Glycerin supplementation strategies for three or seven days affects oxidative stress, follicle dynamics and ovulatory response in Morada Nova sheep

The Ziwuling black goat is an indigenously in China, their offspring are frequently affected by congenital cryptorchidism. The extracellular matrix (ECM) contains cytokines and growth factors that regulate the development of the testis, and component changes often result in pathological changes. Cryptorchidism is closely related to structural changes in ECM. In this study, the histochemical staining, immunohistochemical, immunofluorescence and Western blot combined with semi-quantitative analysis was used to describe the distribution of the important ECM components Collagen type IV (Col IV), laminin (LN)and heparan sulfate proteoglycans (HSPG) in the normal and cryptorchid testes of Ziwuling black goats. Results showed that: The histochemical staining showed that the dysplasia of seminiferous tubules and decreased number of Sertoli cells in cryptorchidism, as well as sparse collagen fiber. Meanwhile, the distribution of reticular fibers is relatively rich. Furthermore, the PAS and AB staining in the interstitial vessels and lamina propria of seminiferous tubules is weak. The immunohistochemical and immunofluorescence revealed that Col IV, LN was strongly expressed in Leydig, Sertoli cells of normal testes and moderately positive in the spermatogonia and spermatids, but HSPG was not expressed in the spermatogonia. However, cryptorchidism, the expression of Col IV, LN and HPSG in Leydig, Sertoli cells significantly decreased, as well as the expression of Col IV and LN in capillary endothelial cells, but HSPG was moderately expressed in spermatogonia. Based on these data, the underdevelopment of spermatogenic epithelium, decreased synthesis function of collagen fibers and Leydig cells develop usually in the cryptorchidism were shown to be closely related to the abnormal metabolism of Col IV and LN. The positive expressed of HSPG in the spermatogonia of cryptorchid testes is related to the compensatory development of spermatogonia.(AU)

Intravaginal progesterone device (1. 9g) and estradiol benzoate for follicular control in the mare during spring and summer / [Implante intravaginal de progesterona (1, 9g) e benzoato de estradiol no controle folicular de éguas durante a primavera e o verão]

The objective of this study was to evaluate follicular growth and ovulatory rates in mares treated with an intravaginal progesterone device (P4) during the 10-day period, associated with the use of estradiol benzoate (EB). The results were compared during the transition period (ET) in the spring and the breeding season in the summer (ER). The variables were submitted to ANOVA (Tukey's test), considering P<0.05. No ovulation occurred during the permanence of the P4 implant in both experimental periods. The ovulatory rate in the ER was 100% (n = 8) and in the ET 62.5% (n = 5; P = 0.0547). Significant differences were observed (<0.001), in both periods, comparing follicular growth rates during the permanence of P4 device (ER: 1.33 ± 0.89mm/d; ET: 1.00 ± 0.81mm/d) to the period without P4 (ER: 3.63 ± 1.33 mm/d; ET: 3.31 ± 1.66 mm/d). The present study demonstrated applicability and efficiency of a hormonal protocol using P4 intravaginal device and EB for follicular control in mares, both during ET and ER.

O objetivo deste trabalho foi avaliar a taxa de crescimento folicular e a taxa ovulatória em éguas tratadas com dispositivo intravaginal de progesterona (P4) durante o período de 10 dias, associado à utilização de benzoato de estradiol (BE). Os resultados foram comparados durante o período de transição (ET) da primavera com a época de reprodução no verão (ER). As variáveis foram submetidas à ANOVA (teste de Tukey), considerando-se P<0,05. Nenhuma ovulação ocorreu durante a permanência do dispositivo de P4 em ambos os períodos experimentais. A taxa ovulatória na ER foi de 100% (n = 8) e na ET, de 62,5% (n=5; P=0,0547). Diferença significativas (<0,001) foram observadas, em ambos os períodos experimentais, comparando as taxas de crescimento folicular durante a permanência da P4 (ER: 1,33 ± 0,89mm/d; ET: 1,00 ± 0,81mm/d) com o período sem P4 (ER: 3,63 ± 1,33mm/d; ET: 3,31 ± 1,66mm/d). O presente estudo demonstrou aplicabilidade e eficiência do protocolo hormonal utilizando dispositivo intravaginal de P4 e BE para controle folicular de éguas, tanto na ET quanto na ER.

