Eye Muscle Area Research Articles

Wagyu Feeder Check: A genomic-based tool to identify performance differences of Australian Wagyu and Wagyu crossed cattle

Context Wagyu Feeder Check is a genomic-based tool designed to provide genomic estimated breeding values (GEBV) for five feedlot growth and carcase traits. At present, Wagyu Feeder Check is based on a reference population of 8316 genotyped and phenotyped Australian fullblood (FB; N = 2120) Wagyu and Wagyu-crossed (XB; N = 6196) cattle, principally Wagyu × Angus F1 animals. Aims We provide technical details behind the development of the Wagyu Feeder Check and validate the ability of its GEBV to predict differences in performance of Wagyu cattle in daily weight gain at feedlot, carcase weight, carcase eye muscle area, carcase marbling score and carcase rump fat at the P8 site. Methods Data supplied from eight commercial supply chains across Australia was used to generate GEBV using mixed-model equations that incorporated a genomic relationship matrix build with 82 504 autosomal markers. The bias, dispersion, and accuracy of the GEBV were evaluated using a four-way cross-validation scheme where, in each turn, the phenotypes from a random 1549 (or 25%) XB cattle were set as missing. Key results The genomic estimate of the Wagyu content in the FB and XB population averaged 99.12% and 59.55%, respectively, and with most of the non-Wagyu content associated with Angus. The estimates of heritability (± s.e.) were 0.497 ± 0.016, 0.474 ± 0.004, 0.347 ± 0.014, 0.429 ± 0.003 and 0.422 ± 0.003 for daily weight gain at feedlot, carcase weight, eye muscle area, marbling and rump fat, respectively. Averaged across the four XB validation populations, the accuracy of GEBV was 0.624, 0.634, 0.385, 0.620, and 0.526 for the same set of traits. Conclusions Genomic predictions generated by Wagyu Feeder Check can predict differences in feedlot and carcase performance of Australian Wagyu cattle. Given the large content of Angus in the XB population, further research is required to determine the predictive ability of GEBV in Wagyu × Bos indicus and Wagyu × dairy animals. Implications Commercial feedlot operators finishing animals with a strong Wagyu breed component will benefit from using Wagyu Feeder Check for decision making.

PSXII-20 Differences in Fat Accretion Rate of Different Depots of Angus, Brahman and Charolais Feedlot Steers

Abstract Understanding accretion rate of intramuscular and subcutaneous fat in feedlot steers is crucial to ensure that carcasses are meeting market specifications and therefore optimizing profitability. Intramuscular fat (marbling) and subcutaneous fat (P8 and rib) are key areas of assessment on the live animals and carcasses determining quality. The objective of the present study was to determine fat accretion rate in three popular breeds of cattle with contrasting accretion rate throughout the feedlotting period. We hypothesized that Angus would have the fastest fat accretion rate being early maturing. Thirty of each Angus, Brahman and Charolais steers were entered into a feedlot (344 ± 5.3 kg initial BW) and six of each breed randomly selected for slaughter at 50-day intervals for 200 days on feed (DOF). Ultrasound scanning and BW were measured at each slaughter point, measuring fat thickness at the rib and P8 site, intramuscular fat (IMF), kidney fat and the eye muscle area (EMA). Body weight, intramuscular fat (%), P8 and rib fat (mm) all had significant interactions between DOF and breed (P < 0.001). At the start of the feeding period, Charolais were lighter than Angus and Brahman (P > 0.001). However, Charolais (663.7 ± 9.31 kg) and Angus were the heavier (680.4 ± 8.68 kg) than Brahman (539.4 ± 8.68 kg) at 200 DOF (P < 0.05). The interaction for P8 and rib fat was due to all breeds having similar fat thickness at 0 DOF (P > 0.05) but Angus had greatest (21.38 ± 0.882 mm, 17.12 ± 0.549 mm), Brahman intermediate (16.73 ± 0.883 mm and 10.38 ± 0.550 mm) and Charolais thinnest (9.97 ± 0.966 mm, 7.23 ± 0.600 mm) P8 and rib fat, respectively, at 200 DOF (P < 0.05). Similarly, IMF was similar between breeds at 0 DOF (P > 0.05), but Angus had greater IMF (7.76 ± 0.287 %; P < 0.001) compared with Brahman (5.08 ± 0.287 %) and Charolais (5.18 ± 0.314 %), which were not different amongst them (P > 0.10). Results of the present study demonstrated the contrasting fat metabolisms of each genotype with Angus steers showing the fastest fat accretion rate for all fat depots, whereas Brahman steers showed intermediate and Charolais slowest subcutaneous fat accretion rate. However, both Brahman and Charolais steers showed similarly low IMF and kidney fat accretion rates. Fat accretion rate of each depot and whole body should be considered in mathematical simulation models of animal growth.

