ABSTRACT
Objetivou-se avaliar a produção e qualidade do leite em vacas meio sangue (Holandesa x Zebu) em função da presença do bezerro durante a ordenha e/ou da administração de ocitocina exógena. Foram utilizadas oito vacas meio sangue (holandesa x zebu), multíparas, distribuídas em dois quadrados latinos (4x4) em esquema fatorial (2x2), com e sem a presença do bezerro durante a ordenha, e com a utilização, ou não, de ocitocina exógena. Foi realizada a contagem de células somáticas (CCS) e contagem bacteriana total (CBT/mL) e ainda determinados os teores de lactose, gorduras totais, proteína, sólidos totais e extrato seco desengordurado das amostras. Os animais que foram ordenhados com os bezerros lactentes e os com a utilização de ocitocina exógena via intravenosa apresentaram maior produção diária de leite em kg. Não houve interação entre os efeitos, podendo se utilizar qualquer um dos métodos para a estimulação da contração alveolar. A utilização de ocitocina ou a presença do bezerro não causa interferência na qualidade ou na composição do leite de vacas mestiças. A ordenha na presença do bezerro e a utilização de ocitocina promovem aumento da produção láctea.
Milk yield and milk quality were evaluated in ½ holstein/zebu cows, with or without the calf presence or oxytocin injection. It was used eight ½ holstein/zebu cows, multiparous, distributed in two Latin squares (4x4) in factorial scheme (2x2), with or without calf presence, and whith or without oxytocin injection. The milk was analyzed for somatic cells count (SCC), total bacterial count (TBC/mL), lactose, total fat, protein, total solids, and no fat dry matter concentration. The animals milked with calves and with ocytocin injection showed a higher milk production. There was no interaction between the effects, and any one of the methods may used for stimulation of aveolar contraction. The calf presence and oxytocin injection during milking results in higher milk production, but no changes in milk quality and composition of ½ holstein/zebu cows.
Subject(s)
Animals , Food Quality , Milk , Oxytocin/chemistry , Hormones/analysisABSTRACT
Exposure to maternal separation in early life is associated with alteration in the neuroendocrine and neurotransmitter system which may be associated with risk of psychiatric disorders development at adulthood. The aim of this study was to [i] assess levels of monoamines [dopamine, nor-epinephrine, epinephrine and serotonin] in rat pup's brain following repeated maternal separation [RMS] and maternal deprivation [MD]. [ii] Assess brain corticosterone and oxytocin level following both RMS and MD. This study was carried out on 50 male rat pups divided into 3 experimental groups; Group I: 20 rats subjected to 3 h of repeated maternal separation for 14 days; Group II: 20 rats subjected to 24 h of maternal deprivation; Group III: 10 rats served as control group. At the end of the experimental period, all rats were sacrificed and their brains were rapidly removed and dissected for estimation of monoamines, corticosterone and oxytocin. Brain corticosterone level showed marked increase after both separation procedures, however, MD was associated with marked increase. RMS was associated with higher level of epinephrine, norepinephrine, dopamine and serotonin. Dopamine and serotonin levels however, were reduced after MD. Oxytocin level showed marked reduction after MD and RMS. The current work provided some neurobiological evidence supporting the determinant role of mother-infant relationship in the development of psychopathology. Maternal separation leads to profound alterations in the central neurotransmitter system and therefore is associated with increased risk of psychiatric disorders as depression and anxiety. Moreover, maternal separation has impact on the corticosterone and oxytocin release in the brain. Different separation procedures however, can influence the consequences of MS