INDUÇÃO DE DUPLA OVULAÇÃO EM ÉGUAS MANGALARGA MARCHADOR

Uma das estratégias para aumentar a eficiência dos programas de transferência de embriões em equinos é a indução de múltiplas ovulações. Neste contexto o objetivo do presente estudo foi avaliar a eficiência em de agonistas do GnRH para indução de duplas ovulações, bem como na taxa de ovulação e recuperação embrionária nos grupos estudados. Foram avaliados 41 ciclos estrais de éguas Mangalarga Marchador. Todos os animais foram induzidos ao estro no 8o dia do ciclo estral (D8) com 5 mg de dinoprost trometamina e quando foram observados ao menos dois folículos de tamanho entre 17 e 19 mm, os ciclos foram divididos em três grupos de tratamento: Grupo I (n=13 ciclos) - 100 µg de acetato de deslorelina, a cada 12 horas; Grupo II (n=14 ciclos) - 125 µg de acetato de histrelina, a cada 12 horas e Grupo III (n= 14 ciclos) considerado grupo controle, no qual foi administrado 1,0 ml de solução salina a cada 12 horas. A duração do tratamento com análogos de GnRH não excedeu sete dias, sendo interrompido quando a maioria dos folículos atingissem diâmetro 35 mm e edema uterino ou quando os mesmos cessassem o crescimento. A indução da ovulação foi realizada utilizando 1000 UI de hCG intravenoso quando o folículo atingisse um diâmetro médio entre eles de 35 mm e edema uterino. A partir da indução da ovulação, 24 horas após as éguas foram inseminadas com sêmen a fresco de um garanhão de fertilidade comprovada. A colheita de embriões foi realizada no oitavo dia após a detecção da ovulação. O número médio de ovulações por ciclo de 1,15 (GI), 0,86 (GII) e 1,14 (GIII). Quanto o número de embriões recuperados por ovulação, os grupos I, II e III apresentaram, 0,46, 0,36 e 0,71. Já o número de embriões recuperados por ciclo foi de 0,67 (GI), 0,50 (GII) e 0,71 (GIII). Não foi observada diferença estatística entre os grupos de tratamento (P > 0,05). Conclui-se que os protocolos propostos não foram capazes de aumentar as taxas de duplas ovulações nos grupos avaliados assim como a taxa de recuperação embrionária

One of the strategies to increase the efficiency of embryo transfer programs in horses is the induction of multiple ovulations. In this context, the objective of the present study was to evaluate the efficiency of GnRH agonists for inducing double ovulations, as well as the rate of ovulation and embryonic recovery in the studied groups. 41 estal cycles of Mangalarga Marchador mares were evaluated. All animals were induced to estrus on the 8th day of the estrous cycle (D8) with 5 mg of dinoprost tromethamine and when at least two follicles between 17 and 19 mm in size were observed, the cycles were divided into three treatment groups: Group I (n = 13 cycles) - 100 µg of deslorelin acetate, every 12 hours; Group II (n = 14 cycles) - 125 µg of histrelin acetate, every 12 hours and Group III (n = 14 cycles) considered a control group, in which 1.0 ml of saline solution was administered every 12 hours. The duration of treatment with GnRH analogs did not exceed seven days, being interrupted when most follicles reached a diameter 35 mm and uterine edema or when they stopped growing. Ovulation induction was performed using 1000 IU intravenous hCG when the follicle reached an average diameter between them of 35 mm and uterine edema. After ovulation induction, 24 hours after the mares were inseminated with fresh semen from a proven fertility stallion. Embryo collection was performed on the eighth day after ovulation was detected. The average number of ovulations per cycle is 1.15 (GI), 0.86 (GII) and 1.14 (GIII). Regarding the number of embryos recovered by ovulation, groups I, II and III showed 0.46, 0.36 and 0.71. The number of embryos recovered per cycle was 0.67 (GI), 0.50 (GII) and 0.71 (GIII). There was no statistical difference between the treatment groups (P> 0.05). It is concluded that the proposed protocols were not able to increase the rates of double ovulations in the evaluated groups as well as the rate of embryo recovery

Energy supplementation in Santa Inês sheep subjected to estrus induction treatment / Suplementação calórica em ovelhas da raça Santa Inês submetidas à indução do estro sincronizado

