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Simple Summary: This paper summarizes the results of a study on the age at first calving (AFC) in Angus cows bred in Hungary. This trait is critical for economic and sustainability reasons due to its relationship with effectiveness and profitability. The results show significant effects of the birth season, herd, and the sire on this trait. No phenotypic or genetic changes were found during the 23-year study period. However, higher heritability estimates than previously reported suggest the possibility of the selection of the AFC in the Angus population. This study aimed to examine the age at first calving (AFC) in Hungarian Angus herds. This study was conducted on the basis of data from 2955 registered cows, classified into five groups (based on different Angus types), and 200 breeding bulls, which were the sires of the cows. The data were made available by the Hungarian Hereford, Angus, and Galloway Breeders' Association. The variance and covariance components, heritability, breeding value (BV), and genetic trends of AFC between 1998 and 2021 were evaluated. A general linear model (univariate analysis of variance) was used to examine the various effects, while best linear unbiased prediction was used to estimate the population genetic parameters and BV, and linear regression analysis was used for the trend analysis. The average AFC obtained was 28.1 ± 0.1 months (SD = 5.3 months), showing a relatively large variance (CV = 18.9%). The environmental factors that influenced the development of the phenotype were the cow's birth season (28.99%, p < 0.01), cow's birth year (28.7%, p < 0.01), the cow's sire (18.32%, p < 0.01), and the herd (11.77, p < 0.05). The cow's color variant (8.10%, p > 0.05) was not significant and did not influence the AFC in this study. The direct heritability of AFC (h2 = 0.51 ± 0.06) was higher than data in the literature (0.38 ± 0.05); however, the maternal heritability was low (h2m = 0.00 ± 0.03). The correlation between direct and maternal genetic effects was zero (rdm = −0.97 ± 1.00). The phenotypic trend of AFC increased by +0.03 months per year, which was not statistically significant. The genetic trend calculation showed no significant changes. Based on the h2 and BV results, it seems that selecting a suitable sire can effectively reduce the AFC of daughters. Since AFC is also an important trait in economic terms, it would be appropriate to include AFC BV in the bull catalog. [ABSTRACT FROM AUTHOR]

Simple Summary: Beef cattle production has improved to achieve consumers' preferences, including meat quality and human-health-related indexes. Wagyu (WY) breed is Japanese cattle with high intramuscular fat infiltration and rich in unsaturated fatty acids. Most Wagyu beef cattle are raised in Japan. Our objective was to describe Wagyu, Wagyu-by-Angus (Wangus, WN), and Angus-by-Charolaise-Limousine (ACL) beef produced in a Spanish fattening system with high-olein diets, regarding the fat profile, health-related indexes and the metabolic biomarkers prior to slaughtering. Blood lipid-related metabolites, except for non-esterified fatty acids (NEFA) and low-density level cholesterol (LDL), were higher in WY and WN than in ACL, while glucose was lower in WY and WN. Leptin was higher in WN than in ACL. Nutritional analyses showed higher fat infiltration in WY and WN steers than ACL animals for both meat cuts (sirloin and entrecote), including three-fold higher content. Wagyu beef had the highest intramuscular fat in sirloin (51.5% vs. 21.9%) and entrecote (59.6% vs. 27.6%) vs. ACL animals. Wagyu entrecote contained more unsaturated fatty acids (55.8% vs. 53.0%) and more oleic acids (47.5% vs. 43.3%) than ACL' beef. Wagyu and WN entrecote showed better atherogenic (0.6 and 0.55 vs. 0.69), thrombogenicity (0.82 and 0.92 vs. 1.1), and hypocholesterolemic/hypercholesterolemic index (1.9 and 2.1 vs. 1.7; all p < 0.001) than ACL's beef. In brief, the fat profile and nutritional characteristics of beef depend on the fattening period, breed/crossbred, and cut of meat, with Wagyu and Wangus beef showing a healthier fat profile than ACL animals. A high intramuscular fat content characterizes Wagyu (WY) cattle breed. Our objective was to compare beef from WY, WY-by-Angus, or Wangus (WN) steers with European, Angus-by-Charolais-Limousine crossbred steers (ACL), considering metabolic biomarkers pre-slaughtering and nutritional characteristics, including health-related indexes of the lipid fraction. The fattening system with olein-rich diets and no exercise restriction included 82 steers, 24 WY, 29 WN, and 29 ACL. The slaughter ages and weights were (median and interquartile range) 38.4 mo.-old (34.9–40.3 mo.) and 840 kg (785–895 kg) for WY; for WN, 30.6 mo. (26.9–36.5 mo.) and 832 kg (802–875 kg), and for ACL steers, 20.3 mo.-old (19.0–22.7 mo.) and 780 kg (715–852 kg). Blood lipid-related metabolites, except for non-esterified fatty acids (NEFA) and low-density level cholesterol (LDL), were higher in WY and WN than in ACL, while glucose was lower in WY and WN. Leptin was higher in WN than in ACL. Pre-slaughtering values of plasma HDL underscored as a possible metabolic biomarker directly related to beef quality. The amino-acid content in beef did not differ among experimental groups, except for more crude protein in ACL. Compared to ACL, WY steers showed higher intramuscular fat in sirloin (51.5 vs. 21.9%) and entrecote (59.6 vs. 27.6%), more unsaturated fatty acids in entrecote (55.8 vs. 53.0%), and more oleic acid in sirloin (46 vs. 41.3%) and entrecote (47.5 vs. 43.3%). Compared to ACL entrecote, WY and WN showed better atherogenic (0.6 and 0.55 vs. 0.69), thrombogenicity (0.82 and 0.92 vs. 1.1), and hypocholesterolemic/hypercholesterolemic index (1.9 and 2.1 vs. 1.7). Therefore, beef's nutritional characteristics depend on breed/crossbred, slaughtering age and cut, with WY and WN entrecote samples showing a healthier lipid fraction. [ABSTRACT FROM AUTHOR]

