Effects of transport and altitude on hormones and oxidative stress parameters in sheep

Effects of dietary rumen-protected glucose level and taurine supplementation on weight change and oxidative stress state of yaks after transport

Rumen-protected glucose (RPG) and taurine (TAU) are crucial for the nutrition and physiology of ruminants, enhancing production performance and mitigating negative energy balance. This study aimed to assess the impact of RPG levels and TAU supplementation on the body weight, antioxidant capacity, immune function and stress responses in yaks before and after transport. Thirty-two healthy male yaks, aged 3 years and weighing 172.5 ± 10.2 kg, were randomly assigned to one of four dietary treatments: (1) low RPG and low TAU (LRLT), with 1% RPG and 5 g/d TAU; (2) low RPG and high TAU (LRHT), with 1% RPG and 15 g/d TAU; (3) high RPG and low TAU (HRLT), with 3% RPG and 5 g/d TAU; and (4) high RPG and high TAU (HRHT), with 3% RPG and 15 g/d TAU. The yaks were treated with the corresponding diet for 7 days, then received 9 h of transportation, and finally fed the same diet at their destination for 30 days. The weight was measured before and on days 0 and 30 after transport, and the plasma was collected before and on day 0, 10, and 30 after transport for analysis of biochemical, antioxidant, immune, and stress response indicators. We observed that transport increased plasma concentrations of total cholesterol, total protein, lactate dehydrogenase, creatine kinase, malondialdehyde, cortisol and lipopolysaccharides of yaks among treatments, while decreased their BW and plasma IL-10 concentration. Increasing TAU supplementation reduced weight loss (8.42 vs. 11.9 kg) and weight loss percent (4.83% vs. 6.87%) in yaks after transport. The concentration of MDA in plasma was lower in HRHT than in LRLT at day 0 after transport (p = 0.03). The activity of GSH-PX was higher in HRHT than in LRLT at day 10 after transport (p = 0.04). Concentrations of IL-10 at day 0 and 10 after transport was higher in HRHT than in LRLT and HRLT (p = 0.02, p = 0.01, respectively). With the increase of TAU supplementation, concentrations of IL-1β at day 30 after transport (p = 0.02), TNF-α at day 0 after transport (p = 0.02), COR at day 10 (p = 0.03) and 30 (p = 0.05) after transport as well as LPS at day 0 after transport (p = 0.04) decreased. In addition, concentrations of COR at day 0 after transport was lower in LRHT and HRHT than in LRLT (p = 0.03). Based on all the results, we demonstrated that increasing TAU supplementation levels reduced post-transport weight loss in yaks, improved their antioxidant capacity and immune function, and alleviated stress responses. Considering the effect of resistance to transport stress and costs, the optimal treatment identified in this study involved a diet containing 1% RPG and supplemented with 15 g/d TAU.

Dietary Supplementation of Mixed Organic Acids Improves Growth Performance, Immunity, and Antioxidant Capacity and Maintains the Intestinal Barrier of Ira Rabbits

The aim of this study was to investigate the effects of mixed organic acids (MOAs) on growth performance, immunity, antioxidants, intestinal digestion, and barrier function in Ira rabbits. A total of 192 weaned male Ira rabbits at 35 days of age were randomly assigned to four groups with six replicates of eight rabbits each. The rabbits in the control group (CON) were fed a basal diet, and the antibiotic group (SAL) was fed a basal diet supplemented with 60 mg/kg salinomycin. The test groups were fed a basal diet supplemented with 1000 mg/kg and 2000 mg/kg MOAs (MOA1 and MOA2, respectively). The experiment lasted for 55 days. The results showed that the ADG of Ira rabbits in the SAL group and MOA1 group was higher than that in the CON group (p < 0.05). The serum IL-6 and liver MDA levels of Ira rabbits in the SAL group, MOA1 group, and MOA2 group were lower than those in the CON group (p < 0.05). In addition, sIgA levels in the jejunal mucosa of Ira rabbits in the SAL group and MOA1 group were increased compared with those in the CON group (p < 0.05). Compared with the CON group, the gene expression of IL-6 was decreased (p < 0.05) in the jejunal mucosa of Ira rabbits in the SAL, MOA1, and MOA2 groups, while the gene expression of IL-1β tended to decrease (p = 0.077) and the IL-10 content tended to increase (p = 0.062). Moreover, the gene expression of ZO-1 in the jejunal mucosa of Ira rabbits was elevated in the MOA1 group compared with the CON group (p < 0.05). In conclusion, dietary supplementation with MOAs can improve growth performance, enhance immune function and antioxidant capacity, and maintain the intestinal barrier in weaned Ira rabbits.