The aim of this study was to evaluate the effect of a 20% increase in dietary energy during short-term estrus induction treatment on the reproductive parameters of Santa Inês ewes. Females (n=43) were allocated into two experimental groups according to the amount of energy inclusion in the diet: maintenance diet or maintenance diet plus 20% energy. Ultrasound examinations were performed in order to detect ovulation. To assess sexual behavior, ewes were teased and further mated. Blood samples were collected for the determination of glucose and insulin concentrations. There was no difference (P>0.05) between groups in the following categories: ovulation rate (80.00% vs. 60.00%), largest follicle diameter (6.00 ± 0.20 vs. 5.90 ± 0.60), interval from device removal to ovulation (52.80 ± 14.87 vs. 59.01 ± 8.34 hours), animals in estrus (75.00% vs. 65.21%), interval from device removal to estrus (30.00 ± 15.49 vs. 30.00 ± 13.35 hours) and conception rate (50.00% vs. 21.73%). There were differences (P<0.05) in the concentrations of insulin and glucose. It can be concluded that the 20% increase in energy in the diet during short-term estrus induction treatment did not affect the reproductive parameters studied.(AU)

O objetivo deste estudo foi avaliar o efeito do aumento em 20% da energia da dieta durante um protocolo curto de sincronização do estro sobre os parâmetros reprodutivos e metabólicos em ovelhas da raça Santa Inês. As ovelhas (n=43) foram distribuídas em dois grupos experimentais de acordo com a quantidade de energia incluída na dieta, onde foram utilizadas uma dieta de manutenção e uma dieta de manutenção acrescida em 20% de energia. Exames ultrassonográficos foram realizados para detectar a ovulação, bem como o diâmetro dos folículos. Para avaliação do comportamento sexual as ovelhas foram rufiadas. Foram coletadas amostras de sangue para determinação das concentrações plasmáticas de glicose e insulina. Não houve diferença (P>0,05) entre os grupos para: taxa de animais ovulando (80% vs 60%), diâmetro do maior folículo (6,00 ± 0,20 vs 5,90 ± 0,60), intervalo da retirada do implante à ovulação (52,80 ± 14,87 vs 59,01 ± 8,34 horas), animais em estro (75,00% vs 65,21%), intervalo da retirada do implante ao estro (30,00 ± 15,49 vs 30,00 ± 13,35 horas) e taxa de concepção (50,00% vs 21,73%). Houve diferença (P<0,05) nas concentrações de insulina e glicose. Pode-se concluir que o aumento em 20% da energia da dieta durante um protocolo curto de sincronização do estro não alterou os parâmetros reprodutivos.(AU)

Effect of oral drenching of glycerin as a source of pre-mating energetic supplementation on reproductive response in goats

The availability of glycerol has increased because of the biofuels industry, and glycerol can have a significant effect on reproductive efficiency when used as an alternative energy source in animal feeds. The aim of this study was to investigate the effects of pre-mating oral drenching of glycerin on ovarian and fertility responses in goats. Sixty Anglonubian mixed-breed goats were submitted to estrus synchronization by CIDR-prostaglandin PGF2α treatment and mated. At CIDR removal, onset of estrus, and 24 h after estrus behavior, the animals received 150 ml of saline solution (control group, n = 20), 150 ml of glycerol (150 ml group, n = 20), or 300 ml of glycerol (300 ml group, n = 20). The administration of glycerin increased plasma glucose in the 300 ml group (P < 0.05) and the insulin concentration at 12 h after glycerin drenching in both treated groups. Goats from the 300 ml group showed a lower ovulation rate when compared to the control group (1.15 ± 0.08 vs. 0.89 ± 0.14; P < 0.05) but exhibited larger follicles at 48, 24, and 12 h prior to ovulation (P < 0.05). Administration of 300 ml of glycerol was also associated with a significant reduction in the pregnancy rate (80.00% vs. 38.89%; P < 0.05) and in pregnant animals it was associated with lower growth of embryonic vesicles (1.78 ± 0.07 mm/day vs. 1.31 ± 0.07 mm/day; P < 0.05) compared to the control treatment. Gestational losses in the 300 ml group occurred between mating and the 45th day of pregnancy. No differences were found for the reproductive parameters analyzed in the study between the 150 ml and control groups. In conclusion, the supplementation with glycerol before the mating did not appear to be a viable alternative to increase reproductive efficiency of adult does.(AU)

Effect of oral drenching of glycerin as a source of pre-mating energetic supplementation on reproductive response in goats

