Efeito do rubor no desempenho reprodutivo em ovelhas de cabelo em um centro de apoio à pesquisa e ensino no México

Sheep production is an important change in the livestock economy in Mexico, the quality can be improved with the implementation of nutritional and biotechnological strategies. This study evaluated the effect of flushing in sheep with medium body condition (CCM) or Low (CCB) body condition on reproductive performance in a Research and Teaching Support Center in Mexico. A group of 42 multiparous sheep of Pelibuey, Dorper, Hampshire, East Friesian and Damara breeds assigned to 4 treatments T1: (N = 10 CCM with flushing), T2: (N = 9 CCM without flushing), T3: (N = 12 CCB with flushing), T4: (N = 11 CCB without flushing). The washing consists of a diet based on sorghum (Crude Protein: 14.76), weights (before, during and after the experiment). It is synchronized with a CIDR®, with withdrawal on day 9 and detected the estrus and immediate natural riding. On day 7, 1 mL of Lutalyse® (7.5 mg PGF2α) was applied. The rate of ovulation and pregnancy by ultrasonography at day 45 and 75 was evaluated, prolificity and fertility were also measured. The weighing averages were: before rinsing T1: 49.08; T2: 49.15; T3: 54.46 and T4: 52.43, during washing T1: 48.12; T2: 47.08; T3: 55.06 and T4: 50.56 and after discharge T1: 49.42; T2: 49.11; T3: 55.00 and T4: 53.63. The total averages for the 3 weighings were P1 = 51.28; P2 = 50.21; P3 = 51.79. Regarding reproductive variables, no statistically determined differences were found by means of a Z test; however, the proportions of the data that change the differences between treatments, such as: in the presentation of the estrus of T1, T3 and T4 (90, 100 and 90.4% respectively) versus T2 (55.5%); in pregnancy, T1 (60%) versus T2, T3 and T4 (44.4, 41.7 and 10% respectively) and regarding prolificacy, T1, T3 and T4 had a greater number of offspring/sheep (0.80, 1.00 and 0.90 respectively) with respect to T2 (0.33). The use of rinsing in animals with CCB and CCM before the mountain or during synchronization with pharmacological methods improves fertility; but it is important to continue supplying protein requirements to improve fertility, reduce neonatal deaths and improve the weight at birth of sheep.La producción ovina es un renglón importante de la economía pecuaria en México, la cual puede ser mejorada con la implementación de estrategias nutricionales y biotecnológicas. Este estudio evaluó el efecto del flushing en ovejas con condición corporal media (CCM) o baja (CCB) sobre el desempeño reproductivo en un centro de apoyo a la investigación y docencia en México. Se seleccionó un grupo de 42 ovejas multíparas de razas Pelibuey, Dorper, Hampshire, East friesian y Damara asignadas a 4 tratamientos T1: (N = 10 CCM con T2:  CCB¿=)(/^*ÑCA) y Baja (CCB)peci en Mexico-Ceisaflushing), T2: (N = 9 CCM sin flushing), T3: (N = 12 CCB con flushing), T4: (N = 11 CCB sin flushing). El flushing consistió en una dieta basada en sorgo (proteína cruda: 14.76), se realizaron pesajes (antes, durante y después del experimento). Se sincronizaron con un CIDR®, con retiro al día 9 y detectado el estro y monta natural inmediata. Al día 7 se aplicó 1 mL de Lutalyse® (7.5 mg PGF2α). Se evaluó la tasa de ovulación y gestación por ultrasonografía al día 45 y 75, igualmente se midió la prolificidad y fecundidad. Las medias de los pesajes fueron: antes de flushing T1: 49.08; T2: 49.15; T3: 54.46 y T4: 52.43, durante flushing T1: 48.12; T2: 47.08; T3: 55.06 y T4: 50.56 y post flushing T1: 49.42; T2: 49.11; T3: 55.00 y T4: 53.63. Las medias totales para los 3 pesajes fueron P1 = 51.28; P2 = 50.21; P3 = 51.79. En cuanto a las variables reproductivas no se encontraron diferencias estadísticamente significativas por medio de una prueba de Z; sin embargo las proporciones de los datos obtenidos muestran diferencias entre tratamientos, como los son: en la presentación del estro de los T1, T3 y T4 (90, 100 y 90.4% respectivamente) frente al T2 (55.5%); en la gestación el T1 (60%) frente a T2, T3 y T4 (44.4, 41.7 y 10% respectivamente) y respecto a la prolificidad los T1, T3 y T4 tuvieron un mayor número de crías/oveja (0.80; 1.00 y 0.90 respectivamente) respecto al T2 (0.33). El uso del flushing en animales con CCB antes de la monta o durante la sincronización con métodos farmacológicos mejora la fertilidad; pero es importante seguir supliendo los requerimientos de proteína para mejorar la fecundidad, disminuir las muertes neonatales y mejorar el peso al nacimiento de los borregos.A produção ovina é uma linha importante da economia pecuária no México, que pode ser melhorada com a implementação de estratégias nutricionais e biotecnológicas. Este estudo avaliou o efeito do rubor em ovelhas com condição corporal média (CCM) ou Baixa (CCB) sobre o desempenho reprodutivo em um Centro de Apoio ao Ensino e Pesquisa no México. Um grupo de 42 ovelhas multíparas das raças Pelibuey, Dorper, Hampshire, East Friesian e Damara atribuídos a 4 tratamentos T1: (N = 10 CCM com flushing), T2: (N = 9 CCM sem flushing), T3: (N = 12 CCB com descarga), T4: (N = 11 CCB sem descarga). A lavagem consistiu de dieta à base de sorgo (proteína bruta: 14,76), sendo realizadas pesagens (antes, durante e após o experimento). Foram sincronizados com CIDR®, com retirada no 9º dia e detecção do estro e montagem natural imediata. No dia 7, foi aplicado 1 mL de Lutalyse® (7.5 mg PGF2α). A ovulação e a taxa de gestação foram avaliadas por ultrassonografia nos dias 45 e 75, e a prolificidade e a fertilidade também foram medidas. As médias das pesagens foram: antes da lavagem T1: 49.08; T2: 49.15; T3: 54.46 e T4: 52.43, na lavagem T1: 48.12; T2: 47.08; T3: 55.06 e T4: 50.56 e T1 pós-lavagem: 49.42; T2: 49.11; T3: 55.00 e T4: 53.63. As médias totais das 3 pesagens foram P1 = 51.28; P2 = 50.21; P3 = 51.79. Em relação às variáveis ​​reprodutivas, não foram encontradas diferenças estatisticamente significativas por meio do teste Z; Porém, as proporções dos dados obtidos mostram diferenças entre os tratamentos, tais como: na apresentação do estro em T1, T3 e T4 (90, 100 e 90.4% respectivamente) versus T2 (55.5%); na gestação, T1 (60%) em relação a T2, T3 e T4 (44.4, 41.7 e 10% respectivamente) e quanto à prolificidade, T1, T3 e T4 tiveram maior número de filhos/ovelhas (0.80, 1.00 e 0.90 respectivamente) com em relação a T2 (0.33). O uso de lavagem em animais com CBC antes do acasalamento ou durante a sincronização com métodos farmacológicos melhora a fertilidade; mas é importante continuar atendendo aos requisitos de proteína para melhorar a fertilidade, reduzir as mortes neonatais e melhorar o peso ao nascer das ovelhas

