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Anti-Müllerian hormone (AMH) is produced by the granulosa cells (GCs) of growing follicles and inhibits follicular development. This study aimed to investigate the regulation of the AMH-specific receptor gene (AMHR2) expression in GCs by bone morphogenetic protein 15 (BMP15), BMP4 and growth differentiation factor 9 (GDF9). Their effects on AMHR2 and AMH mRNAs were studied in luteinized human GCs (hGCs) and in ovine GCs (oGCs) from small antral follicles. The effects of BMPs on human AMHR2 and AMH promoter reporter activities were analyzed in transfected oGCs. The in vivo effect of BMP15 on GCs AMHR2 and AMH expression was investigated by using Lacaune and Rasa Aragonesa hyperprolific ewes carrying loss-of-function mutations in BMP15. mRNAs were quantified by real-time RT-PCR. Promoter reporter constructs activities were quantified by the measurement of their luciferase activity. BMP15 and BMP4 enhanced AMHR2 and AMH expression in hGCs and in oGCs whereas GDF9 had no effect. In oGCs, GDF9 increased BMP15 effect on AMH expression. Consistent with these results, BMP15 and BMP4, but not GDF9, enhanced AMHR2 promoter activity in oGCs, whereas GDF9 increased BMP15 effect on AMH promoter activity. Moreover, oGCs from both BMP15 mutant ewes had reduced AMHR2 mRNA levels but unchanged AMH expression compared to wild-type ewes. Altogether, these results suggest that the mechanisms of action of BMP15 on AMHR2 and AMH expression are different, and that by stimulating AMHR2 and AMH expression in GCs BMP15 enhances AMH inhibitory actions in GCs.

En ovino, los retrasos en la edad al primer parto dan lugar a una disminución de la vida productiva del animal, lo que genera importantes pérdidas económicas. En corderas de raza Rasa Aragonesa de 3 meses estimuladas con eCG se ha observado una relación entre la concentración de la hormona Anti-Mülleriana (AMH) y la respuesta ovulatoria con su fertilidad temprana. El objetivo de este trabajo fue relacionar ambos parámetros con la vida productiva de esas corderas (n=73) con AMH ALTA (>=97 pg/ml) o BAJA (=97 pg/ml) or LOW (

Background Predicting the ability of rams to detect, mate and fertilise ewes in oestrus accurately is certainly difficult; however, tests based on clinical examinations have been performed to assess the overall potential capacity of rams to serve and impregnate ewes. Clinical examinations for breeding soundness evaluation were carried out in 897 Rasa Aragonesa (RA) rams from 35 flocks in North-Eastern (NE) Spain. Clinical examinations of head, trunk, limbs and genitals were performed in each ram. Blood samples were collected for a serological study of Brucella ovis. The sheep owners were surveyed regarding the characteristics of the flock, rams’ health history and the management of rams. The clinical alterations found were classified according to severity (mild or severe). Rams were classified as suitable (without lesions or with only mild lesions) or unsuitable (with severe lesions) for breeding depending on the results of the clinical examinations. Results The results showed that 60.6 % of rams presented some type of alteration (mild: 43.3 %; severe: 17.3 %) in various body parts (genitalia: 31.6 %; head and trunk: 37.2 %; limbs: 15.5 %), and that 16.7 % of rams were classified as unsuitable breeders. The most common genital alterations were ulcerative posthitis (18.7 %) followed by testicular lesions (5.3 %). The highest prevalence of unsuitable breeders was found in the category of adult and aged rams (13.8 % and 37.4 %, respectively) and in the category of emaciated rams (33.3 %). All rams examined were seronegative to Brucella ovis. The mean percentage of rams in flocks was 2.8 % (min: 1.6 %; max: 4.6 %); nevertheless, this percentage dropped to 2.5 % (min: 1.4 %; max: 3.7 %) and 2.1 % (min: 0.3 %; max: 3.5 %) when only suitable or effective (suitable mature) rams were considered. Conclusion Thus, it is concluded that there are fewer effective rams in farms than farmers realise. Frequent clinical examination of males is recommended in order to identify potentially infertile rams. Published