The availability of glycerol has increased because of the biofuels industry, and glycerol can have a significant effect on reproductive efficiency when used as an alternative energy source in animal feeds. The aim of this study was to investigate the effects of pre-mating oral drenching of glycerin on ovarian and fertility responses in goats. Sixty Anglonubian mixed-breed goats were submitted to estrus synchronization by CIDR-prostaglandin PGF2α treatment and mated. At CIDR removal, onset of estrus, and 24 h after estrus behavior, the animals received 150 ml of saline solution (control group, n = 20), 150 ml of glycerol (150 ml group, n = 20), or 300 ml of glycerol (300 ml group, n = 20). The administration of glycerin increased plasma glucose in the 300 ml group (P < 0.05) and the insulin concentration at 12 h after glycerin drenching in both treated groups. Goats from the 300 ml group showed a lower ovulation rate when compared to the control group (1.15 ± 0.08 vs. 0.89 ± 0.14; P < 0.05) but exhibited larger follicles at 48, 24, and 12 h prior to ovulation (P < 0.05). Administration of 300 ml of glycerol was also associated with a significant reduction in the pregnancy rate (80.00% vs. 38.89%; P < 0.05) and in pregnant animals it was associated with lower growth of embryonic vesicles (1.78 ± 0.07 mm/day vs. 1.31 ± 0.07 mm/day; P < 0.05) compared to the control treatment. Gestational losses in the 300 ml group occurred between mating and the 45th day of pregnancy. No differences were found for the reproductive parameters analyzed in the study between the 150 ml and control groups. In conclusion, the supplementation with glycerol before the mating did not appear to be a viable alternative to increase reproductive efficiency of adult does.

UTILIZAÇÃO DE GLICERINA COMO SUPLEMENTO ENERGÉTICO EM OVELHAS MORADA NOVA: EFEITO DA FORMA E TEMPO DE ADMINISTRAÇÃO SOBRE A DINÂMICA FOLICULAR, ESTRESSE OXIDATIVO E RESPOSTA OVARIANA

O glicerol, presente na glicerina adotada na alimentação animal, é considerado um aditivo glicogênico de grande valia que promove alterações metabólicas que elevam as concentrações plasmáticas de glicose, favorecendo as reservas energéticas dos animais. Assim, o objetivo deste trabalho foi avaliar o efeito das estratégias de fornecimento de glicerina em diferentes protocolos de suplementação ultra-curta sobre a dinâmica folicular e a taxa ovulatória de ovelhas da raça Morada Nova. Dezoito ovelhas Morada Nova foram sincronizadas por meio da administração de um análogo da prostaglandina (PGF2) seguindo protocolo intercalado de 7 dias. A dieta foi fornecida método de ração mista total (TMR) e as ovelhas dos grupos-tratamento foram suplementadas com 150 mL de glicerol na forma de solução de glicerina, diariamente por três (Drench3d e TMR3d) ou sete (Drench7d e TMR7d) dias. O monitoramento da dinâmica folicular foi realizado por ultrassonografia e os níveis de glicose plasmática e glutationa peroxidase foram medidos na terceira administração de PGF2. A taxa ovulatória de todos os grupos foi avaliada seis dias após a dose final de prostaglandina por laparoscopia. Observou-se maiores níveis de glicose nos grupos tratamento em relação à dieta controle. Nos grupos TMR3d, Drench7d e TMR7d houve maior proporção (P < 0,001) de folículos grandes ( 3 < 5 mm); com observação de folículos com tamanho superior a 5mm. Nos mesmos grupos pode-se registrar na terceira dose PGF2, um número maior (P < 0,001) de folículos em crescimento (> 3 mm), e um maior tamanho do maior folículo (P < 0,001). Nos grupos onde a glicerina foi adicionada durante 7 dias (Drench7d e TMR7d) a taxa ovulatória apresentou um aumento de 30%, em relação ao grupo controle, sendo observado também uma redução de 38% nos níveis de glutationa peroxidase. Com base em nossos achados, o uso de glicerina na suplementação energética de curta duração para ovelhas Morada Nova foi bem sucedido quando fornecida por sete dias.

