Effects of dietary supplementation of postbiotic derived from Bacillus subtilis ACCC 11025 on growth performance, meat yield, meat quality, excreta bacteria, and excreta ammonia emission of broiler chicks

The primary aim of this study was to explore the impact of dietary supplementation with a postbiotic derived from Bacillus subtilis ACCC 11025 on growth performance, meat yield, meat quality, excreta bacterial populations, and excreta ammonia emissions of broiler chicks. A total of 480 day-old Arbor Acre broiler chicks, initially weighing 52.83 ± 1.38 g, were randomly allocated into 4 distinct groups. Each group was housed in 6 separate cages, each containing 20 birds. The experimental phase spanned 42 d, divided into 2 periods (d 1-21 and d 22-42). Dietary interventions were based on a basal diet, with postbiotic supplementation at levels of 0.000, 0.015, 0.030, or 0.045%. Our findings indicate that dietary supplementation with postbiotic had a positive influence on body weight gain (BWG) and feed efficiency. The most substantial improvements in BWG and feed efficiency were observed in the group of broiler chicks fed a diet containing 0.015% postbiotic. Furthermore, the inclusion of postbiotic in the diet led to an increase in the yield of breast and leg muscles, with a significant difference in meat yields observed between the control group and the group receiving 0.015% postbiotic supplementation. It's noteworthy that dietary manipulation did not exert any discernible impact on the quality of breast and leg muscle samples. Concurrently, we observed an elevation in serum albumin and total protein contents corresponding to the increasing postbiotic dosage in the diet. Additionally, dietary supplementation with postbiotic effectively controlled the emission of ammonia from excreta and reduced the abundance of Salmonella in excreta while enhancing the presence of Lactobacillus bacteria. The group receiving 0.015% postbiotic supplementation displayed the lowest levels of ammonia emission and the highest counts of Lactobacillus bacteria in excreta. In light of these results, we conclude that dietary supplementation with 0.015% postbiotic represents an efficacious strategy for increasing BWG and meat yield of broiler chicks by enhancing feed efficiency as well as mitigating ammonia emissions from excreta by modulating the composition of excreta bacterial communities.

Identification of Key Functional Genes and LncRNAs Influencing Muscle Growth and Development in Leizhou Black Goats

Meat yield and quality are important economic traits of livestock. Herein, longissimus dorsi (LD) muscles of Leizhou black goats aged 0, 3, and 6 months were used to identify differentially expressed messenger RNAs (mRNAs) and long non-coding RNAs (lncRNAs) by high-throughput RNA sequencing. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses were used to analyze differentially expressed genes. Expression levels of regulator of calcineurin 1 (RCAN1) and olfactory receptor 2AP1 (OR2AP1) were significantly different in LD muscles of goats aged 0, 3, and 6 months, indicating potentially important roles in postnatal muscle development. Differentially expressed lncRNAs and mRNAs were mainly enriched in biological processes and pathways related to cellular energy metabolism, consistent with previous studies. Three lncRNAs, TCONS_00074191, TCONS_00074190, and TCONS_00078361, may play a cis-acting role with methyltransferase-like 11B (METTL11B) genes and participate in the methylation of goat muscle proteins. Some of the identified genes may provide valuable resources for future studies on postnatal meat development in goat muscles.

Multiple Effects of Egg Weight, in Ovo Carbohydrates, and Sex of Birds on Posthatch Performance in Broilers

