In the sweltering heat of a summer day, chickens, unlike humans, can’t simply turn on the air conditioning or grab a cold drink. They are, after all, covered in feathers and lack sweat glands, making them particularly vulnerable to thermal stress. But what if there was a breed of chicken that could withstand the heat better than others? This is precisely what a team of researchers, led by Guo Li from the College of Coastal Agricultural Sciences at Guangdong Ocean University, set out to investigate.
Their study, recently published in Poultry Science, focuses on a novel dwarf chicken strain with frizzled feathers, aptly named dwarf chicken with frizzled feather (DFC). The researchers found that these chickens, with their unique physical characteristics, might hold the key to more resilient poultry farming in hot climates.
The study began by analyzing the growth patterns of DFCs using three different mathematical models. The Gompertz model emerged as the best fit for predicting the body weight of these chickens. But the real test came when the researchers subjected the chickens to heat stress (HS) conditions. For two weeks, the HS group was exposed to temperatures of 34 ± 1°C for eight hours a day, mimicking the harsh conditions that poultry farmers in hot regions often face.
The results were striking. The integrity of muscle, liver, spleen, and small intestine tissues was affected under HS conditions. “The length of the ileum was significantly decreased,” Li noted, “and the thigh muscle development factor MYOD1 expression was down-regulated, while the expression of MSTN was up-regulated.” This suggests that heat stress impacts muscle development and overall growth.
However, the story doesn’t end there. The researchers also found that the expression of appetite-promoting factors like AMPKα-1 and AGRP in the gut-brain axis were down-regulated, while appetite-restrain factors like CCK, GHRL, and CART were significantly up-regulated. This indicates that heat stress primarily affects the appetite of chickens, rather than their ability to absorb nutrients.
Li explained, “The intestinal transport and absorption factors ZO1, OCLN, PepT1, SGLT1, and CAT1 were up-regulated, and GLUT1 was down-regulated. These results indicated that HS mainly impacted the appetite of chickens and did not significantly disrupt the nutrient absorption function of these chickens.” This is a crucial finding for the poultry industry, as it suggests that DFCs could be more tolerant to hot environments due to their frizzled feathers, small body size, and low basal metabolic rate.
The implications of this research are vast, particularly for the energy sector. As global temperatures rise, the demand for energy-efficient cooling solutions in poultry farming will only increase. DFCs, with their inherent heat tolerance, could reduce the need for excessive cooling, leading to significant energy savings and lower carbon emissions.
Moreover, the findings could shape future developments in poultry breeding and genetics. By understanding the genetic mechanisms behind heat tolerance in DFCs, researchers could potentially develop new breeds that are better equipped to handle thermal stress. This could revolutionize poultry farming in hot regions, making it more sustainable and resilient in the face of climate change.
The study, published in Poultry Science, opens up exciting possibilities for the future of poultry farming. As Li and his team continue to unravel the mysteries of DFCs, one thing is clear: these unique chickens could play a pivotal role in shaping a more sustainable and energy-efficient future for the poultry industry.