Tenderness profiles of ten muscles from F1 Bos indicus x Bos taurus and Bos taurus cattle cooked as steaks and roasts

Distribution of ivermectin residues in different Zebu cattle tissues and its stability in thermally processed canned meat

Ivermectin (IVM) is one of the most widely used antiparasitic drugs worldwide and has become the drug of choice for anthelmintic and tick treatment in beef cattle production. Drugs used in production animals requires a withdrawal period after treatment to avoid residual concentrations above the defined maximun residue level (MRL). The aims of this study were to quantify the residue level of IVM in different muscles of cattle at several different time periods following 1% or 3.15% IVM administration and also determined whether the residue concentration was affected by industrial thermal processing. Distinct pattern of IVM residue distribution was observed in each tissue evaluated. After completed the IVM withdrawal periods, nearly all tissues presented IVM residues concentration below the established Codex Alimentarius MRLs, except for the injection site, which means that the calculation to determine the withdrawal period for the injection site should not be the same as that used for standard edible tissues. Also, the thermal processing to which canned products are exposed causes changes in the levels of quantified residues in comparison to raw products, which must be taken into consideration in surveillance program assessments and generates concerns regarding the possibility of residue limit violation in importing markets.

Graphical abstract

Muscle-Specific Effects of Genotype, Animal Age, and Wet Aging Duration on Beef Color, Tenderness, and Sensory Characteristics

This study investigated the effects of genotype, animal age, muscle type, and aging duration on meat quality characteristics of Psoas major (PM), Longissimus thoracis (LT), Longissimus lumborum (LL), and Gluteus Medius (GM) muscles. The PM, LT, LL, and GM muscles were sourced from a total of 32 bulls, consisting of 16 humped (Bos indicus) and 16 humpless (Bos indicus × Bos taurus) bulls aged 21 ± 2 and 30 ± 3 months. The muscles underwent aging durations of 0, 7, and 14 days. Meat pH, color, drip loss, cooking loss, instrumental shear force, lipid oxidation (thiobarbituric acid reactive substances/TBARS), and sensory analysis were performed. Our results indicated that humped bulls had superior color, while humpless bulls exhibited better sensory characteristics. The 30 ± 3 months of age bulls showed improved color and sensory characteristics with higher TBARs values than the 21 ± 2 months of age bulls. The color, tenderness, and sensory characteristics improved in PM and LT at 7 days, whereas in LL and GM they improved at 14 days. PM showed better tenderness and overall acceptability among different muscles, while LL showed better color and oxidative stability. This study suggested the necessity of muscle-specific aging strategies to enhance the meat quality characteristics of humped and humpless bulls. Further research could explore additional aging durations and other muscle types to better understand their impact on meat quality characteristics.

Contribution of intramuscular connective tissue and its structural components on meat tenderness-revisited: a review

The tenderness of meat influences consumers' perceptions of its quality. Meat tenderness is a key quality characteristic that influences consumer satisfaction, repeat purchases, and willingness to pay higher prices for meat. Muscle fibers, connective tissues, and adipocytes are the main structural components of meat that contribute to its tenderness and texture. In the present review, we have focused on the role of connective tissue and its components in meat tenderness, specifically perimysial intramuscular connective tissue (IMCT) and its concept as an immutable "background toughness." The collagen contribution to cooked meat toughness can be altered by animal diet, compensatory growth, slaughter age, aging, and cooking. As well, progressive thickening of the perimysium leads to a progressive increase in shear force values in beef, pork, chicken, and this may occur prior to adipocyte formation as cattle finish in feedlots. Conversely, adipocyte accumulation in the perimysium can decrease cooked meat shear force, suggesting that the contribution of IMCT to meat toughness is complex and driven by both collagen structure and content. This review provides a theoretical foundation of information to modify IMCT components to improve meat tenderness.

