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The aim of the study was to evaluate the effect of water restriction and low- and high-energy diets on sheep's thermoregulatory responses and ingestive behavior. Forty sheep, non-castrated, with an average body weight of 18.85 kg (SD = 2.80 kg) and an average age of 5 months were assigned to a 2 × 2 factorial arrangement, comprising 2 diets (high- and low-energy) and 2 water offers (ad libitum and 50% water restriction), with 10 replicates. Thermoregulatory responses were evaluated in two periods (morning and afternoon). There was an interaction effect of Diet x Water supply x Periods on respiratory rate (P < 0.05). High-energy diets resulted in increased heart rate, idleness, dry matter feeding and rumination efficiency, and water intake. Low-energy diets increased feeding time, rumination time, the number of ruminal cuds, chews per day, total chewing time, neutral detergent fiber intake and rumination efficiency, number of ruminations per day, average duration of rumination, and defecation frequency. Water supply affected heart rate and idleness (P < 0.05). Sheep had higher values of heart rate and rectal and surface temperatures during the afternoon (P < 0.05). Water restriction combined with a low-energy diet and high environmental temperature leads to a reduction in the respiratory rate of Santa Inês crossbred sheep. Regardless of the dietary energy value, water restriction by 50% of the daily requirement of sheep reduces dry matter intake and increases idleness.

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The aim of this study was to evaluate the biochemical, hormonal, and hematological blood responses of native sheep subjected to five temperatures (20°, 24°, 28°, 32°, and 36 °C), using 24 sheep of the following breeds: Santa Inês (SI), Morada Nova (MN), Soinga (SO) and no defined racial pattern (NDRP), kept in collective pens inside the climatic chamber. The experimental design was completely randomized, in a 5 × 4 factorial scheme (5 temperatures and 4 breeds) with 6 animals of each breed at each temperature. There was interaction for urea (P < .0001), glucose (P < .0001), cholesterol (P < .0001), and magnesium (P < .0001) as a function of breed and air temperature. Urea (P = .001), glucose (P < .0001), triglycerides (P = .033), cholesterol (P = .004), and magnesium (P < .0001) showed differences according to breed. It was observed that T4 (P < .0001) and cortisol (P < .0001) showed an interaction between breed and temperature, while T4 (P = .001) and cortisol (P = .001) an effect of breed. The highest magnesium concentration was observed in MN, and the lowest was in NDRP, SO, and SI, which are statistically similar, and SI and NDRP are statistically similar. The hormones showed a significant effect (P < .0001) for temperature, where cortisol increased, and thyroid hormones decreased with increasing temperature. Temperatures of 32° and 36 °C contribute to changes in blood, hormone, and hematological biochemical responses of native sheep.

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The objective of this research was to evaluate the thermal exchanges, physiological responses, productive performance and carcass yield of Guinea Fowl confined under thermoneutral conditions and under thermal stress. For the experiment, 96 animals were confined in 8 experimental boxes of 1 m2 of area, each, divided in equal numbers and placed inside two distinct climatic chambers, where the birds were distributed in a completely randomized design, with two treatments (air temperatures of 26 and 32 °C, respectively). For the collection of physiological responses and carcass yield 16 birds were evaluated and for the collection of data on feed and water consumption and productive responses, 48 birds per treatment were evaluated. The environmental variables (air temperature (AT), air relative humidity and wind speed), temperature and humidity index (THI), heat exchanges, physiological responses (respiratory rate, surface temperature, cloacal temperature and eyeball temperature), feed (FC) and water (WC) consumption and production responses (weight gain, feed conversion index and carcass yield) of the birds were evaluated. With the elevation of the AT, it could be noticed that the THI went from a thermal comfort condition to an emergency condition, where the birds lost part of their feathers, increased all physiological responses evaluated, and consequently, reduced by 53.5% the amount of heat dissipated in the sensible form and increased by 82.7% the heat losses in the latent form, increasing also the WC. ATs of up to 32 °C did not significantly affect the productive performance and carcass yield of the guinea fowl.

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Aviculture is a developed and important industry worldwide. However, it is an industry that produces solid waste such as bedding. As an attempt to reduce environmental impact and productive activity costs, beds are reused by several consecutive lots which can increase microorganism concentration and lead to unsanitary conditions. In this regard, it is essential to adopt a litter pre-treatment during the gap sanitary period between lots to avoid passing problems to the birds from the current flock to the subsequent flock and to guarantee the litter quality. Several factors must be considered to guarantee that there is minimal damage to chicken production. Therefore, this literature review aims to approach the main factors that affect the thermal comfort and chicken litter quality, as well as alternatives used as an alternative biological treatment to guarantee its reuse quality.