Chickens raised for their meat (Gallus gallus domesticus) tend to have a critical phase of life right after hatching due to the management of modern production systems. Early nutrition strategies such as in ovo intervention can be an alternative means to support growth and gut health by compensating for the energy deficit after pipping out of the egg. In the current study, 1200 Ross 308 eggs were used to examine the effects of a complex carbohydrate solution of disaccharides and glucose applied in ovo on hatchability, the hatching time of different-sized eggs, and the development, performance, and carcass characteristics of broilers of both sexes. The eggs were divided into three treatment groups: intact (NT), in ovo saline (ioS), and in ovo carbohydrate mixture (ioCH). The incubation protocol was performed according to the recommendations of Aviagen (2019), and the in ovo process was carried out on day 17 by manually injecting 0.5 mL of the solutions into the amniotic fluid. After hatching, the birds were kept in floor pens until day 35 and fed ad libitum in a three-phase feeding program. Body weight, average daily weight gain, feed intake and conversion, and carcass characteristics were measured during the trial. In ovo carbohydrates reduced hatchability by 15%, while growth performance and the weight of thigh and breast muscle were enhanced significantly (p < 0.05) compared with ioS as a possible outcome of carbohydrate-to-muscle satellite cell proliferation and protein accumulation. However, further study is needed to refine the in ovo carbohydrate supplementation method to minimize the mortality of embryos during hatching.

Effects of Feeding Varying Levels of DL-Methionine on Live Performance and Yield of Broiler Chickens

Simple Summary

The use of DL-methionine (MET) in poultry diet formulation is vital for poultry growth because poultry do not synthesize sufficient amounts of MET needed for proper growth and performance, and currently there are insufficient natural sources of MET to fulfill the dietary needs of broiler chickens. However, the use of MET is restricted in the United States in organic poultry diets. Therefore, the objective of this study was to examine the effect of feeding different levels of dietary MET on organic broiler live performance and yield of a modern commercial broiler strain. This study gives us insight into how broiler growth and yield is affected when the allowable levels of methionine for organic broilers is further reduced, or zero methionine is used.

Abstract

This study was designed to evaluate the effects of dietary supplemental DL-methionine (MET) on live performance and meat yield for broilers raised to a common weight. A total of 1552 one-day old Ross 708, sexed broilers were randomly distributed to 32 pens resulting in eight treatments (TRT) of four replicates with 44 male or 53 female/pen. A randomized complete block with a 2 × 4 (sex × 4 MET levels 0, 0.5, 1, and 2 g/kg) factorial arrangement of TRT was used. A common weight of 2400 g was approached by day 46 (1 and 2 g MET/kg feed) and day 48 (0 and 0.5 g MET/kg feed). Supplementation of MET at 1, and 2 g/kg had a lower (p < 0.01) feed conversion ratio (FCR) at day 46/48 than broilers fed 0.5 g MET/kg. Broilers without supplemental MET had the worst (p < 0.01) feed conversion and average daily gain (ADG) at day 46/48. Birds fed 0 g MET/kg of feed had lower (p < 0.05) whole eviscerated carcass without giblets (WOG), yield than birds fed 2 g MET/kg of feed. Additionally, birds fed 0 g MET/kg of feed had lower (p < 0.05) breast fillet and tender percent yields than birds fed supplemental MET. Elimination of MET from organic broiler diets resulted in reduced ADG, breast fillet yield and feed efficiency of meat yield of broilers raised to day 46/48. Reduction in MET supplementation below current levels reduced the efficiency of meat production of organic broilers raised to day 46/48.

In pursuit of a better broiler: carcass traits and muscle myopathies in conventional and slower-growing strains of broiler chickens

Selection for accelerated growth rate and high breast yield in broiler chickens have been associated with an increase in myopathies, including wooden breast (WB) and white striping (WS). To investigate effects of growth rate on carcass traits and incidence of myopathies, 14 strains were evaluated, encompassing 2 conventional (CONV; strains B and C: ADG0-48 > 60 g/d) and 12 slower-growing (SL) strains. The latter were categorized based on growth rate: FAST (strains F, G, I and M; ADG0-62=53-55 g/d), MOD (strains E, H, O and S; ADG0-62=50-51 g/d), and SLOW (strains D, J, K and N; ADG0-62<50 g/d). In a randomized incomplete block design, 7,216 mixed-sex birds were equally allocated into 164 pens (44 birds/pen; 30 kg/m2), with each strain represented in 8 to 12 pens over 2 to 3 production cycles. From each pen, 4 males and 4 females were processed at 2 Target Weights (TWs) based on their expected time to reach 2.1 kg BW (TW 1: 34 d for CONV; 48 d for SL strains) and 3.2 kg BW (TW 2: 48 d for CONV; 62 d for SL strains). Weights and yields for the carcass, breast, drumsticks, thighs, and wings were obtained; breast fillets were assessed to determine the presence and severity of WB and WS. At both TWs, breast yield was higher as growth rate increased (P < 0.001), with CONV having greater breast yield than other categories. Strain F had the greatest breast yield at both TWs (P < 0.001) within the FAST category. At TW 2, CONV had the greatest incidence of WB and WS (P < 0.001). However, within FAST, strain F had the greatest incidence of myopathies (P < 0.001) at both TWs, exhibiting values as high or as greater than CONV birds. The incidence of WB and WS in strains with differing growth rates but high breast meat yield suggests that the latter may play a major role in the occurrence of these myopathies.

