementation on metabolic profiles of confined lambs

This study aimed to evaluate the effect of calcium lignosulfonate associated with whole cottonseed in high-concentrate diets for sheep. Eight Dorper crossbred sheep with an average live weight of 42.5 ± 1.70 kg were assigned to two 4 × 4 Latin squares. The following experimental diets were evaluated: control diet (without calcium lignosulfonate) and diets with inclusion of 50, 100, and 150 g of calcium lignosulfonate/kg fresh matter. Diets were composed of soybean meal, ground corn, and whole cottonseed. Feed intake, digestibility, metabolic characteristics, and feeding behavior were evaluated. The intake of nutritional components did not show significant differences as a function of the lignosulfonate levels in the diet; however, the increase in calcium lignosulfonate levels linearly decreased the dry matter digestibility. Rumen ammonia nitrogen concentrations decreased linearly as the lignosulfonate levels in the diets were increased. There was no effect of lignosulfonate levels on blood parameters or feeding behavior of the animals. The use of lignosulfonate associated with cottonseed decreases the digestibility of dry matter and the concentration of rumen ammonia nitrogen, but does not change the intake of nutritional components, the blood parameters, or the feeding behavior of sheep.

Effects of substituting corn with steam-flaked sorghum on growth, digestion and blood metabolites in young cattle fed feedlot diets

The objective of the present study was to evaluate the effects of substituting ground corn grain with steam-flaked sorghum (SFS) grain on growth performance, nutrient utilisation and blood metabolites in beef bulls. Fifty-six Simmental beef bulls averaging 12 months of age and 356.4 ± 2.6 kg of bodyweight were randomly assigned to four groups. The treatments were control, low-SFS, medium-SFS and high–SFS, with 0, 1/3, 2/3 and 3/3 SFS grain, respectively, substituting ground corn grain of diets(dry matter (DM) basis). Diets consisted of 50% corn silage and 50% concentrate (DM basis). The average daily gain and feed conversion rate improved quadratically with increasing the proportion of SFS grain. Ruminal pH and ammonia-nitrogen (N) concentration decreased quadratically, whereas ruminal total volatile fatty acid concentration increased quadratically. Ratio of acetate to propionate decreased quadratically (P = 0.027) due to the quadratic decrease in acetate production and the quadratic increase in propionate production. Digestibilities of DM, organic matter and crude protein increased quadratically, whereas that of neutral detergent fibre and acid detergent fibre decreased quadratically. The digestible N, retention N and the retention N to digestible N ratio improved quadratically. Inclusion of SFS grain in diets quadratically increased blood concentrations of glucose, total protein, albumin and triglyceride, but quadratically decreased the concentration of urea N. The results indicated that partly substituting ground corn grain with SFS grain could improve growth performance by improving ruminal fermentation and N utilisation; the optimum substitution rate was 2/3 (DM basis).

Effect of dietary starch level and its rumen degradability on lamb meat fatty acid composition

Forty lambs were fed one of four diets supplemented with a linseed and sunflower oil blend but differing in starch level (mid, ≈35 vs. high, ≈50%) and starch rumen degradability (mid, ≈70 vs. high, ≈80%). The effects of diet on growth, carcass traits and meat fatty acid (FA) composition, with emphasis on biohydrogenation intermediates were evaluated. Lambs stayed on trial for 5weeks until slaughter. Treatment had no effect on animal performance and carcass traits. High-degradability diets decreased (P=0.04) meat shear force compared with mid-degradability diets. Lipid content of meat was unaffected by the diet. Mid-starch diets increased (P<0.05) the saturated FA and cis-MUFA but decreased (P<0.05) the trans-MUFA, particularly the t10-18:1, when compared with high-starch diets. The t11-18:1 (0.7% of total FA) and c9,t11-18:2 (<0.3%) remained low and the 18:3n-3 remained high (1.74%) and unaffected by diet.

Evaluation of bovine rumen contents as a feed for lambs

This study evaluated effects of increasing levels of dried rumen contents (DRC) on voluntary intake, growth performance, digestibility, nutritive value, N utilization, microbial protein supply (MPS), and purine derivatives excretion (PDE) of lambs fed with Afzelia africana basal forage. Sixteen lambs (13.7 ± 0.1 kg body weight (BW)) were randomly assigned to one of the four eight diets containing 0, 200, 400 and 600 g DRC/kg dry matter (DM) in a completely random design. Intakes of concentrate, DM, crude protein (CP), organic matter (OM), digestible CP (DCP), digestible OM (DOM), digestible energy (DE) and metabolizable energy (ME), CP and OM digestibility, DOM, DCP, DE, ME, N intake and retention, weight gain, cost/kg BW gain, MPS and PDE increased with increasing DRC level up to 400 g/kg DRC and declined at 600 g/kg DRC (P < 0.05; 0.01). Feed conversion ratio and DM digestibility declined as DRC level increased from 0 to 400 g/kg and peaked at 600 g/kg DRC (P < 0.05; 0.01). Forage intake and DE/DCP ratio decreased (P < 0.05; 0.01) progressively with increasing DRC level. Results indicate that DRC can be incorporated up to 400 g/kg in a compounded ration for sheep.

Assessment of different levels of enset (Ensete ventricosum) corm as an energy supplement in sheep fed a basal diet of Rhodes grass hay

The objective of this experiment was to evaluate the effect of feeding different levels of enset corm as a supplement to sheep fed Rhodes grass hay. Thirty local yearling rams with a mean (±SD) body weight of 16.97 (±1.13) kg were used. Six sheep were allocated to each of the five treatments in a completely randomized design. The treatments were hay ad libitum and 129 g dry matter (DM) corm (T1), 188 g DM corm (T2), 248 g DM corm (T3), 100 g DM noug (T4) cake, and hay alone (T5). One hundred grams of noug seedcake was supplemented for all treatments except T5. Total DM and organic matter (OM) intakes of sheep in T1, T2, and T3 were the highest (P < 0.05) compared with sheep in other treatments, while sheep in T5 consumed the lowest DM and OM. The total crude protein (CP) intakes of sheep in T3 and T2 were greater (P < 0.05) than the other treatments, while sheep in T5 consumed the lowest CP. The apparent DM and OM digestibility coefficients of T1, T2, and T3 diets were higher (P < 0.05) compared with T5. The lowest (P < 0.05) CP digestibility was in T5, whereas the digestibility among the supplemented groups was similar (P > 0.05). The daily body weight gain for T1, T2, and T3 diets was greater (P < 0.05) than that of T5. The feed conversion efficiency for T1 and T2 was higher (P < 0.05) than T5, while T4 had an intermediate value. The highest (P < 0.05) nitrogen retention was in sheep fed T3 diet, while the lowest was in those fed T5. It is concluded that farmers can supplement enset corm at 129 g DM/day as an alternative energy source to improve the productivity of sheep for small-scale farmers under enset-livestock production systems.