Genome-Wide DNA Methylation Differences between Bos indicus and Bos taurus

Disease risk is a persistent problem in domestic cattle farming, while economic traits are the main concern. This study aimed to reveal the epigenetic basis for differences between zebu (Bos indicus) and taurine cattle (Bos taurus) in disease, disease resistance, and economic traits, and provide a theoretical basis for the genetic improvement of domestic cattle. In this study, whole genome bisulfite sequencing (WGBS) was used to analyze the whole-genome methylation of spleen and liver samples from Yunnan zebu and Holstein cattle. In the genome-wide methylation pattern analysis, it was found that the methylation pattern of all samples was dominated by the CG type, which accounted for >94.9%. The DNA methylation levels of different functional regions and transcriptional elements in the CG background varied widely. However, the methylation levels of different samples in the same functional regions or transcriptional elements did not differ significantly. In addition, we identified a large number of differentially methylation region (DMR) in both the spleen and liver groups, of which 4713 and 4663 were annotated to functional elements, and most of them were annotated to the intronic and exonic regions of genes. GO and KEGG functional analysis of the same differentially methylation region (DMG) in the spleen and liver groups revealed that significantly enriched pathways were involved in neurological, disease, and growth functions. As a result of the results of DMR localization, we screened six genes (DNM3, INPP4B, PLD, PCYT1B, KCNN2, and SLIT3) that were tissue-specific candidates for economic traits, disease, and disease resistance in Yunnan zebu. In this study, DNA methylation was used to construct links between genotypes and phenotypes in domestic cattle, providing useful information for further screening of epigenetic molecular markers in zebu and taurine cattle.

Genome-Wide Selection Signatures and Human-Mediated Introgression Events in Bos taurus indicus-influenced Composite Beef Cattle

Genetic introgression from interbreeding hybridization of European Bos taurus taurus (EBT) and Indian Bos taurus indicus (IBI) cattle breeds have been widely used to combine the climatic resilience of the IBI cattle and the higher productivity of EBT when forming new composite beef cattle (CB) populations. The subsequent breeding strategies have shifted their initial genomic compositions. To uncover population structure, signatures of selection, and potential introgression events in CB populations, high-density genotypes [containing 492,954 single nucleotide polymorphisms (SNPs) after the quality control] of 486 individuals from 15 cattle breeds, including EBT, IBI, and CB populations, along with two Bos grunniens genotypes as outgroup were used in this study. Then, in-depth population genetics analyses were performed for three CB breeds of Beefmaster, Brangus, and Santa Gertrudis. Neighbor-joining, principal components, and admixture analyses confirmed the historical introgression of EBT and IBI haplotypes into CB breeds. The f_dM statistics revealed that only 12.9% of CB populations' genetic components are of IBI origin. The results of signatures of selection analysis indicated different patterns of selection signals in the three CB breeds with primary pressure on pathways involved in protein processing and stress response in Beefmaster, cell proliferation regulation and immune response in Brangus, and amino acids and glucose metabolisms in Santa Gertrudis. An average of >90% of genomic regions underlying selection signatures were of EBT origin in the studied CB populations. Investigating the CB breeds' genome allows the estimation of EBT and IBI ancestral proportions and the locations within the genome where either taurine or indicine origin alleles are under selective pressure. Such findings highlight various opportunities to control the selection process more efficiently and explore complementarity at the genomic level in CB populations.

The effect of complete feed to carcass characteristics and meat quality of male Bali cattle fattened in West Timor, Indonesia

Aim:

This research aimed to know the effect of the use of complete feed on Bali cattle fattening performance seen from the carcass characteristics.

Materials and Methods:

The cattle employed in this research were 12 male Bali cattle aged between 2 and 2.5 years old based on the teeth estimation. The average initial body weight of the cattle during the research was 181.50±16.51 kg. The complete feed contained Gliricidia sepium, natural grass, ground corn, bran pollard, and rice bran which have been compiled into three types of ration of T1, T2, and T3. The T₁ ration contained standard crude protein (CP) and high energy (11% CP; 72% total digestible nutrient [TDN]), and T₂ contained medium protein and high energy (13% CP; 72% TDN), while T₃ ration contained high protein and high energy (%15 CP; 72% TDN).

