Effects of early high nutrition related to metabolic imprinting events on growth, carcass characteristics, and meat quality of grass-fed Wagyu (Japanese Black cattle)

Performance, nutrient digestibilities, and metabolic profiles of Holstein calves fed whole milk or milk replacer at 2 feeding levels

The macronutrient composition of common milk replacers (MR) largely differs from bovine whole milk (WM). These differences are more nutritionally relevant when calves receive higher milk allowances. Therefore, the present study compared fresh WM with a conventional MR fed at 2 level of feeding allowances evaluating growth performance, apparent total-tract nutrient digestibilities, N balance, and serum metabolite profiles in calves. Newborn male Holstein calves (n = 48; 1.96 ± 0.99 d of age; 45.0 ± 4.37 kg BW) were blocked by arrival date and age. Calves in each block were then randomly assigned to the 4 treatments (n = 12 per treatment): MR or WM at a high (9.0 L/d) or low feeding allowance (4.5 L/d) fed 3 times daily. Calves were weaned between wk 6 and 10 following the introduction of the starter feed in wk 6. The study ended 13 wk after the arrival at the facility. Blood and body weights were collected on arrival, and weekly thereafter. Total 24h-collection periods of feces and urine was performed at wk 2, 4, 5, 7, 9, 11, and 13. Remarkably, no interactions were observed between liquid feed and level of supply. Calves fed MR had higher ADG during the preweaning phase than to calves fed WM. However, calves fed WM had an increased growth rate postweaning, resulting in no difference in BW at the end of the study. Calves fed WM had a higher apparent crude fat digestibility during the weaning period. Metabolic N efficiency, expressed as N balance relative to digestible N supply, was higher during the preweaning phase, but tended to be lower during the postweaning phase for calves fed MR as compared with calves fed WM. In the preweaning period, serum glucose, BHB, nonesterified fatty acids (NEFA), total protein (TP), urea, albumin, globulin, triglyceride (TG), and cholesterol were influenced by liquid feed source. Carryover effects of milk source on TG and TP were observed during the postweaning period. As expected, calves fed a high milk allowance showed better ADG at preweaning and were consistently heavier throughout the study than calves fed a low milk allowance. Feeding a high milk allowance did not negatively affect nutrient digestibility during the postweaning phase. In the preweaning phase, milk allowance affected glucose and cholesterol metabolism, whereas TG, TP, albumin, and NEFA concentrations were affected during the postweaning period. From a single oral dose of indigestible markers (Cr-EDTA, lactulose, and d-mannitol), calves fed a high milk allowance showed greater urinary recovery of all markers after 6 h of collection, but not after 24 h. Calves fed a high milk allowance had a higher proportion of days with lower fecal scores during the preweaning phase. In conclusion, the serum metabolite profiles of calves throughout the study were highly influenced by milk source. Higher milk allowance increased growth performance and had no adverse effects on starter feed intake or nutrient digestibility in the postweaning phase. The multiple effects described for milk source and level of supply were overall independent, presenting no relevant interactions.

Effects of milk replacer composition on growth and development of beef × dairy crossbred calves

The production of crossbred beef × dairy (B × D) calves is increasing; however, evaluation of pre-weaning feeding strategies for B × D calves is limited. We hypothesized that both male and female B × D calves fed added fat and protein through milk replacer would have increased muscle growth, muscle fiber cross-sectional area, average daily gain, BW, and morphometric measurements. We also hypothesized that calves fed the additional fat and protein milk replacer would have upregulation of regulatory genes involved in muscle hypertrophy. SimAngus × Holstein calves (n = 42) were assigned to one of two milk replacers: 30.0% crude protein (CP), 32% crude fat (CF) milk replacer (HPHF, n = 11 males, 11 females), or 22% CP, 20% CF milk replacer (CON, n = 10 males, 10 females) from 0 to 8 wk of age. B × D calves were weighed at birth and weekly thereafter. At week 2 and 8, longissimus muscle biopsies were collected for muscle fiber cross-sectional area (CSA) or gene expression analysis. Ultrasounds were performed at 4 and 8 wk of age to quantify ribeye area (REA), and backfat and rump fat thickness. Morphometric measurements, BW, CSA, and ultrasound data were analyzed with PROC MIXED with animal as the subject and fixed effects of milk replacer, age, sex, and their interactions. Gene expression data were analyzed in R Studio. Calves that consumed the HPHF milk replacer were heavier than calves consuming the CON milk replacer (HPHF: 70.7 ± 0.39 kg; CON: 68.5 ± 0.41 kg; P < 0.01). At 8 wk of age, HPHF calves tended to have 14% larger muscle fiber CSA than CON calves (P = 0.06). No differences due to diet were observed for REA or fat thickness (P ≥ 0.38). Expression of MyoD tended to be 34% greater in CON females than HPHF females at 2 wk (P = 0.06), but at 8 wk, HPHF females tended to express 39% more MyoD than CON females (P = 0.09). Myogenin expression was 3% greater in CON calves than HPHF calves at 2 wk (P = 0.02), and CON females tended to express 52% more IGF-1 than HPHF females (P = 0.07). Feeding a milk replacer with a protein and fat content similar to beef cow milk improves B × D calf growth compared with a conventional milk replacer with less protein and fat. Improvements in early growth may improve B × D carcass quality and quantity, with the potential to increase return to the producer.