Glycerol, present in glycerin adopted in animal feed, is considered a glycogenic additive of great value that promotes metabolic changes that increase plasma glucose concentrations, favoring the energy reserves of animals. Thus, the objective of this work was to evaluate the effect of glycerin supply strategies in different ultra-short supplementation protocols on follicular dynamics and ovulation rate of Morada Nova sheep. Eighteen Morada Nova sheep were synchronized through the administration of a prostaglandin analogue (PGF2) following a 7-day interleaved protocol. The diet was provided with total mixed feeding method (TMR) and the sheep of the treatment groups were supplemented with 150 mL of glycerol in the form of glycerine solution, daily for three (Drench3d and TMR3d) or seven (Drench7d and TMR7d) days. Follicular dynamics monitoring was performed by ultrasonography and plasma glucose and glutathione peroxidase levels were measured in the third administration of PGF2. The ovulatory rate of all groups was evaluated six days after the final dose of prostaglandin by laparoscopy. Higher glucose levels were observed in the treatment groups compared to the control diet. In groups TMR3d, Drench7d and TMR7d there was a higher proportion (P < 0.001) of large follicles ( 3 < 5 mm); with observation of follicles with size greater than 5 mm. In the same groups a higher number (P < 0.001) of growing follicles (> 3 mm), and a larger size of the larger follicle (P < 0.001) can be registered in the third dose PGF2. In the groups where glycerin was added during 7 days (Drench7d and TMR7d) the ovulation rate showed an increase of 30% in relation to the control group, being also observed a reduction of 38% in the levels of glutathione peroxidase. Based on our findings, the use of glycerin in short term energy supplementation for Morada Nova sheep was successful when supplied for seven days.

Ovelha Santa Inês é mãe de cordeiros quadrigêmeos: relato de caso / Santa Inês ewe is mother of quadruplet lambs: a case report

O presente trabalho teve como objetivo descrever um caso de parto quadrigemelar em uma ovelha da raça Santa Inês. Em abril de 2013, foi atendida, em uma propriedade rural no município de Santa Cruz da Conceição, estado de São Paulo, uma ovelha da raça Sant Inês que havia parido quatro cordeiros. Nasceram três fêmeas, com pelagem marrom, branca e preta, e um macho, com pelagem preta. No período de uma hora após o parto, todos os cordeiros ficaram em pé e mamaram o colostro. A ovelha não rejeitou nenhum dos cordeiros.(AU)

The study aimed to describe a case of Santa Inês ewe having quadruplets. In April of 2013 on a farm in Santa Cruz da Conceição, São Paulo, a Santa Inês sheep that had calved 4 lambs was assisted. There were three females and one male, the females had brown coats, white and black, and the male had a black coat. Within 1 hour after birth all lambs were standing and suckled colostrum. The ewe did not reject any of the lambs.(AU)

Utilização da gonadotrofina coriônica equina (eCG) em protocolos de sincronização da ovulação para IATF em bovinos: revisão / Use of equine chorionic gonadotropin (eCG) in ovulation synchronization protocols for FTAI in cattle: review

O rebanho bovino brasileiro apresenta um grande número de animais com baixo escore de condiçãocorporal e com um grande período de anestro pós-parto, o que contribui notavelmente para a baixa eficiênciareprodutiva do rebanho nacional, uma vez que a condição nutricional do animal e a ciclicidade são fatores queinterferem diretamente no desempenho reprodutivo. Nesse sentido, alguns tratamentos hormonais, associadoscom eCG, têm sido utilizados em rebanhos sob essas condições, a fim de se aumentar a pulsatilidade de LH paracrescimento folicular e sincronização da ovulação. O objetivo desta revisão é apresentar alguns resultados do usode eCG em protocolos para inseminação artificial em tempo fixo em bovinos.(AU)

The Brazilian cattle presents a large number of animals with low body condition score and a largeperiod of postpartum anestrus, which contributes significantly to the low reproductive efficiency of the nationalherd, since the nutritional condition of the animal and the cyclicity are factors that directly affect reproductiveperformance. Thus, some hormonal treatments, associated with eCG, have been used for cattle under theseconditions, in order to increase the LH pulsatility for follicular growth and ovulation synchronization. The aimof this review is to present some results of the use of eCG in protocols for fixed-time artificial insemination incattle.(AU)

Utilização da gonadotrofina coriônica equina (eCG) em protocolos de sincronização da ovulação para IATF em bovinos: revisão / Use of equine chorionic gonadotropin (eCG) in ovulation synchronization protocols for FTAI in cattle: review

O rebanho bovino brasileiro apresenta um grande número de animais com baixo escore de condiçãocorporal e com um grande período de anestro pós-parto, o que contribui notavelmente para a baixa eficiênciareprodutiva do rebanho nacional, uma vez que a condição nutricional do animal e a ciclicidade são fatores queinterferem diretamente no desempenho reprodutivo. Nesse sentido, alguns tratamentos hormonais, associadoscom eCG, têm sido utilizados em rebanhos sob essas condições, a fim de se aumentar a pulsatilidade de LH paracrescimento folicular e sincronização da ovulação. O objetivo desta revisão é apresentar alguns resultados do usode eCG em protocolos para inseminação artificial em tempo fixo em bovinos.

