Altrenogest during early pregnancy modulates uterine glandular epithelium and endometrial growth factor expression at the time implantation in pigs

This study evaluated the effects of supplying altrenogest from day 6-12 of pregnancy on the endometrial glandular epithelium, corpora lutea (CL) morphology, and endometrial and CL gene expression. A total of 12 crossbred females (Landrace × Large White) were used. The females were assigned to 4 treatments according to a random design with a 2 × 2 factorial arrangement, with two categories (sow or gilt) and two treatments (non-treated and treated with altrenogest). On day 6 of pregnancy, animals were allocated to one of the following groups: non-treated (NT, n = 6; 3 sows and 3 gilts), and (T, n = 6; 3 sows and 3 gilts) treated daily with 20 mg of altrenogest, from day 6-12 of pregnancy. All animals were euthanized on day 13 of pregnancy. All CLs were individually weighed, and their volume were determined. The endometrial glandular density (GD), mean glandular area (MGA), and vascular density (VD) were determined by histomorphometric and immunohistochemical analyses. Endometrium samples were collected and analyzed by qRT-PCR to evaluate the abundance of transcripts for VEGF and IGF-I. Females in the T group had higher MGA (P < 0.05) compared to the NT group. There was no effect of treatment on GD or VD for both experimental groups. Sows in the T group had augmented expression of IGF-I (P < 0.05). Progestagen had no detrimental effect on CL morphology. In conclusion, altrenogest improves the uterine environment during the peri-implantation period in pigs without compromising corpora lutea development.(AU)

Influência da nutrição na reprodução das matrizes suínas / Nutrition influence on female swine reproduction

To attend the growing demand of the swine industry for a greater number of piglets weaned per sow per year, genetic improvement programs have created a hyper prolific sow; this genetic selection has led to an increase in milk production, in the number of piglets born, reduction in voluntary feed intake, a greater lean muscle tissue deposition as well as in a decreased body fat reserves. However, such reduction in feed consumption can be very detrimental, especially for primiparous sows since, during lactation, there is a tremendous mobilization of body reserves in order to compensate a reduced feed intake and to attend the nutritional demand for milk yielding. In this sense, high-prolific sows have higher nutritional demand and therefore they require a differentiated nutritional program to avoid reproductive and productive losses. On this path, several studies have been developed and new will be necessary to adjust the nutrient demand at different stages to the production profile of sows aiming to extend the reproductive life span of the female swine.

Na busca de se aumentar o número de leitões desmamados por porca ao ano, o melhoramento genético tornou as matrizes suínas hiperporlíficas, levando ao aumento na produção de leite, número de leitões nascidos, a redução no consumo voluntário, a maior deposição de tecido muscular e menores reservas de tecido adiposo. Esse reduzido consumo de ração é preocupante principalmente em primíparas, pois durante a lactação, mobilizam suas reservas corporais para compensar a ingestão reduzida e atender a demanda nutricional para a produção de leite. As matrizes hiperprolíficas apresentam exigências nutricionais mais elevadas e por isso necessitam de um programa nutricional diferenciado, de modo a evitar severos comprometimentos reprodutivos e produtivos. Diversos estudos vêm sendo desenvolvidos e novos ainda serão necessários para adequar a demanda nutricional nas diferentes fases ao perfil produtivo das fêmeas, a fim de prolongar a vida útil reprodutiva das matrizes suínas.

Influência da nutrição na reprodução das matrizes suínas / Nutrition influence on female swine reproduction

To attend the growing demand of the swine industry for a greater number of piglets weaned per sow per year, genetic improvement programs have created a hyper prolific sow; this genetic selection has led to an increase in milk production, in the number of piglets born, reduction in voluntary feed intake, a greater lean muscle tissue deposition as well as in a decreased body fat reserves. However, such reduction in feed consumption can be very detrimental, especially for primiparous sows since, during lactation, there is a tremendous mobilization of body reserves in order to compensate a reduced feed intake and to attend the nutritional demand for milk yielding. In this sense, high-prolific sows have higher nutritional demand and therefore they require a differentiated nutritional program to avoid reproductive and productive losses. On this path, several studies have been developed and new will be necessary to adjust the nutrient demand at different stages to the production profile of sows aiming to extend the reproductive life span of the female swine.(AU)

Na busca de se aumentar o número de leitões desmamados por porca ao ano, o melhoramento genético tornou as matrizes suínas hiperporlíficas, levando ao aumento na produção de leite, número de leitões nascidos, a redução no consumo voluntário, a maior deposição de tecido muscular e menores reservas de tecido adiposo. Esse reduzido consumo de ração é preocupante principalmente em primíparas, pois durante a lactação, mobilizam suas reservas corporais para compensar a ingestão reduzida e atender a demanda nutricional para a produção de leite. As matrizes hiperprolíficas apresentam exigências nutricionais mais elevadas e por isso necessitam de um programa nutricional diferenciado, de modo a evitar severos comprometimentos reprodutivos e produtivos. Diversos estudos vêm sendo desenvolvidos e novos ainda serão necessários para adequar a demanda nutricional nas diferentes fases ao perfil produtivo das fêmeas, a fim de prolongar a vida útil reprodutiva das matrizes suínas.(AU)

Ausência de efeito do análogo (hCG) do hormônio luteinizante na angiogênese luteal em ratas (Rattus novergicus) / Faillure in the effect of the analogue (hCG) of luteinizing hormone on the luteal angiogenesis in rats (Rattus novergicus)

A compreensão dos mecanismos de controle da atividade ovariana é necessária para o sucesso das biotecnologias da reprodução. Embora existam inúmeros trabalhos a respeito da aplicação do hormônio luteinizante (LH) na função ovariana, pouco se sabe sobre a sua influência na morfologia e formação da vasculatura do corpo lúteo (CL). Diante disto, o presente projeto teve como objetivo a quantificação da densidade vascular dos CLs de animais tratados com Gonadotrofina Corionica Humana (hCG) após a ovulação. Para tanto, foram utilizados ratas wistar, cujos CLs foram divididos em dois grupos: (A) tratado com hCG na manhã seguinte a cópula e (B) controle (solução fisiológica a 0,9 % de NaCl). Foram confeccionadas lâminas dos ovários dos animais para a quantificação da densidade vascular. Os resultados obtidos não revelaram diferenças significantes entre a densidade vascular dos grupos tratado e controle.(AU)

The knowledge of the mechanisms that affect the control of the ovarian activity is essential for the success of reproduction biotechnologies. Although a number of studies have been carried out in which the luteinizing hormone (LH) was used to control the ovarian activity, little is known about its influence in the morphology and vascular formation of the corpus luteum, aiming to increase the local blood flow. Thus, the objective of the present experiment was the quantification of the vascular density of corpora lutea (Cls) in animals treated with human chorionic gonadotropin (hCG) just after ovulation. Therefore, eighteen wistar rats were used in this experiment . Eight rats in the treated group and ten rats in the control group. Corpora lutea were divided into two groups: group (A) treated with hCG in the following morning after copulation, and group (B) control animals which received an injection of 0.9% sodium chloride solution. Ovaries from each group were used for preparation of histological sections for vascular density qualification. No statistical significance was found between the two groups tested.(AU)