Degradabilidade da matéria seca e da proteína bruta de frutos de Cloroleucon mangense e Acacia cochliacantha em carneiros

The objective of this work was to determine the nutritional content and the degradability of the dry matter and protein of fruits of Chloroleucon mangense and Acacia cochliacantha and of a 1:1 mixture of both, offered as supplements to Rambouillet sheep. In situ ruminal degradation was evaluated in three adult rams, fitted with a rumen cannula, with different incubation times of 0, 6, 12, 24, 48, and 72 hours. Protein intestinal degradability was quantified with a three-step procedure: in situ ruminal incubation, in vitro enzymatic digestion, and abomasal-intestinal digestion. The fruits of C. mangense and A. cochliacantha contain 21 and 12% crude protein, 47 and 56% neutral detergent fiber, 31 and 43% acid detergent fiber, and 0.9 and 6.0% condensed tannins, respectively. The fruits of C. mangense showed a higher nutritional value and a higher  dry matter and crude protein degradability (p<0.05) than those of A. cochliacantha and the 1:1 mixture. The amount of protein that reaches the small intestine is higher for the 1:1, which is an indicative that its tannin concentration is enough to increase the bypass protein that can be absorbed in the small intestine.O objetivo deste trabalho foi determinar o conteúdo nutricional e a degradabilidade da matéria seca e da proteína de frutos de Cloroleucon mangense e Acacia cochliacantha e de uma mistura 1:1 de ambos, oferecidos como suplementos para carneiros Rambouillet. Foi avaliada a degradação ruminal in situ em três carneiros adultos, com colocação de uma cânula ruminal, com diferentes tempos de incubação de 0, 6, 12, 24, 48 e 72 horas. A degradação intestinal da proteína foi quantificada por meio de procedimento com três etapas: incubação ruminal in situ, digestão enzimática in vitro e digestão abomasal intestinal. Os frutos de C. mangense e A. cochliacantha contêm 21% e 12% de proteína bruta, 47% e 56% de fibra em detergente neutro, 31 e 43% de fibra em detergente ácido e 0,9 e 6,0% de taninos condensados, respectivamente. Os frutos de C. mangense apresentaram valor nutricional edegradabilidade da matéria seca e da proteína bruta (p<0,05) maiores que os de A. cochliacantha e da mistura 1:1. A quantidade de proteína que chega ao intestino delgado é maior para a mistura 1:1, o que é indicativo de que sua concentração de tanino é suficiente para aumentar a proteína não degradável no rúmen absorvida no intestino delgado

