Carcass Traits, Meat Characteristics, and Economic Viability of Grazing Nellore Cattle Produced Under Different Supplementation Strategies in the Tropics

This study explored the effects of different supplementation strategies in the dry and rainy seasons in the tropics on the carcass traits, meat quality, and economic viability of Nellore cattle produced under grazing conditions. For this purpose, twenty-eight non-castrated male animals (18 months) with an initial body weight of 327.93 ± 4.22 kg were used. The animals were equitably distributed in a randomized complete design thorough four supplementation strategies as follows: i) mineral supplementation (MS) in both dry and rainy seasons (MS/MS), ii) MS in the dry season and concentrate supplementation (CS) in the rainy season (MS/CS), iii) CS in the dry season and MS in the rainy season (CS/MS), and iv) CS in both dry and rainy seasons (CS/CS). Thereafter, carcass traits, primary carcass cut yields, meat quality traits, chemical composition of meat, and economic viability of cattle production across different supplementation strategies were determined. Data revealed that animals under CS/CS showed the greatest (P < 0.01) hot carcass weights among the other supplementation strategies evaluated. Conversely, supplementation strategy did not affect (P > 0.05) carcass traits (the ribeye area, final pH, and forequarter), meat quality traits (shear force, myofibrillar fragment index, sarcomere length, and color), and meat chemical composition (crude protein, fat, and moisture) of the animals. The effective operational cost, total cost, gross revenue, and profit of animals under CS/CS showed the greatest values, whereas the lowest ones were obtained for the animals under MS/MS. In conclusion, data suggest that concentrate supplementation during at least one season (dry or rainy) produces similar meat quality traits and chemical composition of meat, but different hot carcass weight, backfat thickness and hindquarter proportion to those observed when animals were supplemented with concentrate in both seasons. Additionally, CS/CS animals, despite having a higher total cost, have greater profitability when raised in tropical pasture.

Effect of addition cattle feed supplement on in vitro fermentation, synthesis of microbial biomass, and methane production of rice straw fermentation basal diets

The objective of this study was to evaluate the influence of supplementation of cattle feed supplement (CFS) and concentrate in ruminant diets based on rice straw fermented (R) on in vitro rumen fermentation, microbial biomass synthesis, and enteric methane production. Five experimental diets were evaluated, consist of R = rice straw fermented 100%, RS = R + CFS 10%, RSC1, 2 and 3 = RS + Concentrate levels 10, 20 and 30 (%DM). Supplementation of CFS increased the gas production (P < 0.05) and highest in treatments RSC1 and 2 (44.09 and 44.87 ml/g substrate, respectively) and was decreased proportions of methane by inhibition rate until 49.80%. Ruminal protozoa population increased by CFS dan concentrate supplementation (P<0,05) and was dominated (>80%) of Entodinium genus. The treatments RS dan RSC1 promoted greater (P < 0.01) microbial biomass synthesis (386.32 and 312.39 mg/g substrate, respectively). In conclusion, the supplementation of CFS and concentrate in ruminant diets based on rice straw fermented can promote a greater synthesis of microbial biomass and mitigation of methane production.

Dietary Concentrate Supplementation Alters Serum Metabolic Profiles Related to Energy and Amino Acid Metabolism in Grazing Simmental Heifers

Supplementation plays a vital role in the growth performance of grazing heifers. We investigated the effects of maize-based concentrate supplementation on the serum metabolome in grazing heifers. Twenty-four 7-month-old heifers (211.65 ± 4.25 kg BW) were randomly divided into a supplement (SUP) group and a control (CON) group. The results indicated that concentrate supplementation increased the final body weight (BW) of grazing heifers, and the average daily gain (ADG) was 61.5% (P = 0.011) higher in the SUP group than in the CON group. Serum concentrations of total protein (TP), triglyceride (TG), and leptin were higher in the SUP group than in the CON group (p &lt; 0.05). Supplementation increased serum metabolites and amino acids and markedly altered glucose, lipid, and protein metabolism, which contributed to the heifer growth. Furthermore, by multivariate analysis, 45 serum metabolites were identified as significantly different between the two groups. Enrichment analysis revealed that arginine biosynthesis and tryptophan metabolism as well as glycerophospholipid metabolism were significantly enriched between the two groups. We concluded that the growth potential of heifers could be improved by maize-based concentrate supplementation, and the main biological pathways affected were those related to energy and amino acid metabolism.