Key Genes Regulating Skeletal Muscle Development and Growth in Farm Animals

Simple Summary

Skeletal muscle mass is an important economic trait, and muscle development and growth is a crucial factor to supply enough meat for human consumption. Thus, understanding (candidate) genes regulating skeletal muscle development is crucial for understanding molecular genetic regulation of muscle growth and can be benefit the meat industry toward the goal of increasing meat yields. During the past years, significant progress has been made for understanding these mechanisms, and thus, we decided to write a comprehensive review covering regulators and (candidate) genes crucial for muscle development and growth in farm animals. Detection of these genes and factors increases our understanding of muscle growth and development and is a great help for breeders to satisfy demands for meat production on a global scale.

Abstract

Farm-animal species play crucial roles in satisfying demands for meat on a global scale, and they are genetically being developed to enhance the efficiency of meat production. In particular, one of the important breeders’ aims is to increase skeletal muscle growth in farm animals. The enhancement of muscle development and growth is crucial to meet consumers’ demands regarding meat quality. Fetal skeletal muscle development involves myogenesis (with myoblast proliferation, differentiation, and fusion), fibrogenesis, and adipogenesis. Typically, myogenesis is regulated by a convoluted network of intrinsic and extrinsic factors monitored by myogenic regulatory factor genes in two or three phases, as well as genes that code for kinases. Marker-assisted selection relies on candidate genes related positively or negatively to muscle development and can be a strong supplement to classical selection strategies in farm animals. This comprehensive review covers important (candidate) genes that regulate muscle development and growth in farm animals (cattle, sheep, chicken, and pig). The identification of these genes is an important step toward the goal of increasing meat yields and improves meat quality.

Sire Effects on Carcass of Beef-Cross-Dairy Cattle: A Case Study in New Zealand

Simple Summary

Cattle born in the dairy industry are a very important source of beef. This study evaluated the carcasses of cattle born to dairy cows and sired by a range of Angus and Hereford sires. Sire affected most carcass traits of their progeny, particularly size and fat traits. The heaviest sire had 46 kg greater carcass weight compared with the lightest sire, equivalent to NZ$266 greater value per progeny. Carcass fat traits (rib fat depth and marble scores) were the most variable among sires, indicating possibility of selection. Thus, using beef-breed sires chosen for greater carcass weight has the potential to increase the meat production of cattle born on dairy farms, while maintaining adequate fat levels and carcass quality to receive optimum payment.

Abstract

There is interest in increasing the carcass value of surplus calves born in the dairy industry that are reared for beef production in New Zealand. This experiment evaluated the carcass of Angus and Hereford sires via progeny testing of beef-cross-dairy offspring grown on hill country pasture. Weight and carcass traits were analyzed from 1015 animals and 1000 carcasses of 73 sires. The mean of the progeny group means was 567 kg for live weight at slaughter, 277 kg for carcass weight, 48.9% for dressing-out, 240.3 cm for carcass length, 73.6 cm² for eye muscle area, 7.4 mm for rib fat depth, 0.91 for marble score, 3.05 for fat color score, 3.01 for meat color score, and 5.62 for ultimate pH. Sire affected (p < 0.05) carcass size and fat traits, but not fat color, meat color, or ultimate pH (p > 0.05). There was a 46 kg increase in carcass weight between the best and worst sires tested. Carcass fat traits were the most variable among sires. The use of genetically superior beef-breed sires over dairy-breed cows has the potential to increase carcass weights from surplus calves born in the dairy industry, while maintaining adequate fat levels and carcass quality.