Variation in Acetyl-CoA Carboxylase Beta Gene and Its Effect on Carcass and Meat Traits in Gannan Yaks.

Acetyl-CoA carboxylase beta (ACACB) is a functional candidate gene that impacts fat deposition. In the present study, we sequenced exon 37-intron 37, exon 46-intron 46, and intron 47 of yak ACACB using hybrid pool sequencing to search for variants and genotyped the gene in 593 Gannan yaks via Kompetitive allele-specific polymerase chain (KASP) reaction to determine the effect of ACACB variants on carcass and meat quality traits. Seven single nucleotide polymorphisms were detected in three regions. Eight effective haplotypes and ten diplotypes were constructed. Among them, a missense variation g.50421 A > G was identified in exon 37 of ACACB, resulting in an amino acid shift from serine to glycine. Correlation analysis revealed that this variation was associated with the cooking loss rate and yak carcass weight (p = 0.024 and 0.012, respectively). The presence of haplotypes H5 and H6 decreased Warner-Bratzler shear force (p = 0.049 and 0.006, respectively), whereas that of haplotypes H3 and H4 increased cooking loss rate and eye muscle area (p = 0.004 and 0.034, respectively). Moreover, the presence of haplotype H8 decreased the drip loss rate (p = 0.019). The presence of one and two copies of haplotypes H1 and H8 decreased the drip loss rate (p = 0.028 and 0.004, respectively). However, haplotype H1 did not decrease hot carcass weight (p = 0.011), whereas H3 increased the cooking loss rate (p = 0.007). The presence of one and two copies of haplotype H6 decreased Warner-Bratzler shear force (p = 0.014). The findings of the present study suggest that genetic variations in ACACB can be a preferable biomarker for improving yak meat quality.

Effects of fermented bamboo powder on growth performance, apparent digestibility, carcass traits, and meat quality in growing-finishing pigs

The purpose of this experiment is to study the effects of fermented bamboo powder (FBP) on growth performance, apparent digestibility, carcass traits, and meat quality in growing-finishing pigs. A total of 72 barrows (initial body weight, 90.37 ± 0.73 kg) were randomly allocated to 4 dietary treatments in a 42 d trial, including a control (CON) diet and 3 FBP supplementation diets. In this experiment, the CON group was fed the basic diet, whereas, in the FBP group, wheat bran was replaced with different proportions of FBP, which were 2.5 % (FBP 2.5 %), 5.0 % (FBP 5 %), 10.0 % (FBP 10 %), respectively. The results showed that FBP of 2.5 % and 5 % had no negative effect on the performance of growing-finishing pigs (P > 0.05), FBP could increase the digestibility of feed, decrease the average backfat thickness, increase the loin eye muscle area, and make the meat color fresher (P < 0.05), more in line with Chinese consumers' buying habits. Adding 10 % FBP increased the feed-to-gain ratio; increased water holding capacity and drip loss of pork (P < 0.05) and decreased the content of intermuscular fat of pork (P < 0.05), thus decreasing the taste of pork. To sum up, FBP can be used as a feed raw material to replace part of the grain, and the recommended addition ratio is 5 %.

Contribution analysis of carcass traits on auction price for Hanwoo steers in the Yeongnam region of Korea

In this study, Data were the carcass grade on each 53,829 head of hanwoo steers slaughtered 3 years before (2017, 2018, 2019), 32,910 head of hanwoo steers slaughtered after (2020, 2021, 2022) COVID-19 at Yeongnam region and 54,369 head of hanwoo steers slaughtered same period at except for Yeongnam region. To find out the contribution of carcass traits to auction price and total price were analyzed through regression coefficients by using multiple regression analysis. As environmental factors affecting these carcass traits, slaughter year and slaughter season were set and analyzed through the least square method. The results of slaughter year showed that the grade of carcass traits in Yeongnam region increased over the years. In addition, in the slaughter season, the grade of carcass traits in the fall was found to be excellent. According to the contribution analysis, the results of the contribution ratio to auction price of before and after COVID-19 in Yeongnam region and after COVID-19 in all regions except Yeongnam were the same in order of marbling score, backfat thickness, eye muscle area, carcass weight. Also, the contribution ratio to total price were the same in order of carcass weight, marbling score, backfat thickness, eye muscle area. The general carcass grade is intended to use and analyze data from Yeongnam region, which has excellent backfat thickness and carcass weight, also has the largest number of elite cows selected through the verification work of elite cow by Korea Animal Improvement Association, and use it as a means for strategies to increase farm’s income and advance to high quality about Korean beef.