A review of emerging technologies, nutritional practices, and management strategies to improve intramuscular fat composition in beef cattle

The flavour, tenderness and juiciness of the beef are all impacted by the composition of the intramuscular fat (IMF), which is a key determinant of beef quality. Thus, enhancing the IMF composition of beef cattle has become a major area of research. Consequently, the aim of this paper was to provide insight and synthesis into the emerging technologies, nutritional practices and management strategies to improve IMF composition in beef cattle. This review paper examined the current knowledge of management techniques and nutritional approaches relevant to cattle farming in the beef industry. It includes a thorough investigation of animal handling, weaning age, castration, breed selection, sex determination, environmental factors, grazing methods, slaughter weight and age. Additionally, it rigorously explored dietary energy levels and optimization of fatty acid profiles, as well as the use of feed additives and hormone implant techniques with their associated regulations. The paper also delved into emerging technologies that are shaping future beef production, such as genomic selection methods, genome editing techniques, epigenomic analyses, microbiome manipulation strategies, transcriptomic profiling approaches and metabolomics analyses. In conclusion, a holistic approach combining genomic, nutritional and management strategies is imperative for achieving targeted IMF content and ensuring high-quality beef production.

Inbreeding depression and runs of homozygosity islands in Asturiana de los Valles cattle breed after 30 years of selection

Inbreeding depression results in a decrease in the average phenotypic values of affected traits. It has been traditionally estimated from pedigree-based inbreeding coefficients. However, with the development of single-nucleotide polymorphism arrays, novel methods were developed for calculating the inbreeding coefficient, and consequently, inbreeding depression. The aim of the study was to analyse inbreeding depression in 6 growth and 2 reproductive traits in the Asturiana de los Valles cattle breed using both genealogical and molecular information. The pedigree group comprised 225,848 records and an average equivalent number of complete generations of 2.3. The molecular data comprised genotypes of 2693 animals using the Affymetrix medium-density chip. Using the pedigree information, three different inbreeding coefficients were estimated for the genotyped animals: the full pedigree coefficient (FPED), and the recent and ancient inbreeding coefficients based on the information of the last three generations (FPED<3G) and until the last three generations (FPED>3G), respectively. Using the molecular data, seven inbreeding coefficients were calculated. Four of them were estimated based on runs of homozygosity (ROH), considering (1) the total length (FROH), (2) segments shorter than 4 megabases (FROH<4), (3) between 4 and 17 megabases (FROH4-17), and (4) longer than 17 Mb (FROH>17). Additionally, the three inbreeding coefficients implemented in the Plink software (FHAT1-3) were estimated. Inbreeding depression was estimated using linear mixed-effects model with inbreeding coefficients used as covariates. All analysed traits (birth weight, preweaning average daily gain, weaning weight adjusted at 180 days, carcass weight, calving ease, age at first calving, calving interval) showed a statistically significant non-zero effect of inbreeding depression estimated from the pedigree group, except for the Postweaning Average Daily Gain trait. When inbreeding coefficients were based on the genomic group, statistically significant inbreeding depression was observed for two traits, Preweaning Average Daily Gain and Weaning Weight based on FROH, FROH>17, and FHAT3 inbreeding coefficients. Nevertheless, similar to inbreeding depression estimated based on pedigree information, estimates of inbreeding depression based on genomic information had no relevant economic impact. Despite this, from a long-term perspective, genotyped data could be included to maximize genetic progress in genetic programs following an optimal genetic contribution strategy and to consider individual inbreeding load instead global inbreeding. ROH islands were identified on chromosomes 2, 3, 8, 10, and 16. Such regions contain several candidate genes for growth development, intramuscular fat, body weight and lipid metabolism that are related to production traits selected in Asturiana de los Valles breed.