The Brazilian cattle presents a large number of animals with low body condition score and a largeperiod of postpartum anestrus, which contributes significantly to the low reproductive efficiency of the nationalherd, since the nutritional condition of the animal and the cyclicity are factors that directly affect reproductiveperformance. Thus, some hormonal treatments, associated with eCG, have been used for cattle under theseconditions, in order to increase the LH pulsatility for follicular growth and ovulation synchronization. The aimof this review is to present some results of the use of eCG in protocols for fixed-time artificial insemination incattle.

Increasing ovulation quota: more than a matter of energy

Background: Nutritional supplementation before breeding (Flushing) has become a common practice and is a reliable method to improve lambing and twining rates in sheep. The improvement of the body condition of a ewe is reflected in a higher number of ovulatory follicles and is termed "static effect of nutrition". Shorter periods of nutritional supplementation can also affect follicular development in the absence of changes in the body condition and weight of the animal, which is known as "acute effect of nutrition". Studies of follicular development in small ruminants have shown that 4 to 5 follicular waves occur during the estrous cycle, and that waves emerge every 5 to 7 days. However, the selection phase of the follicular wave occurs within 3 to 4 days, thus the length of flushing could last merely the time needed to push follicles over the selection threshold. Review: Here we examined the evidence produced by our research on the minimum length and appropriate timing of nutrient supplementation needed to enhance ovulation rate and prolificacy in sheep. Ewes have follicles ready to reach ovulatory size at any time of the estrous cycle and, when a follicular phase is induced, most show estrus and ovulate within 60 to 80 h. Hence, ovulatory follicles should commit for ovulation shortly after the decline in progesterone if they are to achieve ovulatory competence. We showed that an ultrashort flushing (USF) given as a single administration of a glycogenic substance at the time of prostaglandin-induced luteolysis (Control =1.6 ± 0.06 vs. USF= 2.08± 0.06) or progestin withdrawal (Control =1.64 ± 0.07 vs. USF= 2.41± 0.09) increased ovulation rate (P < 0.01). This increase was associated with elevated glucose and insulin concentrations for 12 h after USF (P < 0.01). However, the diameter of the three largest follicles did not change between the day of flushing and the day of estrus and did not differ between the control and the USF (P > 0.10). The USF could act either by advancing follicle maturation, or by affecting the feedback loop between the ovaries and gonadotrophin secretion. Therefore, we measured mRNA abundance for LH receptor (LHr), 3ß-hydroxysteroid dehydrogenase (3ß-HSD) and P450 aromatase at 0, 12, 24 and 48 h after the start of luteolysis in ewes treated or not with USF. Aromatase mRNA decreased in large follicles 12 h after USF (P < 0.01), with no changes on mRNA for LHr or 3ß-HSD. Further, we observed that the in vitro rumen fermentation and the in vivo glucose plasma concentrations in response to an isoenergetic (1470.83 kcal) single oral drench of glycerol, propylene glycol or molasses differed. The longer time to begin fermentation of glycerol allows for its absorption and its direct use for glucose production in the liver. Molasses was preferably fermented to butyrate, whereas propylene glycol was preferably fermented to propionic acid thus serving as glycogenic substrate. Glycerol and propylene glycol increased glucose and insulin concentrations in vivo, whereas molasses did not, thus the later may not be suitable for the USF. An increase in ovulation rate and prolificacy was also obtained with treatments that cause nutrient redistribution in the animal such as beta adrenergic receptor agonists and bovine somatotropin. Conclusions: We have developed an ultrashort flushing with glycogenic solutions that when applied at luteolysis will increase ovulation rate in sheep. This hyper-acute effect of nutrition caused a reduction in mRNA for P450 aromatase 12 hours after the glycogenic drench. In addition, from our results we can infer that ovine follicles can develop ovulatory capacity within 48 h after being selected when coinciding with the follicular phase.

Genes relacionados à prolificidade em uso de programas de conservação e melhoramento de ovinos.