Results:

The meat percentage of T2 and T3 was relatively the same, but higher than T1 (p<0.05). The bone percentage and meat: A bone ratio of T2 was higher than T1; in contrast, and T3 was relatively the same with T2 and T1 (p<0.05). The weight of slaughter, carcass percentage, and weight of meat, bone, and fat were relatively the same among the treatments.

Conclusion:

The application of complete feed with protein source from G. sepium with CP and TDN of 13 and 72%, respectively, can improve carcass percentage and meat: A bone ratio of male Bali cattle fattening. The treatments have not had a positive effect on slaughter weight (kg), hot and cool carcass weight (kg), meat and fat weight (kg), fat percentage, and non-carcass (kg).

Alternative cutting methods and dry aging reduce the shear force of hot boned beef striploin in Bos indicus cattle

Hot boning (HB) is an economical processing technique often resulting in poorer meat quality and tenderness. This study tested a method of partial HB, where the short loin section was removed from the hot carcass and chilled, with the striploin remained in the skeletal system. Thirty six yearling Bos indicus steers carcasses were subjected to either low, high or no electrical stimulation and each side allocated to a cutting treatment of HB, partial HB and conventional (Achillies hung). Striploins were divided into 3 and aged for 5, 14 and 28 days. Warner Bratzler Shear force (WBSF) and sarcomere length were tested. Partial HB resulted in greater tenderization without aging compared to HB. However, optimized electrical stimulation was a requirement. Treatment did not influence sarcomere length. The study also tested the impact of Dry aging of HB striploins, which resulted in further increases in tenderness at 28 days of aging compared to wet aged product, reducing WBSF by 9 N.

Application of proteomic to investigate the post-mortem tenderization rate of different horse muscles

The aim of this study was to evaluate the effect of post-mortem aging on tenderness development and proteolysis of myofibrillar proteins in 3 different horse muscles. Warner-Bratzler shear force decreased during aging in all muscles, showing the lowest values in longissimus lumborum (LL) in all sampling points. Myofibril fragmentation index significantly increased in LL and semimembranosus (SM) muscles throughout aging time whereas in semitendinosus (ST) it increased after 14 days of aging. Proteomics analysis revealed the major content of intact myofibrillar proteins with high molecular weight in ST muscle in the first phase of aging, while, after 14 days a higher accumulation of TnT-derived polypeptides and spots isoforms ascribed to MLC2 and MLC1 proteins were found. Data highlight that aging affects the meat tenderness and proteolysis with different intensities in each muscle and suggest that a more extensive post-mortem proteolysis occurred in ST muscle.

Honduran and U.S. Consumer Assessment of Beef from Various Production Systems with or Without Marinating

Our objective was to evaluate the effects of different Honduran cattle production systems, enhancement, and country of origin on palatability of the longissimus muscle aged 21 d postmortem as determined by U.S. and Honduran consumers (n = 240/country). U.S.-sourced strip loins (n = 10/treatment) were selected: USDA Select (SE) and Top (upper 2/3) Choice (TC). Honduran-sourced strip loins (n = 10/treatment) included: 1) dual-purpose bulls, raised on native pasture (HDP), 2) F1 crossbred Brahman bulls finished on a corn-based grain diet for 180 d (HCF), and 3) purebred Brahman bulls finished on a sugarcane-based diet for 180 d (HSC). Ten additional strip loins from each Honduran treatment were selected and enhanced (E; 112% ± 3.5%) with water, salt, and tripolyphosphate, resulting in EHDP, EHCF, and EHSC. Steaks were cooked to 77°C prior to consumer evaluation of tenderness, juiciness, and flavor and overall liking, with classification of each trait as acceptable or unacceptable. Consumers indicated if they were willing to pay 0, 3, 6, or 10 USD/0.45 kg. Consumer data were analyzed using the GLIMMIX procedure of SAS as a split plot design, with treatment as the whole plot factor and country and the country × treatment interaction as the subplot factors, including panel as a random effect. The EHCF had greater (P &lt; 0.05) scores for tenderness, juiciness, flavor and overall liking. No differences (P &gt; 0.05) were found between TC and SE when scoring palatability traits, but more (P &lt; 0.05) consumers found TC acceptable for juiciness compared to SE. Honduran consumers ranked all palatability traits greater than U.S consumers and found a greater percentage of samples acceptable for tenderness (P &lt; 0.05). Enhancement of Honduran treatments had a positive effect on palatability traits, as well as the acceptability of those traits. Regardless of the differences in breeds, using high-energy diets and enhancement resulted in greater palatability scores.