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The structure of the coat and integument of small ruminants reared in semi-arid regions have valuable characteristics that favor their adaptation to the region. The objective of this study was to evaluate the structural characteristics of the coat and integument and sweating capacity of goats and sheep in the Brazilian semi-arid region, using 20 animals, 10 of each breed, 5 males and 5 females of each species, grouped in a completely randomized design in a 2 x 2 factorial scheme (2 species and 2 genders) with 5 replicates. The animals were already being kept under the influence of high temperatures and levels of direct solar radiation before the day of the collections. At the time of the evaluations, ambient temperature was high, with low relative humidity. The pattern of epidermal thickness and sweat glands per body region was superior in sheep (P < 0.05), and the number of hair follicles and sweat rate were similar (P > 0.05) between the species. There was no difference (P > 0.05) in the evaluated characteristics between the genders, showing that they are not influenced by hormones. The morphology of the coat and skin of these animals showed a superiority of goats compared to sheep.

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This work aimed to perform bioclimatic zoning based on the temperature and humidity index (THI) for quails from the 3rd to the 5th week of life during the rainy season in the state of Paraíba, Brazil, in order to identify the most suitable mesoregions among the Zona da Mata, Agreste, Borborema and Sertão for the breeding of these birds and to propose mitigating measures for the thermal comfort of the animals. The monthly air temperature and relative humidity data for calculating the THI were obtained from conventional meteorological stations of the National Meteorological Institute of the Brazilian federal government from 1961 to 2015, in turn making maps with the spatial distribution of the index. The index ranged from 71 to 76 in the various mesoregions of Paraíba, with Agreste being the best mesoregion for breeding quails from the 3rd to the 5th week of life, thus providing a thermal comfort zone for birds and only requiring a few corrective measures in their facilities, when necessary, followed by the Sertão, Zona da Mata and Borborema mesoregions.

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The objective of this study was to evaluate the productive performance and carcass characteristics of confined Santa Inêssheep, fed different diets, in a Semiarid environment. Twenty whole sheep with 5 ± 0.5 months of age and 27 ± 2.0 kg were used, receiving two different diets for 72 experimental days, one composed of defatted soybean meal and the other of protein-enrichedcactus meal. They were evaluated for different diets, consumption, production, carcass characteristics, morphometric measures and edible components. The experimental design was in randomized blocks with two treatments and 10 replications. Performance dataand carcass characteristics were evaluated by analysis of variance and means compared by t test at 5% probability level using Statistical Analysis System [SAS]®(1999). Thus, the use of emulsified palm forage protein in the feeding of Santa Inês male lambs proved to be an excellent protein source when compared to the use of defatted soybean meal, since the results of performance and carcass characteristics were similar, being the use of this alternative source advised as it presents the best benefit-cost ratio.(AU)

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The Brazilian Amazon region is characterized by high rainfall, with high temperatures and relative humidity, where sheep are raised in extensive and semi-intensive systems and some regions. This work aimed to evaluate the climatic indices of sheepfolds in the Amazon region, the productive performance, and physiological variables of Santa Inês sheep confined in sheepfolds with fiber cement (FC) and polyvinyl chloride (PC) tiles. Twenty castrated males of Santa Inês sheep were used, with a mean age of 1.5±0.2 years old and a live weight of 23±2.1 kg. The statistical design used was a completely randomized design with two roofs (FC and PC). The temperature, relative humidity of the air, temperature index of the black globe, and thermal radiation load was above the comfort zone for sheep, being higher (P < 0.05) in the sheepfold with PVC tile than FC, which contributed to the increase in respiratory rate, as a way to maintain the animals' homeotherm. Furthermore, sheep installed in the sheepfold with FC tile showed the highest weight gain, spent more time feeding, increased feeding efficiency, dry matter and fiber intake, reducing daily water intake.

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This study systematically collected data on variables that influence the thermal environment characteristics in poultry houses. Laying poultry farming is a relevant economic activity in Brazilian agriculture and has been expressively growing mainly regarding genetics and nutrition. Thermal comfort in poultry houses is needed to achieve poultry's maximum productive potential. Therefore, laying aviaries previously naturally ventilated (positive pressure) are starting to be equipped with cage batteries and designed with lateral closures, using negative pressure ventilation and in some cases associated with adiabatic cooling. However, negative pressure ventilation systems' thermal efficiency in tunnel mode and its distribution in different cage levels is still slightly known. Consequently, this system's thermal efficiency needs to be investigated to ensure adequate climate indices recommendations and avoid costs and losses due to inadequate handling and facilities.

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he objective was to evaluate the effect of the season on the sexual behavior patterns adopted by Morada Nova sheep in the Brazilian semiarid region. A total of 55 and 59 female sheep were used in the rainy and dry seasons, respectively, attended by four males of the same breed in rotation. The females identified in oestrus were released in a pasture, together with the breeder of the day for each season, and aspects of sexual behavior were measured for an uninterrupted period of 11 hours/day. Assuming a negative binomial distribution, the behavioral frequencies were subjected to deviation analysis and compared using the chi-square. Heading in the male was observed more frequently during the rainy season (0.12) and shifts with higher temperatures; the turn of the head in relation to the man was observed more frequently during the dry season (2.49). The interactions between seasons and shifts significantly affected the following behaviors: sniffing the male, sniffing the male's urogenital region, wagging the tail, lifting the tail, and urinating. Behavioral variables were influenced by the season. Morada Nova sheep reduce their water intake and grazing time to engage more efficiently in reproductive activities, thus demonstrating an ability to adapt to the Caatinga.(AU)

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