Phenotypic relationships between meat quality parameters and residual feed intake in Japanese black Wagyu cattle

Japanese black Wagyu cattle are renowned for producing some of the world's most highly valued and recognized beef with exceptional marbling. Therefore, the primary focus of genetic selection for Wagyu cattle has historically been on meat quality, particularly achieving high marbling levels. However, even when the price of the final product is high, production costs also remain high, especially considering that most of the feed has to be imported. The objective of this study was to evaluate phenotypic relationships between feed efficiency, specifically residual feed intake (RFI), as the most utilized efficiency index in cattle, and various meat quality parameters in Japanese black cattle in order to determine if a common phenotypic selection for these parameters could be feasible. For this, a total of 39 Wagyu cattle were evaluated for feed efficiency over their entire fattening period (900 d), with a focus on RFI as a key indicator. Animals were fed high-starch diets with vitamin A deprivation to achieve the desired marbling. Results revealed positive correlations between feed efficiency and meat quality in Wagyu cattle. Specifically, animals with higher feed efficiency exhibited superior meat quality traits, including firmness, marbling, and overall meat rating. When comparing the 20 most extreme RFI individuals (10 most and 10 least efficient), we observed that efficient RFI animals showed increased marbling levels (+13.2%, P = 0.05) and ranking quality (+12%, P = 0.06) of the meat. In conclusion, this research contributes to understanding the interplay between feed efficiency and meat quality in Japanese black Wagyu cattle. Phenotypic correlations observed suggest the possibility of incorporating RFI criteria into genetic selection programs without compromising the prized meat quality traits of Wagyu beef.

Comparison of Pure and Crossbred Japanese Black Steers in Growth Performance and Metabolic Features from Birth to Slaughter at a Spanish Fattening Farm

Simple Summary

Cattle growth performance is a determinant of beef production. Nowadays, customers demand specialized, high-quality beef products produced according to stringent health and welfare standards. Intramuscular fat, or marbling, improves beef quality, and the Japanese Black (Wagyu) is the breed with the highest rates of marbling. Wagyu steers are reared under specific conditions in Japan, which may differ from the conditions in other countries, and these differences may affect animal well-being and, therefore, growth rates and beef quality. The current study shows that purebred Wagyu and crossbred Wagyu-by-Angus steers that were raised at a cow–calf operation and fattening system in Spain with no exercise restriction, high welfare, and a local diet high in olein content showed appropriate growth and fattening rates, health status, and metabolic development. Wagyu crossbred steers did not show substantially faster growth than purebred Wagyu animals, so they may not be as profitable as purebred Japanese Black in this type of production system.

Abstract

Japanese Black (Wagyu) cattle produce high-quality beef. However, whether Wagyu steers can be profitably raised under conditions different than the traditional Japanese ones remains unclear. From 2018 to 2020, we raised 262 Wagyu purebred steers, 103 Wagyu-by-Angus (Wangus) crossbred steers, and 43 Angus-by-European (ACL) crossbred steers on a Spanish farm with high welfare standards and a locally sourced, high-olein diet. Factors and factors’ interactions impacting steer growth were analyzed using generalized linear models. ACL steers grew faster than the other two groups, with Wangus showing intermediate fattening and muscle development. Average daily weight gains (kg/day) were 0.916 for Wagyu, 1.046 for Wangus, and 1.293 for ACL during the weaning to growing period, and 0.628 for Wagyu, 0.64 for Wangus, and 0.802 for ACL during the growing to fattening phase. ACL showed the lowest marbling rates. Wagyu and Wangus usually showed higher cholesterol, triglycerides, and high-density lipoprotein than ACL. ACL calves may experience greater stress at weaning, as suggested by higher glucose, lactate, and β-hydroxybutyrate than the other groups. The results suggest that Wagyu and Wangus steers showed adequate growth, health, and metabolic development in this type of production system, with Wagyu purebreds probably being more profitable than Wangus crossbreeds.

Main regulatory factors of marbling level in beef cattle

The content of intramuscular fat (IMF), that determines marbling levels is considered as one of the vital factors influencing beef sensory quality including tenderness, juiciness, flavour and colour. The IMF formation in cattle commences around six months after conception, and continuously grows throughout the life of the animal. The accumulation of marbling is remarkably affected by genetic, sexual, nutritional and management factors. In this review, the adipogenesis and lipogenesis process regulated by various factors and genes during fetal and growing stages is briefly presented. We also discuss the findings of recent studies on the effects of breed, gene, heritability and gender on the marbling accumulation. Various research reported that feeding during pregnancy, concentrate to roughage ratios and the supplementation or restriction of vitamin A, C, and D are crucial nutritional factors affecting the formation and development of IMF. Castration and early weaning combined with high energy feeding are effective management strategies for improving the accumulation of IMF. Furthermore, age and weight at slaughter are also reviewed because they have significant effects on marbling levels. The combination of several factors could positively affect the improvement of the IMF deposition. Therefore, advanced strategies that simultaneously apply genetic, sexual, nutritional and management factors to achieve desired IMF content without detrimental impacts on feed efficiency in high-marbling beef production are essential.