Simple Summary: Microorganisms inhabiting the gut influence the health and productivity of livestock. Studies in ruminants including beef cattle show that ruminal microorganisms can help convert poor-quality or indigestible feed into nutrients, thereby influencing economically important traits like feed conversion efficiency and meat quality (e.g., marbling), and also interact with receptors on intestinal epithelial cells to regulate a variety of physiological processes including immune responses. Studies have also shown that the proportions of different groups of microorganisms in the gut are influenced by exposure to stress. In beef cattle, given that most cattle are finished on feedlots, induction into feedlots can expose cattle to stress due to transportation, change in diet and change in the handling and management of animals. Therefore, the primary objective of this study was to characterise how gut microorganisms change over time when cattle are inducted into feedlots. The results indicate that there are significant changes in the profiles of gut microorganisms in cattle that are visible soon after feedlot placement. These changes primarily include a reduced diversity of microorganisms within the gut of individual cattle and increased differences in the types of microorganisms that inhabit the gut of different cattle. The microbial communities that inhabit the intestinal tract play an important role in modulating health and productivity. Environmental stressors can impact microbial communities, which can significantly influence host physiology. Cattle are subjected to several environmental stressors when placed on feedlots, such as transportation stress, exposure to feedlot environments and change in diet and management. Exposure to these stressors could influence host gut microbiota, which in turn, could potentially influence host health and performance. The aim of the current study was to characterise the temporal changes that occur in intestinal microbiota as a consequence of feedlot placement by profiling 16s rRNA sequences in rectal faecal samples. When faecal microbiome profiles were compared in terms of relative abundances and alpha diversity metrics, the results showed significant, observable changes in profiles 2 days post-feedlot induction. Furthermore, beta-diversity analysis indicated that the phylogenetic similarity between samples significantly decreased on day 2 (PERMANOVA, p < 0.001). These trends were suggestive of a short-term reduction in microbial diversity coupled with decreased similarity between animals. These changes warrant further investigation and could provide opportunities for improved performance, health and even welfare of feedlot cattle in future. [ABSTRACT FROM AUTHOR]

Dairy heifers in New Zealand are typically naturally mated by Jersey bulls to produce low-value non-replacement offspring sold for slaughter a few days after birth. Producing a beef-sired calf from a dairy heifer will increase the value of these calves for beef production but may compromise the subsequent career of the animals, in terms of milk production, rebreeding success, health, or survival of the heifer. This study aimed to determine the impact of low birthweight Angus and Hereford bulls versus breed-average Jersey bulls on the reproduction and production traits of first-calving dairy heifers. The experiment included 304 heifer-calf pairs over 2 years. Calves sired by Angus and Hereford bulls were 3.5–4.4 kg and 3.7–6.8 kg heavier than Jersey-sired calves and had a 4.2% and 9.3% incidence of assistance at birth for normally presented calves over the 2 years, respectively. No normally presented Jersey-sired calves were assisted. There was no difference in body condition score, pre-calving live weight, milk production, pregnancy rate, inter-calving interval, re-calving day, and 21-day re-calving rate of heifers mated to the different breeds of bulls. The results indicate that the Angus and Hereford bulls with low birthweight and high direct calving ease estimated breeding values (EBV) can be used to produce calves of greater value than Jersey-sired calves without impacting dairy heifer production. However, a small increase in assistance at calving could be expected. [ABSTRACT FROM AUTHOR]

Dystocia and perinatal mortality are major animal health, welfare and economic issues in beef suckler cow production. The objective of this study was to identify risk factors for dystocia and perinatal mortality and to analyze the relationships of both traits to external pelvic parameters in extensively kept beef suckler cows. Calving ease and calf survival were recorded for 785 births on five Angus cattle farms in Germany. The prevalence of dystocia and perinatal mortality was 3.4% and 4.3%, respectively. A hierarchical model was used to predict dystocia and perinatal mortality. First-parity dams had a higher probability of dystocia (p < 0.0001) than later-parity ones. Increasing birth weight was associated with an increasing risk for dystocia (p < 0.05). The probability of perinatal mortality (p < 0.0001) was higher in assisted births than in unassisted births. Calves from first-parity dams had a higher risk (p < 0.01) of being stillborn than calves from dams in later parities. An increase in the length of the pelvis was associated with an increase in odds for perinatal mortality (p < 0.001). In conclusion, the study indicates that dystocia and perinatal mortality are mainly problems in first-parity suckler cows. Concerning the predictive value of external pelvic parameters, further research is necessary. [ABSTRACT FROM AUTHOR]