Resumo
In tropical and subtropical regions animals suffer pronounced heat stress effect on reproductive function, being one of the most noticeable effects the reduction of conception rate. When evaluating animals heat stress, rectal temperature measurement is important tool because indicates heat release mechanisms became insufficient to maintain homeothermy. This study aimed to evaluate body temperature at fixed time artificial insemination of crossbred dairy cows and their conception at 30 days pregnacy. Experiment was performed from April 26, 2010 to January 28, 2012 at Estação Experimental Glória of Universidade Federal de Uberlândia, at Triângulo Mineiro, Brazil. One hundred-twelve crossbred dairy cows and heifers were used. At the moment of insemination, animals were housed in shaded pen and body temperature was collect using clinical thermometer introduced in rectal mucosa. Environmental variables collect were air temperature, maximum temperature, minimum temperature and relative humidity. Data were analyzed in two different periods: from April to September (mild weather-MW) and from October to March (hot weather-HW). The statistical model included the effect of category, period, pregnancy diagnosis and their interactions, comparing means by Tukeys test, with a significance level of 5%. Means and standard deviations of air temperature, maximum temperature, minimum temperature
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Resumo
Cattle, when in heat stress, deflect energy to increase dissipation to environment, compromising productivity. Thus, in dairy production system it is important to maintain thermal comfort to ensure homeothermy and full performance. One of the physiological measures to evaluate thermal comfort of domestic animals is hair coat surface temperature. Knowing this temperature allows the understanding whether animal performs thermal exchanges by convection through the activation of heat dissipation latent mechanisms. This study aimed to evaluate body surface temperature in crossbred dairy cows on Triângulo Mineiro climatic conditions. This was carried out at Estação Experimental Glória of Universidade Federal de Uberlândia using 53 lactating crossbred cows. Cows were housed in shaded pen for artificial insemination and after it was performed body surface temperature mensurements. Temperature was measured from body surface at four different regions: forehead, withers, groin and hock using an Instruterm infrared thermometer model TI-890. The statistical model used the region to test the effect of surface temperature comparing means by Tukeys test, with a significance level of 5%. Means and standard deviations of ambient temperature, maximum temperature, minimum temperature and relative humidity were respectively 23.96 ± 2.57C; 29.43 ± 2.50C; 17.54 ± 2.38C; and 67.18 ± 15.39%. Temper
O artigo não apresenta resumo em português.
Resumo
To analyze stress during the intermediate stage of gestation, 43 multiparous, crossbred Santa Inês, pregnant ewes, with a average age of 5 and average body weight (BW) of 60kg, were challenged with a intravenous administration of 0.8µg.kg-1 of LPS (lipopolysaccharide E. coli - outer membrane cell of gram-negative bacteria), diluted in physiological saline solution - simulating an immune stressor. The females were placed in individual cages at feedlot, with adaptation period of 5 days before the begin of sampling, with free access to good water quality, shade and food in the trough (corn silage and mineral supplementation). The ewes were divided into three groups, with a completely randomized design (CRD): CG - control group, with 15 animals that were not subjected to stress; IG - intermediate group stage, with 14 animals undergoing stress at 70 days of gestation; FG final group, made up of 14 animals undergoing stress at 120 days of gestation. The variables used to investigate stress were measured during the intermediate stages of pregnancy in a 24 hour sampling, with this was possible to observe the change in rectal temperature (RT) and blood levels of cortisol by its circadian rhythm. Shortly after the baseline sampling, the treatment corresponding to the intermediate stage of gestation was submitted to stress, with the sampling interval of one hour each, from the first to
O artigo não apresenta resumo em português.
Resumo
It is evident the necessity of a better understanding regarding the influence of warmth on the performance of horses in training, establishing that an efficient thermoregulation is essential to provide the physiological demands resulting from effort required and the climatic variables which the animal is exposed. This study aimed to evaluate thermoregulation in horses subjected to 30 minutes of exercise during three periods of the day with different air temperatures and to compare two techniques for measuring the sweating rate (SR) and trans epidermal water loss (TEWL). Three castrated crossbred horses were submitted to a series of half an hour of exercise at different moments (07:00, 13:00, 16:00 hours), carried out as follows: 3 minutes walking, 3 minutes of canter, 10 minutes of trot, 10 minutes of canter, 2 minutes of trot and 2 minutes of canter. Relative humidity, black globe and air temperature were 50%, 34Cº and 20.8ºC; 62%, 35ºC and 28.8Cº; 48%, 34.5Cº and 27.4Cº; respectively for the three periods. Rectal temperature (RT), respiratory rate (RR), body surface temperature (BST), SR through the methodology of Schleger and Turner (1965) and TEWL measured by VapoMeter (Delfin, Finland) were taken before and after exercise. Model for analysis of variance included fixed effects of time and moments, and the means were compared by Tukey test or T at 5% of significance. Signifi
O artigo não apresenta resumo em português.