The Potential of Guanidino Acetic Acid to Reduce the Occurrence and Severity of Broiler Muscle Myopathies

Guanidinoacetic acid (GAA) is the biochemical precursor of creatine, which, in its phosphorylated form, is an essential high-energy carrier in the muscle. Although creatine has limited stability in feed processing, GAA is well established as a source of creatine in the animal feed industry. Published data demonstrate beneficial effects of GAA supplementation on muscle creatine, energy compounds, and antioxidant status, leading to improvements in broiler body weight gain, feed conversion ratio, and breast meat yield. Although increases in weight gain and meat yield are often associated with wooden breast (WB) and other myopathies, recent reports have suggested the potential of GAA supplementation to reduce the occurrence and severity of WB while improving breast meat yield. This disorder increases the hardness of the Pectoralis major muscle and has emerged as a current challenge to the broiler industry worldwide by impacting meat quality. Genetic selection, fast-growth rates, and environmental stressors have been identified to be the main factors related to this myopathy, but the actual cause of this disorder is still unknown. Creatine supplementation has been used as a nutritional prescription in the treatment of several muscular myopathies in humans and other animals. Because GAA is a common feed additive in poultry production, the potential of GAA supplementation to reduce broiler myopathies has been investigated in experimental and commercial scenarios. In addition, a few studies have evaluated the potential of creatine in plasma and blood enzymes related to creatine to be used as potential markers for WB. The evidence indicates that GAA could potentially minimize the incidence of WB. More data are warranted to understand the factors affecting the potential efficacy of GAA to reduce the occurrence and severity of myopathies.

Prediction of the Hind-Leg Muscles Weight of Yearling Dairy-Beef Steers Using Carcass Weight, Wither Height and Ultrasound Carcass Measurements

Simple Summary

Carcass classification and grading systems are typically inadequate for young cattle processed for beef production. Conformation of the hindquarter region of cattle has been used to classify and grade the whole carcass from older beef cattle. This study was initiated with the objective of providing a carcass classification and grading system based on hind-leg muscles weight. Prediction equations for the indirect prediction of saleable meat yield using hind-leg muscles weight from young dairy-origin steers were developed, and could be used for their carcass classification and grading. These equations avoid the need to isolate and track boneless subprimal cuts to establish the saleable meat yield of individual animals.

Abstract

Prediction equations have been widely utilized for carcass classification and grading systems in older beef cattle. However, the equations are mostly relevant for common beef breeds and 18 to 24 month old animals; there are no equations suitable for yearling, dairy-origin cattle. Therefore, this study developed prediction models using 60 dairy-origin, 8 to 12 month old steers to indicate saleable meat yield from hind-legs, which would assist with carcass classification and grading. Fat depth over the rump, rib fat depth, and eye muscle area between the 12th and 13th ribs were measured using ultrasound, and wither height was recorded one week prior to slaughter. The muscles from the hind-leg were retrieved 24 h after slaughter. Prediction equations were modeled for the hind-leg muscles weight using carcass weight, wither height, eye muscle area, rump, and rib fat depths as predictors. Carcass weight explained 61.5% of the variation in hind-leg muscles weight, and eye muscle area explained 39.9% (p < 0.05). Their combination in multivariate analysis explained 63.5% of the variation in hind-leg muscles weight. The R² of the prediction in univariate and multivariate analyses was improved when data were analyzed per age group. Additional explanatory traits for yearling steers, including body length, hearth girth, and muscle depth and dimensions measured using video image analysis scanning (VIAscan), could improve the prediction ability of saleable meat yield from yearling dairy beef steers across the slaughter age groups.

