The synergistic effect of traditional Chinese medicine prescription and rumen-protected γ-aminobutyric acid on beef cattle under heat stress

The effects of gamma-aminobutyric acid on growth performance, diarrhoea, ruminal fermentation, and antioxidant capacity in pre-weaned calves

The pre-weaning phase is a vital period for the growth and development of calves, significantly impacting their future health and productivity. Gamma-aminobutyric acid (GABA) is an inhibitory neurotransmitter in the mammalian central nervous system that lowers blood pressure, stimulates feed intake, and enhances antioxidant capability. Gamma-aminobutyric acid has been proven beneficial for adult cows, while little research has been conducted on calves. Therefore, this study examined the effects of GABA on growth performance, diarrhoea, ruminal fermentation, and antioxidant capacity in pre-weaned Holstein calves. Ninety male Holstein calves were allocated to five groups: 0 mg/d (G0), 25 mg/d (G25), 50 mg/d (G50), 100 mg/d (G100), and 200 mg/d (G200). The experiment was conducted from 11 to 75 days of calves age, and the calves were weaned at 75 days of age. Growth performance indicators, ruminal fluid, faecal score, and serum were collected at 11, 28, 42, 60, and 75 days of calves' age. The results showed that adding GABA positively affected average daily gain and body height, with no effects on diarrhoea frequency. All dosages significantly reduced acetate and total volatile fatty acid levels in ruminal fermentation, with butyrate showing a complex response at higher doses. Overall, we recommended 100 mg/d as the optimal GABA supplementation level to improve growth performance and regulate the ruminal fermentation of pre-weaned calves before weaning.

The Protective Role of Heat Shock Proteins against Stresses in Animal Breeding

Heat shock proteins (HSPs) play an important role in all living organisms under stress conditions by acting as molecular chaperones. The expression of different HSPs during stress varies depending on their protective functions and anti-apoptotic activities. The application of HSPs improves the efficiency and decreases the economic cost of animal breeding. By upregulating the expression of HSPs, feed supplements can improve stress tolerance in farm animals. In addition, high expression of HSPs is often a feature of tumor cells, and inhibiting the expression of HSPs is a promising novel method for killing these cells and treating cancers. In the present review, the findings of previous research on the application of HSPs in animal breeding and veterinary medicine are summarized, and the knowledge of the actions of HSPs in animals is briefly discussed.

Effects of rumen-protective γ-aminobutyric acid additive on lactation performance and serum biochemistry in heat-stressed cows

In the context of global warming, heat stress has become one of the major stress factors limiting dairy cattle production. Although many methods have been explored to help cows mitigate the negative effects of heat stress during the hot summer months, maintaining the performance of high-yielding cows under heat stress is still a great challenge. The aim of this trial was to investigate the effect of RP-GABA in the diet on milk yield, milk composition and serum biochemical parameters in heat-stressed cows. Twenty Chinese Holstein cows in early lactation (51.00 ± 4.92 kg milk/d, 71 ± 10.94 d in milk and 2.68 ± 0.73 parities) were included in this experiment and randomly divided into four groups (n = 5/group). The four experimental groups consisted of one control group (0 g RP-GABA/d) and three treatment groups, given 5, 7.5 and 10 g RP-GABA/d of dry matter (DM) per cow, respectively. The results showed that supplementing high-yielding cows with 10 g/d of RP-GABA improved milk protein production but had no effect on the improvement of other production performance, the alleviation of heat stress in cows, or the improvement of immune function and antioxidant capacity. Ultimately, we conclude that the supplementation of 10 g/d RP-GABA to heat-stressed, high-yielding dairy cows can provide a degree of performance enhancement. Furthermore, our study provides some reference for nutritional improvement measures for summer heat stress in dairy cows, especially high-yielding cows.

Recent advances in feed and nutrition of beef cattle in China - A review

The beef cattle industry in China has advanced remarkably since its reform and opening up; consequently, China has become the world's third-largest beef cattle producer. China is also one of the countries with the most substantial research input and output in the field of beef cattle feed and nutrition. The progress and innovation by China in the research field of beef cattle feed and nutrition have undoubtedly promoted the development of the domestic beef cattle industry. This review summarizes recent advances in feed resource development, nutrient requirements, and nutritional regulation of beef cattle in China. Limitations in current research and perspectives on future work are also discussed.

Maternal Dietary Supplementation with γ-Aminobutyric Acid Alleviated Oxidative Stress in Gestating Sows and Their Offspring by Regulating GABRP

Sows usually suffer oxidative stress during gestation, and this limits the growth of fetuses via placenta. Gamma-aminobutyric acid (GABA) is a functional nonessential amino acid engaged in regulating the physiological status of animals. However, the effects of GABA on the oxidative homeostasis of sows and their offspring remain unclear. Eighteen late gestating sows (85 d) were divided into the CON and GABA groups and fed the basal diet and the GABA diet (200 mg/kg GABA), respectively, until farrowing. At parturition, the sows’ litter characteristics, the plasma antioxidant parameters of sows, and their offspring were evaluated. The results showed that GABA supplementation had no marked effect on the reproductive performance of sows (p > 0.10) but had a trend of reducing the amount of intrauterine growth restriction (IUGR) in piglets (0.05 < p < 0.10). At the same time, the addition of GABA elevated the plasma superoxide dismutase (SOD) level of sows and enhanced the glutathione peroxidase (GSH-Px) activity of newborn piglets (p < 0.05). Based on the H2O2-induced oxidative stress in pTr-2 cells, GABA elevated intracellular GSH-Px, SOD, catalase (CAT), and total antioxidant capacity (T-AOC, p < 0.01) and upregulated the gene expressions of CAT, gamma-aminobutyric acid receptor (GABRP), and nuclear factor-erythroid 2-related factor-2 (Nrf2) in H2O2-treated pTr-2 cells (p < 0.05). Taken together, GABA improved the antioxidant capacity of sows and alleviated the placental oxidative stress by upregulating the GABRP and Nrf2 genes, which have the potential to promote oxidative homeostasis in newborn piglets.