Resumo
The stress in animals is linked with possible unusual changes that reduce the individual welfare. These changes generally related to the environment or to animal physiology cause imbalance in the biological reactions as a defense by releasing certain substances, including cortisol. There are few studies which indicate that there is heritable consequences promoted by cortisol generated by stress during pregnancy on the first hours of life of the lamb and the gestational phase (days of gestation) in which stress was promoted also interferes with it. Thus, the aim of this study was to evaluate during the delivery time the cortisol levels of lambs and sheep subjected to stress in different weeks of pregnancy and the effect on the birth weight of the lambs. The study was approved by Ethics Committee of FZEA/USP (13.1.2109.74.8). Forty crossbred Santa Ines ewes, multiparous, with an average age of 5 years and 60 kg of body weight (BW), grazing on Coast-cross were used (Cynodon dactylon (L.) Pers.) on rotated system, with free access to shade, water and mineral supplementation. All experimental ewes were artificially inseminated with semen from White Dorper breed. During gestation, the ewes were divided into three groups on a completely randomized design: CG - control group of 15 animals that were not subjected to stress; GI - intermediate group of 12 animals that suffered stress at 7
O artigo não apresenta resumo em português.
Resumo
The work aims to analize the behavior response and the ability to cope stressors when the piglets are exposed to aggressive treatment during the lactation phase. The behavior of 40 piglets was observed from birth to weaning (28 days). In the first fifteen days the observations were done every three days, with an interval of another three days. After this period, the observations were done once a week. Over a period of three hours, every five minutes it was registered the animal behavior. The group was divided into two treatments: rational group, where 18 piglets had minimal interaction with people and it was permitted the routine practice without sudden movements and loud sounds; and the aversive treatment, where 22 piglets received the daily routine of the farm, however, on every half hour during observations the observer performed a direct threat to the sow going into the cage with a flag and abruptly approach the animal, shouting or clapping. To avoid visual contact with the observer, he was located behind the maternity cage. Analysis of variance with fixed effects of time and time and means were compared by Tukey test or T at 5% of significance. In aversive treatment piglets spent most time at rest or exploring (P>0.05). However, in rational treatment the piglets remained resting most of the time (P 0.05). The interactions between pigs in the first phase of life are
O artigo não apresenta resumo em português.
Resumo
Cattle, when in heat stress, deflect energy to increase dissipation to environment, compromising productivity. Thus, in dairy production system it is important to maintain thermal comfort to ensure homeothermy and full performance. One of the physiological measures to evaluate thermal comfort of domestic animals is hair coat surface temperature. Knowing this temperature allows the understanding whether animal performs thermal exchanges by convection through the activation of heat dissipation latent mechanisms. This study aimed to evaluate body surface temperature in crossbred dairy cows on Triângulo Mineiro climatic conditions. This was carried out at Estação Experimental Glória of Universidade Federal de Uberlândia using 53 lactating crossbred cows. Cows were housed in shaded pen for artificial insemination and after it was performed body surface temperature mensurements. Temperature was measured from body surface at four different regions: forehead, withers, groin and hock using an Instruterm infrared thermometer model TI-890. The statistical model used the region to test the effect of surface temperature comparing means by Tukeys test, with a significance level of 5%. Means and standard deviations of ambient temperature, maximum temperature, minimum temperature and relative humidity were respectively 23.96 ± 2.57C; 29.43 ± 2.50C; 17.54 ± 2.38C; and 67.18 ± 15.39%. Temper
O artigo não apresenta resumo em português.
Resumo
In tropical and subtropical regions animals suffer pronounced heat stress effect on reproductive function, being one of the most noticeable effects the reduction of conception rate. When evaluating animals heat stress, rectal temperature measurement is important tool because indicates heat release mechanisms became insufficient to maintain homeothermy. This study aimed to evaluate body temperature at fixed time artificial insemination of crossbred dairy cows and their conception at 30 days pregnacy. Experiment was performed from April 26, 2010 to January 28, 2012 at Estação Experimental Glória of Universidade Federal de Uberlândia, at Triângulo Mineiro, Brazil. One hundred-twelve crossbred dairy cows and heifers were used. At the moment of insemination, animals were housed in shaded pen and body temperature was collect using clinical thermometer introduced in rectal mucosa. Environmental variables collect were air temperature, maximum temperature, minimum temperature and relative humidity. Data were analyzed in two different periods: from April to September (mild weather-MW) and from October to March (hot weather-HW). The statistical model included the effect of category, period, pregnancy diagnosis and their interactions, comparing means by Tukeys test, with a significance level of 5%. Means and standard deviations of air temperature, maximum temperature, minimum temperature
ptmo em português.