Genetic progress for reproductive performance in pigs is limited by mothering ability. It is a critical aspect for dam lines, in which litter weight at weaning could be included with litter size in the selection goal. Our objective was to investigate in Iberian pigs the genetic basis of the number of alive born piglets (NBA) and the litter weight at 21days (LW21) over the successive parities (t). Records for NBA were available from 6,775 litters born from 1,893 sows of the Torbiscal line, and LW21 records proceeded from 1,431 sows and 2,963 litters without crossfostering. Genetic parameters were estimated using an animal model with repeatability, a multi-trait animal model, and a random regression model. Estimated values of heritabilities for NBA and genetic correlations between parities confirm a partially different genetic control of prolificacy at parity 1 and at later parities. Results for LW21 indicate that this trait may be partially controlled by different genes at the first two parities and at the later ones. Estimated genetic parameters for NBA (t = 1), NBA (t >/= 2), LW21 (t /= 3) were: heritability, hE2 = 0.15, 0.12, 0.22 and 0.15, respectively, and coefficient of permanent environmental effects, pE2 = 0.05, 0.02 and 0.24, respectively for the three last traits. The values of genetic correlations ranged from 0.44 to 0.84. A multitrait approach would be useful to estimate accurate genetic parameters, and to improve the low persistency of reproductive performance in the later parities of Iberian sows. La mejora genética de la eficiencia reproductiva en cerdos está limitada por su aptitud maternal. Es éste un aspecto crítico en las líneas maternas, en las que el peso de la camada al destete podría ser incluido junto al tamaño de camada en el objetivo de selección. El objetivo del trabajo fue investigar en cerdos Ibéricos la base genética del número de lechones nacidos vivos (NBA) y el peso de camada a 21 días (LW21) a lo largo de los sucesivos partos (t). Se dispuso de registros de NBA de 6.775 camadas nacidas de 1.893 cerdas, y registros de LW21 procedentes de 1.431 cerdas y 2.963 camadas sin adopciones. Se estimaron parámetros genéticos mediante tres modelos: con repetibilidad, multicarácter y de regresión aleatoria. Los valores de las heredabilidades y las correlaciones genéticas entre NBA en diferentes partos confirman su control genético, parcialmente distinto en el parto primero y posteriores. Los resultados para LW21 indican que este carácter puede estar parcialmente controlado por diferentes genes en los dos primeros partos y en los sucesivos. Los parámetros genéticos estimados para NBA (t = 1), NBA (t >/= 2), LW21 (t /= 3) fueron: heredabilidad, hE2 = 0,15, 0,12, 0,22 y 0,15, respectivamente, y coeficiente de efectos de ambiente permanente, pE2 = 0,05, 0,02 y 0,24, respectivamente para los tres últimos caracteres. El rango de las correlaciones genéticas fue de 0,44 a 0,84. Un enfoque genético multicarácter sería útil para estimar parámetros genéticos precisos y mejorar la escasa persistencia del rendimiento reproductivo en los últimos partos.

This study describes the effectiveness of a method to synchronize ovulation in Spanish ibex for artificial insemination, based on one previously described for use in domestic goats. Estrus and ovulation were synchronised in eight adult ibex females (aged 3-5 yr old) during the breeding season (January) by intramuscular injection of 25 mg of progesterone in olive oil plus an 100 microg intramuscular of cloprostenol on day 0 followed by a single dose of 100 microg cloprostenol intramuscular 9 days later (day 10). Ibexes were inseminated by laparoscopy with 200 x 10E6 spermatozoa at 52h after the second cloprostenol injection. Two of the eight treated ibex (25%) conceived and carried their pregnancies to term. The protocol described here minimizes animal handling (in contrast to synchronization methods utilizing intravaginal progestins and equine chorionic gonadotropin injections), which greatly facilitates the application of reproductive technologies in Spanish ibex captive breeding programs. El presente estudio describe la efectividad de un método de sincronización de la ovulación en la cabra montés, para su uso en inseminación artificial, basado en una metodología previamente descrita en la cabra doméstica. El celo y la ovulación fueron sincronizados en ocho cabras monteses adultas (3-5 años de edad) durante la estación reproductiva (enero), mediante la administración intramuscular de 25 mg de progesterona vehiculada en aceite de oliva más 100 microg de cloprostenol intramuscular en el día 0, seguido de otra inyección de 100 microg de cloprostenol intramuscular 9 días después (día 10). Las cabras monteses fueron inseminadas mediante laparoscopia con 200 x 10E6 espermatozoides, a las 52h después de la segunda inyección de cloprostenol. Dos de las ocho cabras tratadas (25%) quedaron gestantes y llevaron a término su gestación. El protocolo descrito minimiza la manipulación de los animales (en contraste con métodos de sincronización basados en progestágenos intravaginales y la administración de gonadotropina coriónica equina), lo que facilita en gran medida la aplicación de tecnologías reproductivas en programas de reproducción de cabras monteses en cautividad.

