Pregnant beef cow's nutrition and its effects on postnatal weight and carcass quality of their progeny

Fetal Programming and Its Effects on Meat Quality of Nellore Bulls

This work aimed to evaluate the effects of prenatal nutritional stimulation at different pregnancy stages on carcass traits and meat quality in bovine progeny. For this purpose, 63 Nellore bulls, born from cows submitted to three nutritional plans, were used: not programmed (NP), which did not receive protein supplementation; partially programmed (PP), which had protein-energy supplementation (0.3% of mean body weight of each batch) only in the final third of pregnancy; and full programming (FP), which received supplementation (0.3% of mean body weight of each batch) throughout pregnancy. The averages of parameters were submitted to the ANOVA, and the supplementation periods, which were different when p value < 0.05, were compared. Carcass weights and rib eye area (REA) did not differ between treatments (p > 0.05), but subcutaneous fat thickness (SFT) showed a tendency (p = 0.08) between groups. For lipids and marbling, no differences were found (p > 0.05). In the analyses of maturation time and shelf life, no difference was observed between treatments. However, there was a tendency between treatments at 14 days of maturation time for cooking loss (CL) (p = 0.08). Treatments did not affect shear force in the progenies (p > 0.05). Fetal programming had no effect on the meat quality of Nellore bulls.

Maternal Nutrition Affects Nitrogen Isotopic Signature in Blood Plasma of Beef Cattle Dams and Their Offspring

This study evaluated the effects of gestational supplementation strategy on nitrogen isotopic signature in blood plasma of beef cows and their progeny. The study comprised 15 pregnant Nellore cows divided into three different supplementation protocols: NP) non-programmed group; PP) cows receiving protein−energy supplement in the last third of pregnancy; and FP) cows receiving protein−energy supplement throughout the gestational period. Blood plasma from cows was sampled at the beginning of gestation, in the prepartum, and postpartum periods as well as from their calves at 30 and 180 days of age, for the analysis of stable isotope ratios 15 N/14 N. At pre- and postpartum periods, cows fed PP and FP presented greater abundance of δ15 N compared to NP (p < 0.05) at pre- and postpartum. All three groups showed significant differences (p < 0.05) in the postpartum period. The δ15 N values of calves at 30 days of age differed between the NP group and PP and FP groups (p < 0.05), with no difference (p > 0.05) at 180 days of age. The different gestational supplementation strategies influenced isotopic fractionation of nutrients of cows and their calves after birth, indicating effects on nutritional metabolism and cumulative behavior on isotope abundance related to consumption during gestation.

The Effects of Prenatal Diet on Calf Performance and Perspectives for Fetal Programming Studies: A Meta-Analytical Investigation

Simple Summary

Prenatal nutrition can reshape an animal’s developmental trajectory, with persistent long-term consequences for the progeny. In prenatal life, the effects induced by the intrauterine conditions can be expressed as changes in offspring growth and meat quality. Thus, there are diverse sources of variations that contribute to the variations reported for fetal-programming responses in beef cattle, making it difficult to interpret and apply the results. In this sense, finding a common factor among the studies with which to group them may offer an opportunity to quantify the fetal-programming effects holistically and to obtain more applicable responses. With the increasing number of publications, it is important to summarize the quantitative measurements available in the scientific literature. In the present study, data from 35 publications were used. We verified that there is a gap related to the effects of maternal nutrition to females, at the beginning of gestation, and in zebu and crossbred animals, indicating new perspectives for future fetal-programming studies. In summary, our findings highlight an association between prenatal energy and protein supply and its effects on the offspring birth weight, weaning weight, and the daily weight gain of pregnant beef cows during pregnancy.

Abstract

This meta-analysis aimed to identify knowledge gaps in the scientific literature on future fetal-programming studies and to investigate the factors that determine the performance of beef cows and their offspring. A dataset composed of 35 publications was used. The prenatal diet, body weight (BW), average daily gain (ADG) during pregnancy, and calf sex were elicited as possible modulators of the beef cows and their offspring performance. Then, the correlations between these variables and the outcomes of interest were investigated. A mixed multiple linear regression procedure was used to evaluate the relationships between the responses and all the possible explanatory variables. A knowledge gap was observed in studies focused on zebu animals, with respect to the offspring sex and the consequences of prenatal nutrition in early pregnancy. The absence of studies considering the possible effects promoted by the interactions between the different stressors’ sources during pregnancy was also detected. A regression analysis showed that prenatal diets with higher levels of protein improved the ADG of pregnant beef cows and that heavier cows give birth to heavier calves. Variations in the BW at weaning were related to the BW at birth and calf sex. Therefore, this research reinforces the importance of monitoring the prenatal nutrition of beef cows.

Long-term effects of early maternal undernutrition on the growth, physiological profiles, carcass and meat quality of male beef offspring

The effects of maternal undernutrition in early gestation on growth, metabolic and endocrine profiles, carcass and meat quality of male offspring in cattle were assessed. Twenty-one Parda de Montaña and 14 Pirenaica cows received a CONTROL (100% nutrition requirements) or a SUBNUT (65%) diet from day 0 to 82 of gestation and thereafter were fed to requirements until calf weaning at 4 months of age. The performance and physiological profiles of male offspring during an 8-month fattening period were analyzed. Bulls were slaughtered at 12 months of age, and their carcasses and meat color, tenderness and intramuscular fatty acid profile were evaluated. Maternal undernutrition increased plasma NEFAs and impaired the growth of Pirenaica bulls, resulting in lower weights at slaughter and fatter carcasses with impaired meat tenderness. Irrespective of the breed, maternal undernutrition affected meat color and increased the meat content of some healthy fatty acids. In summary, early maternal undernutrition affected the fetal programming of beef male offspring with persistent consequences at slaughter.