Resumo
The work aims to analize the behavior response and the ability to cope stressors when the piglets are exposed to aggressive treatment during the lactation phase. The behavior of 40 piglets was observed from birth to weaning (28 days). In the first fifteen days the observations were done every three days, with an interval of another three days. After this period, the observations were done once a week. Over a period of three hours, every five minutes it was registered the animal behavior. The group was divided into two treatments: rational group, where 18 piglets had minimal interaction with people and it was permitted the routine practice without sudden movements and loud sounds; and the aversive treatment, where 22 piglets received the daily routine of the farm, however, on every half hour during observations the observer performed a direct threat to the sow going into the cage with a flag and abruptly approach the animal, shouting or clapping. To avoid visual contact with the observer, he was located behind the maternity cage. Analysis of variance with fixed effects of time and time and means were compared by Tukey test or T at 5% of significance. In aversive treatment piglets spent most time at rest or exploring (P>0.05). However, in rational treatment the piglets remained resting most of the time (P 0.05). The interactions between pigs in the first phase of life are
O artigo não apresenta resumo em português.
Resumo
It is evident the necessity of a better understanding regarding the influence of warmth on the performance of horses in training, establishing that an efficient thermoregulation is essential to provide the physiological demands resulting from effort required and the climatic variables which the animal is exposed. This study aimed to evaluate thermoregulation in horses subjected to 30 minutes of exercise during three periods of the day with different air temperatures and to compare two techniques for measuring the sweating rate (SR) and trans epidermal water loss (TEWL). Three castrated crossbred horses were submitted to a series of half an hour of exercise at different moments (07:00, 13:00, 16:00 hours), carried out as follows: 3 minutes walking, 3 minutes of canter, 10 minutes of trot, 10 minutes of canter, 2 minutes of trot and 2 minutes of canter. Relative humidity, black globe and air temperature were 50%, 34Cº and 20.8ºC; 62%, 35ºC and 28.8Cº; 48%, 34.5Cº and 27.4Cº; respectively for the three periods. Rectal temperature (RT), respiratory rate (RR), body surface temperature (BST), SR through the methodology of Schleger and Turner (1965) and TEWL measured by VapoMeter (Delfin, Finland) were taken before and after exercise. Model for analysis of variance included fixed effects of time and moments, and the means were compared by Tukey test or T at 5% of significance. Signifi
O artigo não apresenta resumo em português.
Resumo
The stress in animals is linked with possible unusual changes that reduce the individual welfare. These changes generally related to the environment or to animal physiology cause imbalance in the biological reactions as a defense by releasing certain substances, including cortisol. There are few studies which indicate that there is heritable consequences promoted by cortisol generated by stress during pregnancy on the first hours of life of the lamb and the gestational phase (days of gestation) in which stress was promoted also interferes with it. Thus, the aim of this study was to evaluate during the delivery time the cortisol levels of lambs and sheep subjected to stress in different weeks of pregnancy and the effect on the birth weight of the lambs. The study was approved by Ethics Committee of FZEA/USP (13.1.2109.74.8). Forty crossbred Santa Ines ewes, multiparous, with an average age of 5 years and 60 kg of body weight (BW), grazing on Coast-cross were used (Cynodon dactylon (L.) Pers.) on rotated system, with free access to shade, water and mineral supplementation. All experimental ewes were artificially inseminated with semen from White Dorper breed. During gestation, the ewes were divided into three groups on a completely randomized design: CG - control group of 15 animals that were not subjected to stress; GI - intermediate group of 12 animals that suffered stress at 7
O artigo não apresenta resumo em português.
Resumo
To analyze stress during the intermediate stage of gestation, 43 multiparous, crossbred Santa Inês, pregnant ewes, with a average age of 5 and average body weight (BW) of 60kg, were challenged with a intravenous administration of 0.8µg.kg-1 of LPS (lipopolysaccharide E. coli - outer membrane cell of gram-negative bacteria), diluted in physiological saline solution - simulating an immune stressor. The females were placed in individual cages at feedlot, with adaptation period of 5 days before the begin of sampling, with free access to good water quality, shade and food in the trough (corn silage and mineral supplementation). The ewes were divided into three groups, with a completely randomized design (CRD): CG - control group, with 15 animals that were not subjected to stress; IG - intermediate group stage, with 14 animals undergoing stress at 70 days of gestation; FG final group, made up of 14 animals undergoing stress at 120 days of gestation. The variables used to investigate stress were measured during the intermediate stages of pregnancy in a 24 hour sampling, with this was possible to observe the change in rectal temperature (RT) and blood levels of cortisol by its circadian rhythm. Shortly after the baseline sampling, the treatment corresponding to the intermediate stage of gestation was submitted to stress, with the sampling interval of one hour each, from the first to
O artigo não apresenta resumo em português.