Bos indicus cattle possess greater basal concentrations of HSP27, alpha B-crystallin, and HSP70 in skeletal muscle in vivo compared with cattle

The objectives of the present study were to evaluate the basal concentrations of heat shock proteins (HSP) between and cattle and to determine if HSP basal concentrations change as an animal matures. A total of 40 cattle were used in a 2 × 2 factorial design to evaluate the effects of genotype and age (heifers and mature cows) on basal concentrations of heat shock protein 27 (HSP27), α B-crystallin (Cryab), and heat shock protein 70 (HSP70). Each experimental group of 10 animals was sampled on a separate day over a period of 4 wk during July 2014. A muscle sample was collected from the longissimus thoracis (LT) and concentrations of HSP were quantified using ELISA. There were no significant differences in HSP concentration for the interaction between age and genotype or for age alone. cattle had greater ( < 0.05) basal concentrations of HSP27, Cryab, and HSP70 in the LT than cattle. The results of this study show that basal in vivo HSP concentrations differ between and cattle. However, further studies are needed to investigate the relationship between HSP concentrations and meat tenderness with respect to genotypes to see if HSP concentrations account for at least some variability in tenderness differences.

Zilpaterol hydrochloride improves feed efficiency and changes body composition in nonimplanted Nellore heifers

This research aimed to evaluate the effects of zilpaterol hydrochloride (ZH; MSD Animal Health, São Paulo, SP, Brazil) on the performance, carcass traits, serum metabolites, body composition, and gain composition of nonimplanted Nellore heifers. Nellore heifers ( = 72; average BW = 267 ± 16 kg; average 18 mo of age) were maintained in a feedlot system for 118 d. Heifers were separated into 2 groups: Control and ZH. The ZH group received ZH (8.3 mg/kg diet DM) for 30 d with 3 d of withdrawal before slaughter. Heifers were allotted to 18 pens, 9 pens per treatment, and assigned to a randomized block design. The animals were weighed, blood samples were collected, and subgroups of heifers were slaughtered at the beginning of supplementation and after 20 and 33 d to evaluate performance, blood metabolites, empty BW (EBW), and EBW composition. Hot carcass and kidney-pelvic fat weights were recorded at slaughter. At 24 h postmortem, carcasses were fabricated and the 9-10-11th rib (HH) section was removed from the primal rib to analyze moisture, protein, ash, and ether extract (EE) content in empty body (EB) and gain composition. Heifers fed ZH had gains in HCW that were 19.7 kg greater than controls, reflecting the 30% increase ( < 0.01) in ADG. There was no change in DMI, resulting in a 20% greater G:F ratio ( < 0.01) for heifers fed ZH. Heifers supplemented with ZH had carcass dressing percentages that were 3% greater than controls ( < 0.01), and there was also a 19% reduction in kidney-pelvic fat ( = 0.05) in ZH-treated heifers. Zilpaterol increased serum creatinine ( < 0.01), tended to increase ( = 0.06) serum triacylglycerol, decreased serum NEFA ( = 0.04), and tended to decrease ( = 0.06) serum glucose. The EBW composition was changed after 20 d of ZH supplementation ( = 0.02), with ZH increasing the moisture, ash, and protein contents, whereas carcass fat was decreased by ZH by 14%. Consequently, the carcass CP:EE ratio after 20 d was increased ( = 0.03) by 24% with ZH supplementation. There was no change on EBW composition after 30 d of ZH supplementation ( = 0.17). Regarding carcass gain composition, ZH increased EBW gain ( = 0.02) by 842 g/d from d 0 to d 30, EB protein gain by 221 g/d ( = 0.05) from d 0 to d 20, and by 180 g/d ( = 0.01) from d 0 to d 33. In conclusion, ZH supplementation in nonimplanted Nellore heifers altered the composition of body weight gain, promoting greater lean tissue deposition and improving feed efficiency.