A prolificidade (número de cordeiros nascidos por ovelhas expostas à reprodução) está relacionada à taxa de ovulação e pode ser considerada como um parâmetro importante no aumento da produtividade. Atualmente, a fenotipagem dessa característica só pode ser avaliada em fêmeas em idade reprodutiva e, em geral, apresenta um custo relativamente alto para espécie. No entanto, esta é uma característica controlada por poucos genes de forma que pode ser factível a implementação de esquemas de seleção por marcadores moleculares. Três genes de efeito principal tem sido considerados para explicar grande parte dos fenótipos de partos múltiplos: GDF9, BMP15 e BMPR1- b. O presente trabalho foi executado de forma a aumentar o conhecimento dos polimorfismos existentes nestes genes em raças localmente adaptadas de ovinos bem como avaliar a possibilidade de aplicar conhecimento adquirido em programas de conservação e melhoramento no Brasil. No primeiro experimento, 252 animais da raça Morada Nova provenientes de testes de desempenho do Programa de Melhoramento genético participativo da raça foram genotipados para presença ou ausência do alelo FecGE do gene GDF9, inicialmente descrito apenas na raça Santa Inês. A referida mutação foi identificada em alta frequência na raça Morada Nova e ela não aparenta estar associada a características de produção/crescimento usadas nos testes de desempenho da raça Morada Nova. No segundo experimento, sequências completas dos genes: BMP15, BMPR1-b e GDF9 foram obtidas por dados de sequenciamento de nova geração de 75 ovinos de diferentes raças provenientes do repositório do Consórcio Internacional do Genoma Ovino (ISGC). Foram identificados um total de 1610 SNPs a partir de dados de sequenciamento de nova geração de 75 genomas ovinos. Pelo menos três SNPs foram identificados na região de exon dos genes BMPR1-b e BMP15, que resultaram em alterações não conservativa de aminoácidos e, portanto, são candidatos imediatos a serem testados em raças com históricos de partos múltiplos. A identificação e seleção destes SNPs serão usadas para compor um painel de baixa densidade para a prolificidade e, depois de validados em raças prolíficas com histórico de parto simples e múltiplos, poderão ser usados para otimizar programas de conservação e melhoramento de ovinos.

The prolificacy (number of lambs per sheep exposed to reproduction) is mainly related to ovulation rate and can be considered as an important parameter in sheep productivity. This phenotype can only be evaluated in reproductive age female and still has a reasonable cost. On the other hand, it is know this trait is controlled by few genes and it might be feasible to implement marker assisted selection scheme. Three major genes have been recognized to explain phenotypes related to litter size: GDF9, BMP15 and BMPR1-b. The objective of the present study was to increase the knowledge of existing polymorphisms in genes related to prolificacy in locally adapted sheep breeds and evaluate its use in conservation and breeding programs in Brazil. In the first experiment it was genotyped, for the FecGE mutation (GDF9), 252 Morada Nova animals who participated in breed performance tests The FecGE mutation is not restricted to Santa Ines breed and it was found in high frequency in Morada Nova sheep. In addition, this mutation does not appear to be associated with production traits used on performance tests of Morada Nova sheep breed. The second experiment was analyze the complete sequence of genes: BMP15, BMPR1-b and GDF9 from 75 sheep of different breeds from the International Consortium repository Genome Ovine (ISGC). It was identified a total of 1610 SNPs from 75 sheep genomes. Three SNPs from BMP15, BMPR1-b genes change in non-conservative amino acid. The identification and selection of these SNPs will be used to develop a low density panel for prolificacy that might be applied to conservation and breeding programs.

Efeito da frequência de amamentação sobre a taxa de ovulação após tratamento com desmame temporário + GnRH, sobre a incidência de luteólise prematura no primeiro ciclo estral pós-parto e sobre o desempenho da progênie de vacas Nelore / Effect of suckling frequency on ovulation rate after temporary weaning + GnRH treatment, incidence of premature luteolysis in the first postpartum estrous cycle, and performance of calves from Nelore cows

Avaliou-se o efeito da restrição na frequência de amamentação sobre o diâmetro folicular no dia 0 (DFOL), sobre a taxa de ovulação (TO), e sobre a incidência de luteólise prematura no primeiro ciclo estral pós-parto (ILP) de vacas Nelore multíparas, em anestro, submetidas à amamentação ad libitum (controle; n= 115) ou amamentação uma vez ao dia (restrito; n= 109), entre os dias -14 e 9 do experimento, e estudou-se o efeito desses tratamentos sobre o peso à desmama da progênie dessas vacas. Induziu-se ovulação com remoção de bezerros entre os dias -2 e 0 e aplicação de 100μg de GnRH no dia 0. Somente animais que ovularam foram mantidos no experimento (n= 125). A ocorrência de luteólise prematura foi avaliada por meio da dosagem da concentração sérica de progesterona nos dias 5 e 9. A TO não foi influenciada pelos tratamentos (55,8 por cento; P>0,1), e as vacas do tratamento restrito apresentaram maior DFOL (10,90±0,26 vs. 10,18±0,21mm; P<0,05) e menor ILP (21,4 por cento vs. 43,5 por cento; P<0,05). Os bezerros do tratamento controle foram mais pesados (162,32±2,08 vs. 155,91±4,12kg; P<0,05). Conclui-se que a restrição na frequência de amamentação em vacas Nelore reduz a ILP, porém com possível efeito negativo no desenvolvimento dos bezerros.(AU)

