Effects of 4-Nonylphenol on reproduction of exposed females during puberty

4-Nonylphenol (NP) is considered an endocrine disruptor due to its capacity to interact with endocrine system, mimicking estrogen activity. It is aubiquitous pollutant since it has been found in many human tissue samples and its precursor identified in sewage, sediments, rivers and drinking water. Thus, this work aimed to evaluate reproductive parameters in female Balb/C mice treated with 50 mg/kg body weight of NP for 21 days, a period in which they reach sexual maturity. Body weight during treatment, day of vaginal opening, organs weight, fertility rate and proportion of different follicle types were some of these parameters. Additionally, for analysis of some effect in littermates, a group of animals underwent two attempts at pregnancy after treatment. NP had no effect on body weight during treatment, nor did it alter the day of vaginal opening and fertility rate of females. The proportion of preantral, antral and degenerated ovarian follicles was not modified by treatment with NP, and no morphological or pathological alterations were observed. The number of pups did not differ between treatments in any attempt at pregnancy. Also the weight of pups on birth and female rate in littermates was similar among experimental groups after both trials of pregnancy. It is suggested that the NP available or accumulated during the period of sexual maturation (21 days) did not reach threshold levels capable of producing significant alterations in the reproductive parameters analyzed.

Effects of 4-Nonylphenol on reproduction of exposed females during puberty

4-Nonylphenol (NP) is considered an endocrine disruptor due to its capacity to interact with endocrine system, mimicking estrogen activity. It is aubiquitous pollutant since it has been found in many human tissue samples and its precursor identified in sewage, sediments, rivers and drinking water. Thus, this work aimed to evaluate reproductive parameters in female Balb/C mice treated with 50 mg/kg body weight of NP for 21 days, a period in which they reach sexual maturity. Body weight during treatment, day of vaginal opening, organs weight, fertility rate and proportion of different follicle types were some of these parameters. Additionally, for analysis of some effect in littermates, a group of animals underwent two attempts at pregnancy after treatment. NP had no effect on body weight during treatment, nor did it alter the day of vaginal opening and fertility rate of females. The proportion of preantral, antral and degenerated ovarian follicles was not modified by treatment with NP, and no morphological or pathological alterations were observed. The number of pups did not differ between treatments in any attempt at pregnancy. Also the weight of pups on birth and female rate in littermates was similar among experimental groups after both trials of pregnancy. It is suggested that the NP available or accumulated during the period of sexual maturation (21 days) did not reach threshold levels capable of producing significant alterations in the reproductive parameters analyzed.(AU)

Resposta de vacas leiteiras à substituição total de milho por polpa cítrica e à suplementação com microminerais orgânicos I: consumo e digestão / Response of lactating cows to the total replacement of corn by citrus pulp and to the supplementation of organic trace minerals I: intake and digestion

Avaliou-se a resposta de vacas leiteiras à substituição total de milho maduro finamente moído por polpa cítrica peletizada. O teor dietético do milho foi 10 por cento e o de polpa 24 por cento nos tratamentos com milho, e o de polpa foi 33 por cento nas dietas exclusivas com polpa. Simultaneamente, foi avaliada a substituição total de fontes inorgânicas de Cu, Mn, Se, Zn e Cr por fontes orgânicas. Quatro dietas baseadas em silagem de milho foram geradas por arranjo fatorial dos dois fatores. Dezesseis vacas receberam os tratamentos em quadrado latino 4x4. O efeito da substituição de fontes inorgânicas por fontes orgânicas de microminerais não foi conclusivo. O consumo diário de matéria seca foi 19,4kg na polpa e 20,5kg na dieta com milho (P=0,03). O consumo de matéria orgânica digestível foi maior nas dietas com milho (P<0,01). Houve tendência de queda na taxa fracional de degradação ruminal in situ da MS da silagem de milho (P=0,11) e de aumento no tamanho da fração indigestível (P=0,15) nas dietas com milho, sugerindo que a degradação de forragens não determinou o menor consumo nas dietas com polpa. A substituição total de milho por polpa cítrica pode reduzir o consumo e a digestibilidade.(AU)

The response of lactating cows to the total replacement of finely ground mature corn by pelleted citrus pulp was evaluated. Treatments with corn contained 10 percent corn and 24 percent citrus pulp while citrus diets contained 33 percent citrus pulp. The complete replacement of inorganic sources of Cu, Mn, Se, Zn, and Cr by organic sources was simultaneously evaluated. Four corn silage based diets were generated by a factorial arrangement of the two factors. Sixteen cows received the treatments in 4x4 latin squares. The effect of substituting inorganic by organic mineral sources was not conclusive. Daily dry matter intake was 19.4kg for citrus diets and 20.5kg with corn (P=0.03). The digestible organic matter intake was increased by corn supplementation (P<0.01). There was a trend for a decreased fractional rate of in situ ruminal degradation of corn silage dry matter (P=0.11) and for increased size of the indigestible fraction (P=0.15) in diets with corn, suggesting that degradation of forages did not determine the lower intake for citrus diets. The total substitution of corn by citrus pulp may decrease intake and digestibility.(AU)