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
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 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.