Effect of high and low energy based concentrate diet supplementation on nutrient intake and body weight changes of buffalo bull calves at Subornochar Upozila of Noakhali district in Bangladesh

This study was designed to investigate the effects of supplementation of high and low energy based concentrate diets (13.77 Vs 12.14 MJ/kg DM metabolizable energy) on the nutrient intake and body weight changes of indigenous growing buffalo bull calves in Bangladesh. The crude protein contents of both the supplemented diets were similar (about 12.50% on DM basis). In this study, a total of fifteen indigenous growing buffalo bull calves (av. Live weight 85.10±0.874 kg) were selected from different villages. It was found that the total dry matter intake was the highest (28.22±0.015 g/kg W0.75/d) in group supplemented with high energy concentrate diet along with farmer’s practices (D1), thereafter, in group supplemented with low energy concentrate diet along with farmer’s practices (D2) (27.79±0.015 g/kg W0.75/d) and the lowest (26.39±0.016 g/kg W0.75/d) in control group (D0) in which the animals were fed only farmers practices diet. Similarly, the crude protein intake was the highest in D1 group (2.86 ±0.029 g/kg W0.75/d), followed by D2 group (2.83±0.010 g/kg W0.75/d) and the lowest in farmer’s practices diet, D0 (2.08b±0.021 g/kg W0.75/d). However, the final body weight of buffalo bull calves was higher in both groups supplemented with concentrate diets (D1 and D2) compared with control (D0) and differed significantly (p<0.01) while there were no significant differences (p>0.05) found between D1 and D2 where high energy concentrate supplementation group buffalo bull claves, D1 tended to be higher than low energy concentrate supplementation group buffalo bull claves, D2. The highest final (254.6 kg) body weight was recorded in high energy concentrate supplemented diets and the lowest (144.0 kg) was found in control. Additionally, the average final body weight was increased by 153.40 kg (151.58%), 150.40 kg (152.22%) and 45.60 kg (46.34%) in D1, D2 and D0 group buffalo bull calves, respectively. On the other hand, the average final body weight of D1 and D2 was increased by 110.60 kg (76.80%) and 105.20 kg (73.05%), respectively, compared with D0. In addition, the highest (6.46) feed conversion efficiency (FCE) was recorded in D1 followed by D2 (6.64) and the lowest (12.17) was found in D0. The trends of cost benefit ratio was the same like other considering factors, the highest (1:3.60) found in D1 followed by D2 (1:3.51) and the lowest (1:1.97) in D0. Finally, considering all the parameters, it was clearly indicated that supplementation of concentrate diet along with farmers practice is essential for fast growing, higher body weight gain and more benefits by rearing buffalo bull calves at Subornochar Upozila of Noakhali district in Bangladesh. Bang. J. Anim. Sci. 2021. 50 (1):50-56

Effect of Post-Grazing Sward Height, Sire Genotype and Indoor Finishing Diet on Steer Intake, Growth and Production in Grass-Based Suckler Weanling-to-Beef Systems

This study evaluated the effects of post-grazing sward height (PGSH, 4 or 6 cm) on herbage production, its nutritive value, dry matter (DM) intake, grazing behaviour and growth of early- (EM) and late-maturing (LM) breed suckler steers (n = 72), and the subsequent effect of indoor finishing diet (grass silage + 3.8 kg concentrate DM/head daily (SC), or grass silage only (SO)) on performance and carcass traits. Animals rotationally grazed pasture for 196 days, followed by indoor finishing for 119 days. At pasture, daily live-weight gain (LWG) was 0.10 kg greater for PGSH-6 than PGSH-4, resulting in a tendency for carcass weight to be 11 kg heavier. Although EM had a 0.10 kg greater daily LWG at pasture than LM, carcass weight did not differ between the genotypes. There was a genotype × PGSH interaction for carcass fat score, whereby there was no difference between EM-4 (8.83, 15-point scale) and EM-6 (8.17), but LM-6 (7.28) was greater than LM-4 (6.33). Although concentrate supplementation during indoor finishing increased carcass weight (+37 kg) and fat score (1.75 units), the majority of steers (83% of EM and 78% of LM) achieved a commercially-acceptable carcass fat score (6.78) at slaughter in the grass-forage-only system.