Variation in the Lipin 1 Gene Is Associated with Birth Weight and Selected Carcass Traits in New Zealand Romney Sheep

Lipin 1 plays an important role in lipid metabolism. In this study; we searched for variation in the ovine lipin 1 gene (LPIN1) in three gene regions (a 5' non-coding region; a region containing an alternatively spliced exon in intron 4; and a region containing coding exon 6) using polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP) analysis. The greatest amount of alleles was found in coding exon 6; with five sequences being detected. The effect of variation in this exon was investigated in 242 New Zealand Romney lambs derived from 12 sire-lines. The presence of variant E₃ was associated with a decrease in birth weight (p = 0.005) and the proportion of leg yield (p = 0.045), but with an increase in hot carcass weight (p = 0.032) and the proportion of loin yield (p = 0.014). The presence of variant B₃ was associated with an increased pre-weaning growth rate (p = 0.041), whereas the presence of variant C₃ was associated with an increase in shoulder yield (p < 0.001). These results suggest that ovine LPIN1 variation may have value as a genetic marker for improving meat production and carcass traits.

Comparative effects of inorganic and three forms of organic trace minerals on growth performance, carcass traits, immunity, and profitability of broilers

Objective:

The experiment was conducted to investigate the comparative effects of inorganic trace minerals (ITM) and three forms of organic trace minerals (OTM) (propionate, metho-chelated, and proteinate) on growth performance, edible meat yield, immunity, and profitability of commercial broilers.

Materials and methods:

A corn-soya based mash diet comprising four treatments each of 10 replicates were fed to 720 day-old Cobb 500 broiler chicks for 35 days (starter diet 0–21 days and grower diet 22–35 days). The diets for comparison were as follows: diet 1: control diet with ITM premix at 1 kg/ton of feed (T₁); diet 2: control diet supplemented with propionate trace minerals at 600 gm/ton (T₂); diet 3: control diet supplemented with metho-chelated trace minerals at 500 gm/ton by reducing 225 gm methionine/ton of feed (T₃); and diet 4: control diet supplemented with proteinate trace minerals at 500 gm/ton of feed (T₄). Growth performance, carcass yield, and antibody titer (AT) data were recorded. Data were analyzed and interpreted using SAS Computer Package Program version 9.1.

Results:

Feeding propionate and proteinate OTM showed similar performance. Birds fed these two types (propionate and proteinate) or OTM had better performance in comparison with those receiving ITM and metho-chelated one. Proteinate group produced more wing meat and propionate group showed higher breast and drumstick meat yield as compared with those received the metho-chelated trace mineral and ITM. The birds belonging to OTM groups showed significantly higher AT level against infectious bursal disease. Proteinate minerals groups showed higher profitability followed by propionate fed broilers.

Conclusion:

Two forms of OTM, propionate and proteinate improved performance of commercial broilers over those of ITM and metho-chelated one.

Identification of circulating miRNA involved in meat yield of Korean cattle

Cattle plays an important role in providing essential nutrients through meat production. Thus, we focused on epigenetic factors associated with meat yield. To investigate circulating miRNAs that are involved with meat yield and connect biofluids and longissimus dorsi (LD) muscle in Korean cattle, we performed analyses of the carcass characteristics, miRNA array, qPCR, and bioinformatics. Carcass characteristics relative to the yield grade (YG) showed that the yield index and rib eye area were the highest, whereas the backfat thickness was the lowest for YG A (equal to high YG) cattle among the three YGs. miRNA array sorted the circulating miRNAs that connect biofluids and LD muscle. miRNA qPCR showed that miR-15a (r = 0.84), miR-26b (r = 0.91), and miR-29c (r = 0.92) had positive relationships with biofluids and LD muscle. In YG A cattle, miR-26b was considered to be a circulating miRNA connecting biofluids and LD muscle because the target genes of miR-26b were more involved with myogenesis. Then, miR-26b-targeted genes, DIAPH3 and YOD1, were downregulated in YG A cattle. Our results suggest that miR-15a, miR-26b, and miR-29c are upregulated in biofluids and LD muscle, whereas DIAPH3 and YOD1 are downregulated in the LD muscle of finishing cattle steers.