The effects of restricted suckling on follicular diameter at day 0 (FDDO), ovulation rate (OR), and incidence of premature luteolysis in the first post partum estrous cycle (PLI) of Nelore cows and the effects on weight at weaning (WW) of progenie of these cows were evaluated. Multiparous anestrous postpartum Nelore cows were submitted to ad libitum suckling (control; n= 115) or once-a-day suckling (restricted; n= 109) from days -14 to 9 of the experiment. For both treatments, a temporary calf removal was performed from days -2 to 0, and on day 0 cows received 100μg of GnRH. Only animals that ovulated after GnRH treatment were used in the experiment (n= 125). The occurrence of premature luteolysis was evaluated by dosage of serum progesterone concentrations on days 5th and 9th. The OR was not affected by treatments (55.8 percent; P>0.1), but cows from restricted treatment had larger FDDO at time of GnRH treatment (10.90±0.26 vs. 10.18±0.21mm; P<0.05) and lower PLI (21.4 percent vs. 43.5 percent; P<0.05) than cows from control treatment. Calves from control treatment had higher WW than calves from restricted treatment (162.32±2.08 vs. 155.91±4.12kg; P<0.05). These results indicate that the restriction in frequency of suckling in Nelore cows may decrease the incidence of premature luteolysis in the first postpartum estrous cycle; however, with possible negative effects on calves development.(AU)

Energy supplementation in Santa Inês sheep subjected to estrus induction treatment / Suplementação calórica em ovelhas da raça Santa Inês submetidas à indução do estro sincronizado

The aim of this study was to evaluate the effect of a 20% increase in dietary energy during short-term estrus induction treatment on the reproductive parameters of Santa Inês ewes. Females (n=43) were allocated into two experimental groups according to the amount of energy inclusion in the diet: maintenance diet or maintenance diet plus 20% energy. Ultrasound examinations were performed in order to detect ovulation. To assess sexual behavior, ewes were teased and further mated. Blood samples were collected for the determination of glucose and insulin concentrations. There was no difference (P>0.05) between groups in the following categories: ovulation rate (80.00% vs. 60.00%), largest follicle diameter (6.00 ± 0.20 vs. 5.90 ± 0.60), interval from device removal to ovulation (52.80 ± 14.87 vs. 59.01 ± 8.34 hours), animals in estrus (75.00% vs. 65.21%), interval from device removal to estrus (30.00 ± 15.49 vs. 30.00 ± 13.35 hours) and conception rate (50.00% vs. 21.73%). There were differences (P<0.05) in the concentrations of insulin and glucose. It can be concluded that the 20% increase in energy in the diet during short-term estrus induction treatment did not affect the reproductive parameters studied.

O objetivo deste estudo foi avaliar o efeito do aumento em 20% da energia da dieta durante um protocolo curto de sincronização do estro sobre os parâmetros reprodutivos e metabólicos em ovelhas da raça Santa Inês. As ovelhas (n=43) foram distribuídas em dois grupos experimentais de acordo com a quantidade de energia incluída na dieta, onde foram utilizadas uma dieta de manutenção e uma dieta de manutenção acrescida em 20% de energia. Exames ultrassonográficos foram realizados para detectar a ovulação, bem como o diâmetro dos folículos. Para avaliação do comportamento sexual as ovelhas foram rufiadas. Foram coletadas amostras de sangue para determinação das concentrações plasmáticas de glicose e insulina. Não houve diferença (P>0,05) entre os grupos para: taxa de animais ovulando (80% vs 60%), diâmetro do maior folículo (6,00 ± 0,20 vs 5,90 ± 0,60), intervalo da retirada do implante à ovulação (52,80 ± 14,87 vs 59,01 ± 8,34 horas), animais em estro (75,00% vs 65,21%), intervalo da retirada do implante ao estro (30,00 ± 15,49 vs 30,00 ± 13,35 horas) e taxa de concepção (50,00% vs 21,73%). Houve diferença (P<0,05) nas concentrações de insulina e glicose. Pode-se concluir que o aumento em 20% da energia da dieta durante um protocolo curto de sincronização do estro não alterou os parâmetros reprodutivos.