Suckling and Excess Fat in the Postpartum Reproductive Activity of Hair Sheep

Objective: To evaluate the effect of excess fat and suckling control on postpartum reproductive activity of hair ewes. Design/Methodology/Approach: Eighty-one (81) hair ewes with average weight of 58±8 kg were used, which on postpartum day 7 were assigned to one of four treatments under a completely randomized design with 2×2 factorial arrangement. Factor A is the type of suckling [continuous suckling (CS) and suckling control (SC)] and factor B, excess fat (with or without). In CS, ewes remained with their offspring 24 hours a day (n=16). In continuous suckling plus fat (CSF), ewes remained with the offspring all day plus the addition of 8% in dietary fat (n=24). In SC, it was 30 min of suckling only twice per day (n=14). In suckling control plus fat (SCF), controlled suckling lasted 30 min, twice a day plus 8% fat (n=25). Results: The response to the treatments was similar (p &gt; 0.05) in onset of estrus, return rate, gestation, prolificacy and fertilization; for the lambing rate variable, there were differences (p ≤ 0.05), the SCF treatment was higher (68%) compared to CS (50%) and CSF (50%), but equal (p &lt; 0.05) to SC (57.1%). Implications: In this experiment, it was observed that the SCF treatment presented a better response, implying that controlling suckling and providing excess fat helps to restore ovarian activity sooner after lambing. Conclusions: Suckling control plus inclusion of dietary excess fat in ovulation induction protocols during early postpartum (around day 25 postpartum) can be included in routine reproductive management of flocks, improving the reproductive efficiency of hair sheep

Reproductive performance of hair sheep under different body conditions and feeding levels

O objetivo deste trabalho foi avaliar o efeito da interação entre nível de alimentação (FL) e escore de condição corporal (BCS) sobre os parâmetros reprodutivos de ovelhas de pelo Pelibuey (Ovis aries). As unidades experimentais (64 ovelhas) foram distribuídas aleatoriamente a um dos quatro tratamentos: baixo nível de alimentação e baixo escore de condição corporal; alto nível de alimentação e baixo escore nas condições corporais; baixo nível de alimentação e alto escore nas condições corporais; e alto nível de alimentação e alto escore nas condições corporais. O efeito do escore de condição corporal de ovelhas foi significativo sobre as taxas de prenhez e parto. O efeito do nível de alimentação foi significativo sobre as taxas de ovulação, retorno do estro, prenhez e prolificidade. O efeito da interação entre escore de condição corporal e nível de alimentação foi significativo sobre as taxas de ovulação, retorno do estro, prenhez, parto e prolificidade. A função reprodutiva é mais sensível aos melhores efeitos nutricionais em ovelhas com baixo escore de condição corporal.The objective of this work was to evaluate the effect of the interaction between feeding level (FL) and body condition score (BCS) on the reproductive parameters of Pelibuey hair sheep (Ovis aries). The experimental units (64 ewes) were randomly assigned to one of four treatments: low feeding level and low body condition score; high feeding level and low body condition score; low feeding level and high body condition score; and high feeding level and high body condition score. The effect of sheep body condition score was significant on the pregnancy and lambing rates. The effect of feeding level was significant on the ovulation, estrus returning, pregnancy, and prolificacy rates. The interaction effect between BCS and FL was significant on the ovulation, estrus returning, pregnancy, lambing, and prolificacy rates. The reproductive function is more sensitive to the better nutrition effects in sheep with a low body condition score