Analysis of environmental effects and estimation of genetic parameters for carcass traits in Hanwoo steers produced through embryo transfer

This study estimated the environmental effects and genetic parameters for carcass traits of 2,309 Hanwoo steers produced through Embryo Transfer (ET) to confirm the performance improvement achieved. The data used for analysis collected information on offspring produced by ET from 2012 to 2020. SAS 9.4 GLM package was used to analyze the environmental effects affecting carcass traits, and genetic parameters were estimated using the REMLF90 program for heritability, genetic correlation, and phenotypic correlation. The collected Carcass Weight (CWT), Eye Muscle Area (EMA), Back-Fat Thickness (BFT), and Marbling Score (MS) were 505.2±58.19kg, 105.57±13.41cm2, 12.76±4.27mm, and 7.25±1.61 points, respectively. It was found that the environmental effect of growth area and slaughter month had a significant effect (p&lt;0.01) on carcass traits. Heritability was 0.51, 0.64, 0.36, and 0.59 in CWT, EMA, BFT, and MS, respectively, and high heritability was observed in all traits except BFT. Due to the characteristics of ET, it is considered that the effect of genetic improvement was more pronounced because there were many offspring with the same parents or the same father or mother. Therefore, it is judged that more efficient improvement effect and performance can be confirmed if an optimal environmental model is set based on the results of this study and used as basic data for breeding. If these results continue to accumulate, it is thought that it will be able to contribute to the increase in farm household income through the improvement effect.

Short-term dietary choline supplementation alters the gut microbiota and liver metabolism of finishing pigs.

Choline is an essential nutrient for pig development and plays a role in the animal's growth performance, carcass characteristics, and reproduction aspects in weaned pigs and sows. However, the effect of choline on finishing pigs and its potential regulatory mechanism remains unclear. Here, we feed finishing pigs with 1% of the hydrochloride salt of choline, such as choline chloride (CHC), under a basic diet condition for a short period of time (14 days). A 14-day supplementation of CHC significantly increased final weight and carcass weight while having no effect on carcass length, average backfat, or eye muscle area compared with control pigs. Mechanically, CHC resulted in a significant alteration of gut microbiota composition in finishing pigs and a remarkably increased relative abundance of bacteria contributing to growth performance and health, including Prevotella, Ruminococcaceae, and Eubacterium. In addition, untargeted metabolomics analysis identified 84 differently abundant metabolites in the liver between CHC pigs and control pigs, of which most metabolites were mainly enriched in signaling pathways related to the improvement of growth, development, and health. Notably, there was no significant difference in the ability of oxidative stress resistance between the two groups, although increased bacteria and metabolites keeping balance in reactive oxygen species showed in finishing pigs after CHC supplementation. Taken together, our results suggest that a short-term supplementation of CHC contributes to increased body weight gain and carcass weight of finishing pigs, which may be involved in the regulation of gut microbiota and alterations of liver metabolism, providing new insights into the potential of choline-mediated gut microbiota/metabolites in improving growth performance, carcass characteristics, and health.

Identification of Missense Variants Affecting Carcass Traits for Hanwoo Precision Breeding.

This study aimed to identify causal variants associated with important carcass traits such as weight and meat quality in Hanwoo cattle. We analyzed missense mutations extracted from imputed sequence data (ARS-UCD1.2) and performed an exon-specific association test on the carcass traits of 16,970 commercial Hanwoo. We found 33, 2, 1, and 3 significant SNPs associated with carcass weight (CW), backfat thickness (BFT), eye muscle area (EMA), and marbling score (MS), respectively. In CW and EMA, the most significant missense SNP was identified at 19,524,263 on BTA14 and involved the PRKDC. A missense SNP in the ZFAND2B, located at 107,160,304 on BTA2 was identified as being involved in BFT. For MS, missense SNP in the ACVR2B gene, located at 11,849,704 in BTA22 was identified as the most significant marker. The contribution of the most significant missense SNPs to genetic variance was confirmed to be 8.47%, 2.08%, 1.73%, and 1.19% in CW, BFT, EMA, and MS, respectively. We generated favorable and unfavorable haplotype combinations based on the significant SNPs for CW. Significant differences in GEBV (Genomic Estimated Breeding Values) were observed between groups with each favorable and unfavorable haplotype combination. In particular, the missense SNPs in PRKDC, MRPL9, and ANKFN1 appear to significantly affect the protein's function and structure, making them strong candidates as causal mutations. These missense SNPs have the potential to serve as valuable markers for improving carcass traits in Hanwoo commercial farms.