The influence of diet on collagen content and quality attributes of infraspinatus muscle from Holstein-Friesian young bulls

The aim of the study was to determine effects of feeding intensity on collagen content and eating quality of infraspinatus (INF) muscle. Twenty Polish Holstein-Friesian bulls (11-month-old) were fed either intensively (I, n=10, with triticale meal addition to total mixed ration) or semi-intensively (SI, n=10, without triticale meal) before slaughter at 19months. The animals from I group showed higher body weight at the end of fattening, average daily gain and dressing percentage than SI group. The INF muscle from I treatment had higher fat content and the proportion of water-soluble collagen, whereas lower insoluble collagen content compared with SI treatment. There were no differences in shear force values, cooking loss and eating quality between the treatments. In conclusion, feeding Holstein-Friesian bulls with increased energy value fodder beneficially affected its slaughter value and collagen profile in infraspinatus muscle.

Immunocastration improves carcass traits and beef color attributes in Nellore and Nellore×Aberdeen Angus crossbred animals finished in feedlot

The objective was to examine the effects of immunocastration on carcass traits and meat quality of Nellore and Nellore×Aberdeen Angus male animals finished in feedlot. Surgically castrated, immunocastrated, and intact animals were finished in feedlot for 90 days. The animals were harvested, and carcass traits were evaluated. Carcasses were chilled, and one 2.5-cm steak was fabricated from Longissimus thoracis muscle. The steaks were individually vacuum packaged and frozen at -18 °C. Frozen steaks were thawed, and pH, instrumental color, cooking loss, and shear force were determined. Immunocastrated animals demonstrated greater (P<0.05) hot dressing percentage and cold dressing percentage than their surgically castrated counterparts. Furthermore, steaks from immunocastrated and surgically castrated animals exhibited greater redness (P<0.05) and lower darkness (P<0.05) than steaks from intact animals, indicating possible advantage in retailing. The results suggested that immunocastration may be utilized to improve carcass traits and beef color in feedlot-finished Nellore and Nellore×Aberdeen Angus males.

Genome-wide association study for backfat thickness in Canchim beef cattle using Random Forest approach

Background

Meat quality involves many traits, such as marbling, tenderness, juiciness, and backfat thickness, all of which require attention from livestock producers. Backfat thickness improvement by means of traditional selection techniques in Canchim beef cattle has been challenging due to its low heritability, and it is measured late in an animal’s life. Therefore, the implementation of new methodologies for identification of single nucleotide polymorphisms (SNPs) linked to backfat thickness are an important strategy for genetic improvement of carcass and meat quality.

Results

The set of SNPs identified by the random forest approach explained as much as 50% of the deregressed estimated breeding value (dEBV) variance associated with backfat thickness, and a small set of 5 SNPs were able to explain 34% of the dEBV for backfat thickness. Several quantitative trait loci (QTL) for fat-related traits were found in the surrounding areas of the SNPs, as well as many genes with roles in lipid metabolism.

Conclusions

These results provided a better understanding of the backfat deposition and regulation pathways, and can be considered a starting point for future implementation of a genomic selection program for backfat thickness in Canchim beef cattle.