Vitamins A and E in Carcass Fat from Japanese Black and F1 Cross Cattle

An Assessment of Stress Status in Fattening Steers by Monitoring Heart Rate Variability: A Case of Dietary Vitamin A Restriction

Heart rate variability (HRV), heart beat-to-beat variations, is a measure of cardiac autonomic functions, and HRV monitoring using sensor technology can be a non-invasive way to assess stress of animals. The objective of this study was to investigate the effect of dietary vitamin A (VA) restriction to enhance beef quality on the physiological status of fattening steers by HRV analysis. Six Japanese Black steers were equally allocated into VA-restricted (RES) and VA-supplemented (SUP) groups. The RES steers were fed VA-restricted diets from 11 to 20 months of age. The inter-beat intervals and blood VA concentration were measured at 18 and 24 months of age. HRV parameters in time, frequency, and non-linear domains were calculated using the inter-beat intervals. Blood VA concentration was significantly lower in RES steers than in SUP steers at 18 months of age (P < 0.05) but did not differ between the groups at 24 months of age. The HRV analysis indicated greater sympathetic and lower parasympathetic activities in RES steers than in SUP steers (P < 0.05). However, there were significant interactions of the group and age on HRV parameters (P < 0.05), indicating that although RES steers at 18 months of age might suffer from slight stress, the response could recover to a level similar to SUP steers at 24 months of age by the increase in blood VA concentration.

Rearing characteristics of fattening Hanwoo steers managed in different stocking densities

Objective

This study was conducted to analyze the effects of stocking density on growth and carcass quality, and behavior of Hanwoo cattle to conform with global trends, targeting animal welfare production through the practice of environmentally friendly condition.

Methods

Thirty six steers were randomly assigned to three treatment groups (C: 5 heads, T1: 4 heads, T2: 3 heads) and reared in separate pens with a constant stocking density of 50 m² (C: 10 m²/head, T1: 12.5 m²/head, T2: 16.67 m²/head) per group from 12 to 30 month of age. Growth performance, behavior and carcass quality traits of each steer were recorded and compared between the treatment groups.

Results

In general, the average daily gain during the fattening period was lower in group T2 than in T1 and the control groups. However, carcass weight and dressing percentage was lower in the control group than in T1 or T2 groups (p<0.05). Also, marbling score at 30 months of age was the lowest in the control group (p<0.05), while the three heads group (T2) had the greatest longissimus muscle area and marbling score (p<0.05). The behavior of walking time was the greatest in T2 group, while self-grooming and fighting occurred with the most frequency in the control group (p<0.05).

Conclusion

Our results show that the steers in more spacious stocking density had better carcass quality and wellbeing related behaviors, indicating that a lower density has a positive effect on raising management and carcass quality. Thus it is a need to install appropriate pens fitted to welfare-oriented management practices from growing to fattening period in Hanwoo cattle.

Surveillance of diarrhea-causing pathogens in dairy and beef cows in Yamagata Prefecture, Japan from 2002 to 2011

The economic consequences of bovine diarrhea are serious. Few long‐term epidemiological data are available concerning the causative pathogens of bovine diarrhea in Japan. From 2002 to 2011, surveillance of enteric pathogens was performed in cows of various breed and age from 302 farms in which diarrhea had occurred in Yamagata Prefecture, Japan. Differences between dairy and beef cows in the number of cases of diarrhea and rates of infection by Salmonella spp. and Eimeria spp. were found. Clinical symptoms (duration of epidemic, hematochezia and complications) caused by bovine rotavirus infection were milder than those caused by bovine coronavirus infection.

Plasma 8-isoprostane concentrations and adipogenic and adipokine gene expression patterns in subcutaneous and mesenteric adipose tissues of fattening Wagyu cattle

We hypothesized that fattening Wagyu cattle fed conventional low-vitamin fattening diets are exposed to oxidative stress. In this experiment, we studied the plasma concentrations of 8-isoprostane and the fat depot-specific effects of the diet-induced adipogenic (C/EBPβ, C/EBPδ, C/EBPα and PPARγ2) and adipokine (VEGF, FGF-2, leptin and adiponectin) gene expressions in fattening Wagyu steers. Animals were fed a high-vitamin (α-tocopherol and β-carotene) diet (HV) or a control diet (CT) during the fattening period (from 10 to 30 months of age). The plasma concentrations of 8-isoprostane, a marker of oxidative stress, were significantly lower in the HV group than in the CT group. In mesenteric adipose tissue, the expressions of the adipogenic and adipokine genes in the HV group were significantly lower than those in the CT group. In contrast, there were no differences in the expression of the adipogenic and adipokine genes in subcutaneous adipose tissue between groups. These results suggest that higher intake of dietary α-tocopherol and β-carotene affects the expression patterns of adipogenic and adipokine genes in a fat depot-specific manner with the reduction of plasma 8-isoprostane concentrations.