Biotechnology Commons^™

Prolonged exposure to high temperature can significantly increase metabolism, depress appetite, reduce meat production and raise mortality in broilers. Because the cardiovascular system plays an important role to dissipate heat and transport oxygen, strong cardiac function is indispensable for birds to survive under heat stress. However, due to small hearts relative to body weight, modern broilers have high risk of heart failure at high temperature.

In this study, a Ross 708 line (modern broilers) and a Heritage broiler line (relaxed selection since the 1950s) were subjected to heat stress at 35℃  for 7 hours/day from 21 to 42 days posthatch …

Increase of fat cells (FCs) in adipose tissue is attributed to proliferation of preadipocytes or immature adipocytes in the early stage, as well as adipogenic differentiation in the later stage of adipose development. Although both events are involved in the FC increase, they are contrary to each other, because the former requires cell cycle activity, whereas the latter requires cell cycle withdrawal. Therefore, appropriate regulation of cell cycle inhibition is critical to adipogenesis. In order to explore the important cell cycle inhibitors and study their expression in adipogenesis, we adopted a strategy combining the Gene Expression Omnibus (GEO) database available …

Background: It is widely known that castration has a significant effect on the accumulation of adipose tissue. microRNAs (miRNAs) are known to be involved in fat deposition and to be regulated by the androgen-induced androgen receptor (AR). However, there is little understanding of the relationship between miRNAs and fat deposition after castration. In this study, the high-throughput SOLiD sequencing approach was used to identify and characterize miRNA expression in backfat from intact and castrated full-sib male 23-week-old pigs. The patterns of adipogenesis and fat deposition were compared between castrated and intact male pigs.

Results: A total of 366 unique miRNA …

Tibetan chicken is one of those chicken breeds that could adapt to high altitude and low oxygen pressure environment; it owes to an integrative genetic mechanism for hypoxia adaptability compared to lowland chicken breeds. HIF-1α and HIF-2α are the central factors playing important roles in maintaining organisms’s oxygen homeostasis. In this study, the expression of HIF-1α and HIF-2α genes were investigated by Real Time-PCR in Tibetan chicken and Dwarf chicken embryo brain tissue under normoxia (21% oxygen concentration) and hypoxia (13% oxygen concentration). The results showed that Tibetan chicken always had lower mortality than Dwarf chicken during the incubation. We …