Stress Factors and Their Effects on Productivity in Sheep

Products obtained from sheep have an economically important place in the world. Their adaptability to different climatic conditions, their ease of care and feeding, their high utilization of poor pasture areas with low yield and quality, the ease of flock management, their high twinning rate, and their short intergenerational period are some of the advantages of sheep production. Sheep production has the ability to adapt better to environmental stress factors, as can be understood from the presence of sheep in different geographical regions at a global level. However, the changes in environmental conditions and production cause some negative results in animals. All these negative results expose animals to various stress factors (heat, cold, transport, treatment, nutritional, shearing, weaning, etc.). All stress factors that directly and indirectly affect sheep production ultimately lead to compromised performance, decreased productivity, increased mortality, and adverse effects on the immune system. In order to cope with the current stress parameters in animals and to achieve optimum production, a holistic approach is needed according to the environmental conditions and available resources. It is important to consider the factors involved in these responses in order to manage these processes correctly and to develop adequate strategies and improve sheep welfare. This review aimed to reveal the importance of some stress factors in sheep and their effects on sheep productivity.

An Overview on Assay Methods to Quantify ROS and Enzymatic Antioxidants in Erythrocytes and Spermatozoa of Small Domestic Ruminants

The present review aims to provide an overview of the assay methods for the quantification of ROS and principal enzymatic antioxidants as biomarkers of oxidative stress in erythrocytes and spermatozoa of small domestic ruminants. A complete literature search was carried out in PubMed, Scopus and the World Wide Web using relevant keywords and focusing on the last five years (2018-2023). Among spectrophotometry, fluorometry and chemiluminescence, the most widely used method for ROS assay is fluorometry, probably because it allows to simultaneously assay several ROS, using different probes, with greater economic advantages. Regarding intracellular antioxidant enzymes, recent literature reports only spectrophotometric methods, many of which use commercial kits. The use of a less sensitive but cheapest method is suitable because both erythrocytes and spermatozoa samples are highly concentrated in domestic ruminant species. All methods considered in this review have been found to be appropriate; in general, the differences are related to their costs and sensitivity. Quantification of ROS and enzymatic antioxidant activity in erythrocytes and spermatozoa may find application in the study of the welfare and health status of small domestic ruminants for monitoring livestock production.

Features of the functional state of the organism of sheep under stress

The stresses that arise during routine animal husbandry procedures, such as milking, shearing, weighing, loading and hoof care, are an actual problem in animal husbandry. The components of economic damage under stress are a decrease in overall resistance and productivity, deterioration in product quality, an increase in labor costs and funds per unit of production, an increase in animal morbidity and mortality. The studies were carried out on the basis of Belozernoe farm in the Salsky district, the Rostov region. A complex of clinical and laboratory studies was performed on 18 sheep (10 Romanov and 8 Tsigay breeds) aged 2 to 3 years, before and after a planned routine shearing. Stress in sheep caused by planned shearing was clinically manifested by general depression, in some cases, subfebrile fever, moderate tachypnea and tachycardia. It was shown that stress was accompanied by anemia, the development of erythropenia and leukopenia. Immunocompetent cells in the blood of experimental animals during stress development were analyzed. Severe lymphocytopenia was found to occur after a haircut. In addition, in the blood of experimental animals under stress, a tendency to a decrease in T-total cells was noted, which was accompanied by an increase in 0-cells, which was significant in sheep of the Tsigay breed (p0.05). When analyzing the main immunoregulatory T cells in sheep under stress, a significant increase in T-suppressors was revealed with a relatively stable level of T-helpers in the blood studied. Thus, a significant (p0.05) increase in the level of T-suppressors in sheep of Romanov and Tsigay breeds was recorded; it was by 1.15 and 1.19 times higher compared with the initial data. It should be noted that we did not find any significant differences between animals of Romanov and Tsigay breeds in stress development after shearing. The obtained data should be taken into account in the further search for methods of stress correction in sheep.