Metabolomics Analysis Provides Novel Insights into the Difference in Meat Quality between Different Pig Breeds.

The Chuanzang black (CB) pig is a new crossbred between Chinese local breeds and modern breeds. Here, we investigated the growth performance, plasma indexes, carcass traits, and meat quality characteristics of conventional DLY (Duroc × Landrace × Yorkshire) crossbreed and CB pigs. The LC-MS/MS-based metabolomics of pork from DLY and CB pigs, as well as the relationship between the changes in the metabolic spectrum and meat quality, were analyzed. In this study, CB pigs presented lower final body weight, average daily gain, carcass weight, and eye muscle area than DLY pigs (p ˂ 0.05). Conversely, the ratio of feed to gain, marbling score, and meat color score of longissimus dorsi (LD) were higher in CB than DLY pigs (p ˂ 0.05). Moreover, psoas major (PM) showed a higher meat color score and a lower cooking loss in CB than DLY pigs (p ˂ 0.05). Interestingly, CB pigs showed lower myofiber diameter and area but higher myofiber density than DLY pigs (p ˂ 0.05). Furthermore, the mRNA expression levels of MyHC I, PPARδ, MEF2C, NFATC1, and AMPKα1 were higher in CB than DLY pigs (p ˂ 0.05). Importantly, a total of 753 metabolites were detected in the two tissues (e.g., psoas major and longissimus dorsi) of CB and DLY pigs, of which the difference in metabolite profiles in psoas major between crossbreeds was greater than that in longissimus dorsi. Specifically, palmitic acid, stearic acid, L-aspartic acid, corticosterone, and tetrahydrocorticosterone were the most relevant metabolites of psoas major meat quality, and tetrahydrocorticosterone, L-Palmitoylcarnitine, arachidic acid, erucic acid, and 13Z,16Z-docosadienoic acid in longissimus dorsi meat were positively correlated with meat quality. The most significantly enriched KEGG pathways in psoas major and longissimus dorsi pork were galactose metabolism and purine metabolism, respectively. These results not only indicated improved meat quality in CB pigs as compared to DLY pigs but may also assist in rational target selection for nutritional intervention or genetic breeding in the swine industry.

Direct – Maternal Genetic Parameters Estimated for Real-Time Ultrasound Scan Measures of Eye Muscle Area, Rib Fat Depth, and their Correlation with Body Weight in Male Philippine Riverine Buffaloes

Background: Ultrasound scanning is a non-invasive technique for evaluating animals based on carcass yield and meat quality traits. It has been incorporated into the beef cattle breeding program. However, little has been done in buffaloes. Thus, this study was conducted to estimate the genetic parameters for growth traits- body weights (BW) and a real-time ultrasound scan of eye muscle area (EMA) and rib fat (RF) to determine their suitability as a tool for selection.&#x0D; Methods: Four hundred thirty-eight (438) male Philippine riverine buffaloes with 1,535 BW records and 417 real-time ultrasound scans of EMA and RF scans at the 12th rib were available for the study. BW was taken and adjusted at birth, 6, 12, 18, 24, 30, and 36 months while RF and EMA scans were taken at 12 &amp; 18 mos. Genetic parameters were estimated with a pedigree-based multi-trait animal model using ASREML software.&#x0D; Results: The average BW of buffaloes adjusted to 6, 12, 18, 24, 30, and 36 months of age were 135kg, 230.8kg, 323.0kg, 382.7, 453.6, and 502.4kg, respectively. The mean EMA and RF at 12 months were 29.7 cm2 and 3.2mm, respectively. Direct genetic heritabilities were 0.26±0.16, 0.29±0.12, 0.35±0.19 and 0.67±0.32 for birth, BW12mos, EMA12mos and RF12mos, respectively. Maternal genetic heritability for birth weight. was 0.12±0.09. Genetic correlations among traits were positive except between birth and RF.&#x0D; Conclusions: Results indicate that ultrasound scanning can be used for selection together with BW at 12mos. and suggest that early performance is an excellent predictor of performance at a later age.

Performances, carcass characteristics, and economic benefit of yearling Hararghe highland rams fed diet containing concentrate mixtures and sugarcane bagasse or rice husk treated with Trichoderma viride and effective microorganisms.