Expressional Profiling of TEX11, ESRα and BOLL Genes in Yak under Different Feeding Conditions

Previous studies have demonstrated that nutrition plays a crucial part in improving the reproductive potential of farm animals; however, there is currently no research on the transcription and expression profiling of genes in yaks under different feeding conditions. Therefore, this research was planned to compare the transcription and expression profiles of TEX11, ESRα, and BOLL in yaks under natural grazing with concentrate supplementation (NG + CS) and NG without concentrate supplementation. The transcription and expressional levels of TEX11, ESRα, and BOLL mRNA were explored from the testes of yaks using qPCR, Western blotting, immunofluorescence, and immunochemistry. The results of the qPCR illustrated that the transcription levels of TEX11, ESRα, and BOLL were upregulated in the NG + CS group compared to those in the NG group. Moreover, the results of the immunochemistry and immunofluorescence showed that the expression of TEX11, ESRα, and BOLL proteins increased after concentrate supplementation. Meanwhile, ESRα protein levels were lower in the testes and epididymides of yaks in the NG group than in those in the NG + CS group. Similarly, BOLL protein expression was higher in the testes and epididymides of the NG + CS group, but its expression was lower in the epididymides of the NG group. Furthermore, Western blotting showed that the molecular weights of ESRα and BOLL proteins were 64 kDa and 31 kDa, respectively. Finally, in the conclusion we summarize how a proper level of dietary energy supplementation can improve the reproductive potential of yaks by upregulating genes related to reproduction.

Manejo nutricional de novillos criados en pastoreo y en corral: efectos en el consumo, digestibilidad, rendimiento y viabilidad económica

This study aimed to evaluate nutrient intake and digestibility, performance and economic viability of steers during the rearing phase in Brachiaria brizantha cultivar Marandu graze and in feedlot. Were used fifty crossbred steers in the rearing phase, with a mean weight of 275 ± 8.18 kg, distributed in a completely randomized design with ten replications per treatments: Mineral supplementation, nitrogen supplementation, Concentrate supplementation in the order of 1 and 2 g/kg body weight and total feedlot. The total dry matter intake and body weight showed a difference (P<0.05) for animals in feedlot. Crude protein, ether extract, neutral detergent fiber corrected for ashes and protein, non-fibrous carbohydrates, total digestible nutrients showed differences for the animals that received mineral supplementation in comparison to the other managements adopted. The same performance was observed for animals in feedlot. The digestibility coefficients of dry matter, crude protein, ether extract, non-fibrous carbohydrates and total digestible nutrients showed a difference (P<0.05) for the animals that received mineral supplementation, in comparison to the other managements adopted. (P<0.05). The mean daily gain was lower (P<0.05) for animals receiving mineral supplementation. The gross margin was higher (P<0.05) for animals handled in feedlot. Considering the obtained results, it was possible to observe that the animals kept in graze with good availability of dry matter presented satisfactory performance. It is feasible to confine the animals in rearing, since it shortens the production cycle, generating favorable economic results.

Influence of energy supplementation on associative effects in Nellore bulls on a tropical pasture during the rainy season

The objective of this study was to evaluate the influence of energy supplementation on associative effects between forage and concentrate supplements and on the performance of beef cattle on a tropical pasture during the rainy season. Twenty-eight Nellore bulls averaging 19 months of age and 325.2 ± 4.1 kg were allotted to a completely randomized design and distributed into four paddocks of two hectares each with a tropical pasture for 84 d. The treatments consisted of bulls on Urochloa brizantha cv. Xaraés pasture without concentrate supplementation or bulls on Urochloa brizantha cv. Xaraés pasture receiving concentrate supplementation at 15 (S15), 30 (S30) or 45% (S45) of the total digestible nutrients (TDN) requirement All bulls had ad libitum access to mineral supplementation. The amount and chemical composition of the supplement were adjusted every 28 d. Forage and supplement intakes were evaluated in all animals using fecal markers. Crude protein: digestible organic matter ratio decreased with supplementation; consequently, the imbalance between dietary protein and energy increased. Forage intake decreased with increasing supplementation. The substitution rates of pasture for supplementary feed were 0.14, 0.33, and 0.46 for bulls from S15, S30, and S45 treatments, respectively. However, the apparent DM digestibility increased linearly with supplementation level. Supplementation improved the assimilation of ammonia-N in the rumen. Energy supplementation for Nellore bulls on tropical pastures during the rainy season provides excess energy relative to protein, resulting in a substitution effect of supplement intake on forage intake. Moreover, energy supplementation does not improve body weight gain. Protein sources should be added to supplements for balancing protein and energy levels, thereby reducing a likely substitution effect.