Duration of estrus and preovulatory surge of LH in Boer x Nubian goats synchronized with various hormones in tropical latitude of Mexico

The objective was to determine the duration of estrus, preovulatory surge of luteinizing hormone (LH), fertility and prolificacy of Boer x Nubian goats in tropical Mexico (19º29’LN) synchronized with fluorogestone acetate (FGA) and prostaglandin F2 (PGF2) combined with gonadotrophin-releasing hormone (GnRH) or equine chorionic gonadotrophin (eCG). The treatments were: T1 (FGA, n = 5), T2 (FGA + GnRH, n = 7), T3 (FGA + eCG, n = 8), T4 (PGF2 + GnRH, n = 5) and T5 (PGF2 + eCG, n = 7). The responses measured were percentage of animals showing estrus, duration of estrus (h), fertility (%), prolificacy (kids/parturition); intervals (h) from end of treatment til estrus and til peak preovulatory LH concentration, from onset of estrus til peak LH; duration of peak LH (h), and LH concentration (ng/mL). Duration of estrus was longest in goats of T3 (35.2 ± 1.4). Onset of estrus differed (P&lt;0.05) between T2 and T3 (27.9 ± 1.2 vs. 17.2 ± 1.2). Use of PGF2 (T4 and T5) delayed onset of estrus compared with T2 and T3. Interval between sponge withdrawal and onset of LH peak was shorter in T3 than T2 (P&lt;0.05), while that from onset of estrus to LH peak was shorter (P&lt;0.05) with eCG, injection than with GnRH. There were no differences in length and breadth neither of the preovulatory LH surge nor in fertility or litter size (P&gt;0.05). The use of GnRH, either with PGF2 or FGA, increased the time from onset of estrus to LH peak, whereas the use of eCG shortened it

Evaluation of seminal characteristics of Pelibuey and East Friesian rams at two different times of the year

Objective: To determine the changes in seminal quality of Pelibuey and East Friesian rams during the non-breeding (long days; March-June) and breeding seasons (short days; September-December) at 19° north latitude. Design/methodology/approach: To determine changes in seminal quality over time, seminal parameters of rams, collected with an artificial vagina were evaluated over 32 weeks. An analysis of variance was performed with a completely randomized design in a 2 x 2 factorial arrangement (breed and season). Results: No differences were found within breeds or between breeds in the same season in the evaluated seminal parameters; however, differences were reported between seasons in the live weight parameters, lower in the non-reproductive season, in addition to an increased scrotal circumference and mass motility during the reproductive season. Study limitations/implications: Semen parameters estimation, in field trials, is subjective compared to computerized semen evaluation systems, it is therefore desirable to have extensive experience in semen evaluation at the field level before starting the study. To confirm the results obtained in this study, a new experiment with a larger number of experimental units is suggested. Findings/conclusions: It is concluded that in the environmental and management conditions, where the seminal evaluation took place, no differences were found between breeds, suggesting that the Pelibuey and East Friesian breeds at 19° north latitude do not decrease their seminal parameters during the non-breeding season compared to the breeding season. This suggest that these two sheep breeds are able to reproduce, in such conditions, all year round

Resposta reprodutiva de ovelhas Pelibuey à aplicação de somatotropina bovina recombinante e de um reconstituinte metabólico

The objective of this work was to evaluate the effect of recombinant bovine somatotropin (rBST) and of the metabolic restorative preparation Metabolase (MR) on the reestablishment of the post-partum ovarian activity of Pelibuey sheep. Ninety-four ewes, with their respective lambs, were randomly assigned to one of the following treatments: T1, continuous suckling (CS); T2, CS + MR; T3, CS + rBST; and T4, CS + MR + rBST. Ovulating percentages, weight changes in ewes and lambs, incidence of estrus, onset and return to estrus, calving, fecundity, and prolificacy were evaluated. The highest ovulation percentages were recorded for CS in T1 and T2, and the lowest ones for rBST in T3 and T4. The treatments had a significant effect on lamb weight. Ewes in T3 had the lowest incidence of estrus (52.9%), besides a greater onset (26.8±1.9 hours) and return to estrus (66.6%). Calving (86.2%) and fecundity (1.8±0.2) were significantly higher in T2. The application of rBST in ewes increases lamb body weight, due to increased milk production, but affects negatively post-partum reproductive activity due to the loss of ewe body weight.O objetivo deste trabalho foi avaliar o efeito da somatotropina bovina recombinante (rBST) e do reconstituinte metabólico Metabolase (MR) no reestabelecimento da atividade ovariana pós-parto de ovelhas Pelibuey. Noventa e quatro ovelhas, com seus respectivos cordeiros, foram distribuídas ao acaso a um dos seguintes tratamentos: T1, amamentação continua (AC); T2, AC + MR; T3, AC + rBST; e T4, AC + MR + rBST. Foram avaliados percentagem de ovulação, alterações de peso em ovelhas e carneiros, incidência do estro, início e retorno ao estro, parição, fecundidade e prolificidade. As maiores percentagens de ovulação foram registradas para AC em T1 e T2, e as menores para rBST em T3 e T4. Os tratamentos tiveram efeito significativo sobre peso dos cordeiros. As ovelhas em T3 apresentaram menor incidência de estro (52,9%), além de maior início (26,8±1,9 horas) e retorno ao estro (66,6%). A parição (86,2%) e a fecundidade (1,8±0,2) foram significativamente maiores em T2. A aplicação da rBST nas ovelhas incrementa o peso corporal dos cordeiros, em razão do aumento na produção de leite, mas afeta negativamente a atividade reprodutiva pós-parto, em razão da perda de peso corporal das ovelhas