The productivity of small ruminants in Ethiopia is low due to a shortage of feed supply throughout the year, both in terms of quality and quantity. This problem leads to the utilization of locally available lignocellulose by-products, which encompass high cellulose, hemicellulose, and lignin. It is known that the nutritive value of these lignocellulose by-products can be improved through biological, chemical, or a combination of both treatments This study was aimed at evaluating body weight change, carcass characteristics, and economic efficiency of rams fed a total mixed diet containing biologically treated rice husk (RH) or sugarcane bagasse (SCB). Thirty-six sheep, weighing an average initial body weight of 18 ± 1.8 kg were used. Two feeds (SCB and RH) and three biological treatments (Control, Trichoderma viride [Tv], and effective microbes [EM]) were used with a randomized complete block design (RCBD) in 2 × 3 factorial arrangements. Ram fed on RH containing diets had higher dry matter intake (DMI) (g/h/day), DMI (% of BW), DMI (g/kg BW0.75), average daily gain (ADG) (106 vs. 53 g/day), and feed conversion efficiency (FCE) (0.107 vs. 0.076) than SCB containing diets. Ram fed diets containing biologically treated roughages had significantly higher (p < .05) DMI (g/h/day), DMI (% of BW), DMI (g/kg BW0.75), ADG, and FCE. However, no significant differences were observed between sheep fed diets containing EM and Tv in DMI (g/h/day), DMI (% of BW), DMI (g/kg BW0.75), ADG, and FCE. This study also revealed that significantly (p < .05) higher carcass weight, dressing percentage (DP), rib eye muscle area, total non-carcass fat, and total edible offal components had been recorded for rams fed diets containing RH as roughage source related to rams fed diets containing SCB. While other parameters were unaffected by treatments, sheep fed diets containing biologically treated feed had a higher hot carcass weight plus DP. However, no significant (p > .05) difference was found between diets based on biologically treated roughage. Profitability analysis indicated that sheep fattening on a diet containing RH and by-products treated with Tv and EM showed greater profitability than untreated SCB. The authors had concluded that fattening sheep on diets containing RH results in higher feed intake, better body weight gain, more carcasses and higher profits, but optimum inclusion levels need further research, for either treated or untreated SCB.

A Comparative Study on the Growth Performance and Gut Microbial Composition of Duroc and Yorkshire Boars.

The intestinal microbiota is required for maintaining the development and health of the host. However, the gut microbiota contributing to the regulation of the growth performance and health of Duroc and Yorkshire boars remains largely unknown. In this study, we first evaluated the difference in the growth performance between Duroc and Yorkshire boars when their body weight reached 100 kg. Relative to Duroc boars, Yorkshire boars weighed 100 kg at a younger age and exhibited a significantly lower backfat thickness and eye muscle area. Microbial analysis of the fecal samples revealed a marked difference in gut microbiota composition between the two pig models and remarkably increased α-diversity in Yorkshire boars compared to Duroc boars. Further analysis indicated that Bacteroidota, Prevotellaceae, and Ruminococcaceae might be associated with the growth performance and lean meat rate of Yorkshire boars. Taken together, these results highlight that Yorkshire boars exhibit a faster growth rate and higher lean meat rate compared to Duroc boars, and these differences may be attributed to the influence of the gut microbiota, thereby providing valuable insight into optimizing pig breeding systems and selecting terminal paternal sires to enhance overall productivity and quality.

Genome-Wide Association Study to Identify QTL for Carcass Traits in Korean Hanwoo Cattle.

This study aimed to identify genetic associations with carcass traits in Hanwoo cattle using a genome-wide association study. A total of 9302 phenotypes were analyzed, and all animals were genotyped using the Illumina Bovine 50K v.3 SNP chip. Heritabilities for carcass weight (CWT), eye muscle area (EMA), backfat thickness (BF), and marbling score (MS) were estimated as 0.42, 0.36, 0.36, and 0.47, respectively, using the GBLUP model, and 0.47, 0.37, 0.36, and 0.42, respectively, using the Bayes B model. We identified 129 common SNPs using DGEBV and 118 common SNPs using GEBV on BTA6, BTA13, and BTA14, suggesting their potential association with the traits of interest. No common SNPs were found between the GBLUP and Bayes B methods when using residuals as a response variable in GWAS. The most promising candidate genes for CWT included SLIT2, PACRGL, KCNIP4, RP1, XKR4, LYN, RPS20, MOS, FAM110B, UBXN2B, CYP7A1, SDCBP, NSMAF, TOX, CA8, LAP3, FAM184B, and NCAPG. For EMA, the genes IBSP, LAP3, FAM184B, LCORL, NCAPG, SLC30A9, and BEND4 demonstrated significance. Similarly, CYP7B1, ARMC1, PDE7A, and CRH were associated with BF, while CTSZ, GNAS, VAPB, and RAB22A were associated with MS. This finding offers valuable insights into genomic regions and molecular mechanisms influencing Hanwoo carcass traits, aiding efficient breeding strategies.

