Thermoregulatory reactions of female buffaloes raised in the sun and in the shade, in the climatic conditions of the rainy season of the Island of Marajó, Pará, Brazil

Abstract

Buffaloes are well-adapted to hot, humid climates and muddy terrain, however they show signs of thermal discomfort when exposed to direct sunlight due to their specific structural features such as dark skin, small number of sweat glands/skin area and thick skin. Epidermis layer of the skin, making heat dissipation difficult. The study aimed to evaluate the thermal comfort of female buffaloes raised in traditional and silvopastoral systems, on the island of Marajó, Pará, during the rainy season of the year. The experiment was carried out in Cachoeira do Arari, Retiro Grande, Marajó, Pará (00°55'37.814424”S 48°43'48.143060”W). Twenty female Murrah buffaloes, aged between 2 and 3years and average weight of 282 ± 29 kg, were used. They were fed on pasture and divided into two groups: WS group (with shade) and NS group (without shade). The WS group (n = 10) remained grazing in a silvopastoral system, with access to the shade of red Jambeiro (Syzygium malaccense) trees. The NS group (n = 10) was kept in grazing, in a traditional system, without access to the shade of trees or shades. The physiological variables rectal temperature (RT), respiratory rate (RR) and body surface temperature (BST) (forehead, left side of the thorax and left flank) were measured at 6:00, 10:00, 14:00, 18:00, and 22:00 h. At the same times, data on air temperature, relative air humidity, wind speed (WSP), solar radiation (SR) and Temperature and Humidity Index (THI) were also recorded. THI, WSP and SR were higher at 14:00 h (P < 0.05). At 10:00, 14:00, and 18:00 h there was difference of RT between treatments (P < 0.05), where animals of the NS group had the highest values. In the NS group, the highest value of RT was observed at 14:00 h (39.38 ± 0.43°C), when THI and SR were higher. At 10:00 and 14:00 h, BST was higher in the NS group (p < 0.05), of 34,55 ± 1.03 and 35.35 ± 1.51°C, respectively, and both groups had the highest value of BST at those same times. There was difference of the RR between treatments at 10:00 h and 14:00 h (p < 0.05), where the highest values were found in the NS group (33.71 ± 7.58 e 50.40 ± 18.41 mov./min., respectively). Even in the rainy season of the year, the climatic conditions of Ilha do Marajó are unfavorable to the welfare of buffaloes, especially at 2:00 pm, when the SR is higher. Thus, the use of the system with access to shade, such as silvopastoral, is recommended, in order to provide greater thermal comfort to animals and improve their productivity.

The effect of birth weight and time of day on the thermal response of newborn water buffalo calves

“…Certain morphological characteristics of the water buffalo, i.e., scarce hair, thick epidermis, high melanin concentration, and the small number and large size of sweat glands, all favor the development of thermoregulatory mechanisms that differ from those commonly observed in conventional cattle (Bos taurus and Bos indicus) (14). Other elements that influence this response are environmental temperatures and the weather, as windy and rainy conditions at the beginning of spring or winter impact the thermoregulation process (15,16).…”

Muscle mineral profile of water buffaloes (Bubalus bubalis) reared in different production systems of the Brazilian Eastern Amazon

“…However, the abundance of water, as often happens in the rainy season of the year in some regions of Brazil, can penalize the mineral content of the soil. In sandy soils, for example, nutrient leaching may occur as a result of heavy rainfall, which will consequently cause forage in pastures to have a low content of minerals available to incorporate, which will affect the entire food chain (24,25).…”

Animal welfare and effects of per-female stress on male and cattle reproduction—A review

“…Several studies have been carried out to measure the effects resulting from microclimates that interfere with the thermal comfort of cattle, the main variables being measurable; temperature, humidity, wind speed and solar radiation that are used to determine the indices of thermal comfort in animals (7)(8)(9)(10)(11)(12)(13).…”