Involvement of the Interferon Tau Gene in Maternal Recognition of Gestation in Sheep

Objective: The aim of this review was to describe the implications of the interferon tau gene in the maternal recognition of pregnancy in sheep. Design / methodology / approach: A search and an analysis of the scientific documents retrieved from the Web of Science and Scopus databases related to the functions of the interferon tau gene in the maternal recognition of pregnancy in sheep were carried out. Results: Interferon tau (IFNt) gene participates in the maternal recognition of pregnancy to prevent possible rejection of the embryo and supports the secretion of progesterone that intervenes in the preparation of the endometrium for implantation; In addition, it inhibits the mobility of the myometrium to maintain pregnancy. IFNt stimulates the transcription of so-called interferon-stimulated genes (ISG) that are the effectors of autonomous antiviral defense in cells. One of the representative ISG members is the interferon 15-stimulated gene (ISG15) that regulates endometrial receptivity at implantation, as well as concept survival, growth, and development. Implications: Most embryonic losses occur between fertilization and maternal recognition of pregnancy. Understanding this topic is essential to understand the possible causes of early pregnancy losses. Conclusions: Considerable progress has been made in the discovery of how the IFNt and ISG15 genes act in maternal recognition of pregnancy in sheep. However, some of the regulatory mechanisms involved remain to be understood.Objective: To describe the involvement of the interferon tau gene in the maternal recognition of pregnancy in sheep. Design/Methodology/Approach: A search and analysis of the scientific documents retrieved from the Web of Science and Scopus databases related to the functions of the interferon tau gene in the maternal recognition of pregnancy in sheep were conducted. Results: The interferon tau gene (IFNτ) participates in maternal recognition of pregnancy to avoid possible rejection of the embryo, and supports the secretion of progesterone involved in preparing the endometrium for implantation; it also inhibits myometrial motility to maintain pregnancy. IFNτ stimulates the transcription of so-called interferon-stimulated genes (ISGs), which are the effectors of cell-autonomous antiviral defense.  One of the representative members of ISGs is the interferon 15-stimulated gene (ISG15) which regulates endometrial receptivity at implantation, as well as survival, growth and development of the conceptus. Study Limitations/Implications: Most embryonic losses occur between fertilization and maternal recognition of pregnancy. Understanding this issue is essential to understanding the possible causes of early pregnancy losses. Findings/Conclusions: Considerable progress has been made in the discovery of how the IFNτ and ISG15 genes act in maternal recognition of gestation in shee

The native turkey (Meleagris gallopavo): male morphophysiology

Objective: To describe the morphophysiology and reproductive characteristics of the male turkey. Methodology: An analysis based on the practical experiences from over 10 years with the native Mexican turkey was developed and complemented with literature reports. Results: In Mexico the production management is customs based on traditions and beliefs. In their reproductive morphophysiology, the epididymis absence stands out, as well as a rapid testicular growth during the breeding season, which is controlled by the photoperiod. Limitations of the study: Native turkey farming is practiced in backyard, in marginalized and low-resource areas that have no strategies (nutritional and reproductive) to improve their production. Conclusions: The anatomical, morphological, physiological and reproductive characteristics of the native Mexican turkey were documented. The knowledge on these characteristics will allow to develop feeding and reproductive strategies to improve the productive and reproductive performance of the native turkey and preserve their genetic resources