Effect of dietary arginine supplementation on protein synthesis, meat quality and flavor in growing lambs

This study aimed to assess the effect of dietary arginine supplementation on protein synthesis, meat quality and flavor in lambs. Eighteen Dorper (♂) × Small Tailed Han sheep (♀) crossed ewe lambs of similar weight (27.29 ± 2.02 kg; aged 3 months) were assigned to two groups, the control group was fed the basal diet (Con group), and the arginine group (Arg group) was supplemented with 1% l-arginine based on the Con group for 90 d. The results suggested that dietary arginine significantly increased final body weight, loin eye muscle area, muscle fiber diameter, cross-sectional area (P < 0.050), and decreased shear force value and cooking loss (P < 0.050), as well as altered the composition and contents of volatile flavor compounds in lambs. Importantly, the total protein (TP) content, alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (AKP) activities in serum, branched-chain aminotransferase (BCAT), AST, ALT activities and neuronal nitric oxide synthase (nNOS) gene expression and content were elevated (P < 0.050), while content of urea nitrogen (BUN) in serum and 3-methylhistidine (3-MH) were decreased in arginine fed lambs (P < 0.050). In addition, arginine triggered muscle protein synthesis through protein kinase B (Akt)/mammalian target of rapamycin (mTOR) signaling pathway, while minimized protein degradation by regulating gene expression of myogenin (MyoG), myostatin (MSTN), muscle atrophy F-box (MAFbx) and forkhead box O3 family (FoxO3) (P < 0.050). Taken together, this study suggested that arginine can be used to improve protein deposition and meat quality in lamb production.

Comparison of accuracy of breeding value for cow from three methods in Hanwoo (Korean cattle) population.

In Korea, Korea Proven Bulls (KPN) program has been well-developed. Breeding and evaluation of cows are also an essential factor to increase earnings and genetic gain. This study aimed to evaluate the accuracy of cow breeding value by using three methods (pedigree index [PI], pedigree-based best linear unbiased prediction [PBLUP], and genomic-BLUP [GBLUP]). The reference population (n = 16,971) was used to estimate breeding values for 481 females as a test population. The accuracy of GBLUP was 0.63, 0.66, 0.62 and 0.63 for carcass weight (CWT), eye muscle area (EMA), back-fat thickness (BFT), and marbling score (MS), respectively. As for the PBLUP method, accuracy of prediction was 0.43 for CWT, 0.45 for EMA, 0.43 for MS, and 0.44 for BFT. Accuracy of PI method was the lowest (0.28 to 0.29 for carcass traits). The increase by approximate 20% in accuracy of GBLUP method than other methods could be because genomic information may explain Mendelian sampling error that pedigree information cannot detect. Bias can cause reducing accuracy of estimated breeding value (EBV) for selected animals. Regression coefficient between true breeding value (TBV) and GBLUP EBV, PBLUP EBV, and PI EBV were 0.78, 0.625, and 0.35, respectively for CWT. This showed that genomic EBV (GEBV) is less biased than PBLUP and PI EBV in this study. In addition, number of effective chromosome segments (Me) statistic that indicates the independent loci is one of the important factors affecting the accuracy of BLUP. The correlation between Me and the accuracy of GBLUP is related to the genetic relationship between reference and test population. The correlations between Me and accuracy were -0.74 in CWT, -0.75 in EMA, -0.73 in MS, and -0.75 in BF, which were strongly negative. These results proved that the estimation of genetic ability using genomic data is the most effective, and the smaller the Me, the higher the accuracy of EBV.

Performance, carcass, and meat traits of locally adapted Brazilian cattle breeds under feedlot conditions.

Little is known about the performance, carcass, and meat traits of locally adapted cattle in Brazil. This study aimed to compare the growth, slaughter, and carcass traits as well as meat quality of two local breeds (Curraleiro Pé-Duro and Pantaneiro) with the Nelore breed. Fifteen 30-month-old steers of each breed were weighted (Curraleiro Pé-Duro = 264.80 kg; Nelore = 346.80 kg; Pantaneiro = 316.20 kg) and raised in a feedlot condition for 112 days, with measurements to assess growth and slaughter, visual and carcass and meat traits. Data were submitted to variance and multivariate analyses. Nelore and Curraleiro Pé-Duro had similar Gluteus medius depths. Pantaneiro and Curraleiro Pé-Duro were superior for leg compactness index (P < 0.05) and had higher eye muscle area than Nelore (P < 0.05). Although there was no difference in daily weight gain and slaughter weight between breeds, Curraleiro Pé-Duro had a lower initial weight (264.80 kg) when compared to Nelore (346.80 kg; P < 0.05). Nelore and Curraleiro Pé-Duro deposited more fat than Pantaneiro (P < 0.05), while Curraleiro Pé-Duro and Pantaneiro had more muscle than Nelore (P < 0.05), which also had more bone and a higher percentage of second-quality cuts (P < 0.05). Meat from Nelore also showed lower succulence than Pantaneiro (P < 0.05) and higher shear force than the other breeds (P < 0.05). Pantaneiro's meat had the most capacity to retain water (P < 0.05), lower shear force (P < 0.05), and was more succulent (P < 0.05) when compared to the other breeds. Multivariate analysis showed that Pantaneiro, Curraleiro Pé-Duro, and Nelore breeds can be considered distinct in growth, carcass, and meat traits, with the local breeds showing superior meat traits. The local breeds Curraleiro Pé-Duro and Pantaneiro presented characteristics similar or better to those of the Nelore, proving to be animals with great productive potential and generate high meat quality under feedlot conditions.

Production performance and rumen bacterial community structure of Hu sheep fed fermented spent mushroom substrate from Pleurotus eryngii

This study aimed to investigate the effect of fermented spent mushroom substrate from Pleurotus eryngii (SMPE) supplementation on production performance, meat quality and rumen bacterial community structure of Hu sheep. 120 2-month-old Hu sheep with average body weight [(13.50 ± 3.10) kg] were selected and randomly divided into 4 groups with 3 replicates per group and 10 sheep per replicate. The control group (RL1) was fed a total mixed ration (TMR), and group RL2, RL3 and RL4 were fed the basal diets supplemented with 15%, 30% and 45% fermented SMPE, respectively. The pretest period lasted for 10 days and the test period lasted for 150 days. The results showed that: (1) Difference (p < 0.05) was observed in average daily feed intake (ADFI) and feed conversion ratio (FCR) between RL2 and RL4 groups. The eye muscle area (EMA) and grade rule (GR) values in RL2 and RL3 were significantly higher than those in RL1 and RL4 groups (p < 0.05). (2) The contents of threonine, valerine, leucine, lysine, histidine, essential amino acids, flavor amino acids, aspartic acid, serine, glutamic acid and arginine of the longissimus dorsi muscle in RL2 and RL3 groups were significantly higher than RL1 and RL4 (p < 0.05). (3) A total of 1,202,445 valid sequences were obtained from rumen of Hu sheep fed different amounts of fermented feed, and the valid sequences were clustered into 9824 Operational Taxonomic Units (OTUs). (4) α diversity analysis showed that the richness and diversity of rumen bacterial communities in Hu sheep in RL1, RL2, RL3 and RL4 groups were significantly higher than RL0 (raw materials of fermented SMPE) group (p < 0.05). β diversity analysis showed that the bacterial community structure was the most different between RL0 and RL3. (5) At the genus level, compared with RL1, the relative abundance of Christensenellaceae R-7 in RL3 group decreased significantly by 33.59%, the relative abundance of Prevotellaceae UCG001 in RL2, RL3 and RL4 decreased significantly by 50.41%, 62.24% and 49.17%, respectively, and the relative abundance of Ruminococcaceae NK4A214 in RL2 group increased significantly by 35.01% (p < 0.05). In summary, the addition of fermented SMPE to TMR can significantly improve the production performance, meat quality and rumen bacterial community diversity and abundance of Hu sheep.

Assessment of genomic breeding values and their accuracies for carcass traits in Jeju Black cattle using whole-genome SNP chip panels.

The objective of the present study was to evaluate the breeding value and accuracy of genomic estimated breeding values (GEBVs) of carcass traits in Jeju Black cattle (JBC) using Hanwoo steers and JBC as a reference population using the single-trait animal model. Our research included genotype and phenotype information on 19,154 Hanwoo steers with 1097 JBC acting as the reference population. Likewise, the test population consisted of 418 genotyped JBC individuals with no phenotypic records for those carcass traits. For estimating the accuracy of GEBV, we divided the entire population into three groups. Hanwoo and JBC make up the first group; Hanwoo and JBC, who has both the genotype and phenotypic records, are referred to as the reference (training) population, and JBC, who lacks phenotypic information is referred to as the test (validation) population. The second group consists of the JBC (without phenotype) as the test population and Hanwoo as a reference population with phenotype and genotypic data. The only JBCs in the third group are those who have genotypic and phenotypic data on them as a reference population but no phenotypic data on them as a test population. The single-trait animal model was used in all three groups for statistical purposes. The reference populations estimated heritabilities for carcass weight (CWT), eye muscle area (EMA), backfat thickness (BF), and marbling score (MS) as 0.30, 0.26, 0.26, and 0.34 for the Hanwoo steer and 0.42, 0.27, 0.26, and 0.48 for JBC. The average accuracy for carcass traits in Group 1 was 0.80 for the Hanwoo and JBC reference population compared with 0.73 for the JBC test population. Although the average accuracy for carcass traits in Group 2 was 0.80, it was 0.80 for the Hanwoo reference population and only 0.56 for the JBC test population. The average accuracy for the JBC reference and test populations was 0.68 and 0.50, respectively, when they were included in the accuracy comparison without the Hanwoo reference population. Groups 1 and 2 used Hanwoo as reference population, which led to a better average accuracy; however, Group 3 only used the JBC reference and test population, which led to a lower average accuracy. This might be due to the fact that Group 3 used a smaller reference size than the group that came before it and that the genetic makeup of the Hanwoo and JBC breeds differed. The GEBV accuracy for MS was higher than that of other traits across all three analysis groups, followed by CWT, EMA, and BF, which may be partially explained by the MS traits' higher heritability. This study suggests that in order to achieve more accuracy, a large reference population particular to a breed should be established. Therefore, to increase the accuracy of GEBV prediction and the genetic benefit from genomic selection in JBC, individual reference breeds, and large populations are required.

Corncob biochar supplementation improves nutrient digestibility, fattening performance and carcass characteristics of fattening sheep.

Corncob is a cheap source for biochar in developing countries. No studies reported on use of biochar as sheep fattening supplement. The goal of this study is to determine the effect of corncob biochar supplementation on growth performance and carcass characteristics of sheep. Twenty-four Horro yearling rams (18.6±0.938kg live weight) were randomly distributed to four groups, control (300g/day concentrate+local hay ad libitum), BC1.5 (control +1.5g/day biochar), BC3 (control +3g/day biochar) and BC4.5 (control +4.5/day biochar). The experimental concentrate consisted of 200g/day wheat bran and 100g/day Noug cake. The study consisted of a growth trial of 111 days followed by a digestibility trial of 10 days. Carcass characteristics for all rams were recorded at the end of the trial. Dry matter intake, crude protein intake, dry matter digestibility and acid detergent fibre digestibility of BC1.5 were significantly higher than the control. Corncob biochar supplementation significantly improved daily weight gain and feed conversion ratio of the rams. Supplementation sheep with corncob biochar improved significantly dressing percentage, hindquarters weight, forequarters weight, ribs weight, brisket weigh and rib eye muscle area. There was a significant effect of the dietary treatment on weight of internal organs; however, they were all within the normal range of sheep. Corncob biochar supplementation would be recommended at a level of 1.5g/day to improve growth performance and carcass characteristics of sheep.

Genomic evaluation of carcass traits of Korean beef cattle Hanwoo using a single-step marker effect model

Hanwoo beef cattle are well known for the flavor and tenderness of their meat. Genetic improvement programs have been extremely successful over the last 40 yr. Recently, genomic selection was initiated in Hanwoo to enhance genetic progress. Routine genomic evaluation based on the single-step breeding value model was implemented in 2020 for all economically important traits. In this study, we tested a single-step marker effect model for the genomic evaluation of four carcass traits, namely, carcass weight (CW), eye muscle area, backfat thickness, and marbling score. In total, 8,023,666 animals with carcass records were jointly evaluated, including 29,965 genotyped animals. To assess the prediction stability of the single-step model, carcass data from the last 4 yr were removed in a forward validation study. The estimated genomic breeding values (GEBV) of the validation animals and other animals were compared between the truncated and full evaluations. A parallel conventional best linear unbiased prediction (BLUP) evaluation with either the full or the truncated dataset was also conducted for comparison with the single-step model. The estimates of the marker effect from the truncated evaluation were highly correlated with those from the full evaluation, ranging from 0.88 to 0.92. The regression coefficients of the estimates of the marker effect for the full and truncated evaluations were close to their expected value of 1, indicating unbiased estimates for all carcass traits. Estimates of the marker effect revealed three chromosomal regions (chromosomes 4, 6, and 14) harboring the major genes for CW in Hanwoo. For validation of cows or steers, the single-step model had a much higher R2 value for the linear regression model than the conventional BLUP model. Based on the regression intercept and slope of the validation, the single-step evaluation was neither inflated nor deflated. For genotyped animals, the estimated GEBV from the full and truncated evaluations were more correlated than the estimated breeding values from the two conventional BLUP evaluations. The single-step model provided a more accurate and stable evaluation over time.