The effects of a supplemental feeding strategy during mid-gestation on lean gilts body reserves, productive and reproductive performance were assessed. A total of 90 gilts were allocated into two treatments (Control, C, and Supplemented, S). Control sows (n = 43) were fed according to the level routinely used on farm (2.5-3.0 kg d-1, 2.9 Mcal metabolizable energy kg-1 feed and 0.6% of lysine) throughout gestation, and S sows (n = 47) received 50% more feed from day 45 to day 85 of gestation. Body weight (BW) and sows body condition [backfat (BF), loin depth and body condition score] were recorded on days 40 and 80 of gestation, at farrowing and at weaning. Litter performance at birth and on day 18 ± 1 of lactation was registered at first and second parities. Although no differences in backfat levels were found at weaning, a higher proportion of S sows stayed within the target backfat interval both at farrowing (17-21 mm) and at weaning (> 14 mm). No differences were found in BW and body reserves losses during lactation between treatment groups. Litter weight at birth tended to be higher in the S group of sows, consistently, in the first and second parities (P < 0.10), compared to the C group. Thus, providing an extra feed allowance during mid-gestation has beneficial effects on gilts' body fat reserves at weaning (higher proportion of sows in the optimum BF interval) and slight advantages on productive output, although probably not high enough to justify the extra feed wastage. Evaluaron los efectos de un incremento del nivel de alimentación en gestación media sobre las reservas corporales y los rendimientos productivos de cerdas nulíparas magras. Un total de 90 cerdas fueron distribuidas en dos tratamientos (Control, C, y Suplementado, S). Las cerdas C (n = 43) se alimentaron según el patrón de alimentación habitual en granja en gestación (2,5-3,0 kg d-1, 2,9 Mcal energía metabólica kg-1 de pienso y 0,6% de lisina). Las cerdas S (n = 47) recibieron un 50% más de alimento entre los días 45 y 85 de gestación. El peso vivo (BW), espesor de grasa dorsal (BF), profundidad de lomo y nota de condición corporal de las cerdas se midieron a los 40 y 80 días de gestación, al parto y al destete. Los rendimientos al nacimiento y el día 18 ± 1 de lactación fueron registrados en los dos primeros partos. Aunque no hubo diferencias en el nivel de BF al destete, hubo una mayor proporción de cerdas S dentro del intervalo de BF óptimo al parto (17-21 mm) y al destete (> 14 mm). No se encontraron diferencias entre tratamientos en las pérdidas de BW y reservas corporales en lactación. El peso medio de camada al nacimiento resultó mayor en las cerdas S (P < 0,10) en los dos partos estudiados. En conclusión, un aporte extra de alimento durante la gestación media resultó en beneficios sobre las reservas grasas de cerdas nulíparas al destete, y en un ligero pero positivo efecto en los rendimientos productivos, aunque éstos difícilmente compensan el aporte extra de alimento.

A global analysis of several productive indicators and the postpartum anoestrous interval (PPI) of 549 beef cowswas carried out to determine the management factors related with postpartum ovarian reactivation in extensive mountainfarming systems. Multivariate statistic methods (Multiple Correspondence Analysis and Cluster Analysis) were usedto analyse the data due to the multifactorial nature of the processes involved. PPI was associated to four factors thatexplained 59% of the total inertia of the sample and were defined as follows: «Prepartum feeding level» (19% of theinertia), «Postpartum feeding level-Parity» (16.4%), «Suckling frequency» (13%) and «Calving difficulty» (10.5%).These factors were introduced into a Cluster Analysis that identified five types of cows: «Primiparous cows», «Twicedailysuckling», «Ad libitum suckling-Brown Swiss», «Autumn calving season» and «Spring calving season». Cowbreed was not related to PPI, although the Cluster Analysis associated the suckling-induced prolonged PPI with BrownSwiss animals. In Brown Swiss breed, PPI was longer in the spring than in the autumn due to nutritional differencesrather than to a seasonal effect. Autumn calving was better adapted to dry mountain conditions., Para determinar los factores de explotación relacionados con la reactivación ovárica postparto en vacas nodrizas se realizó un análisis global de la serie de indicadores productivos y la duración del anestro postparto (APP) de 549 vacas explotadas en condiciones extensivas. Debido a la naturaleza multifactorial del proceso en estudio se eligió la metodología estadística multivariante (Análisis Factorial de Correspondencias Múltiples y Análisis Cluster). La duración del APP estuvo asociada a cuatro factores que explicaron el 59% de la heterogeneidad inicial de la muestra y que se definieron como : "Alimentación preparto" (19% de la inercia), "Alimentación postparto-Edad" (16.4% ), "Manejo del ternero" (13% ) y "Dificultad al parto" (10.5% ). Estos factores se introdujeron en un Análisis Cluster que identificó cinco grupos de vacas con características productivas y reproductivas diferentes, y que denominamos como "Primíaras", "Acceso restringido", "Acceso Libre-Parda de Montaña", "Parto de otoño" y "Parto de primavera" (...)

This paper reports two experiments, the aims of which were to contribute to the development of the single farrowing production system for pigs. The first reports the induction of oestrus in three groups of 70 Duroc gilts (167 days old, body weight 93.6 kg) via the injection of either 1000, 600 or 400 IU of pregnant mare serum gonadotrophin (PMSG) plus 500, 200 or again 200 IU of human chorionic gonadotrophin (hCG) respectively. No significant differences were observed among these treatments with respect to the percentage of gilts entering oestrus, their fertility or their prolificacy. The average number of piglets weaned per farrowed gilt was 5.61, 5.66 and 6.69 (P < 0.05) while the number of pigs weaned per induced gilt was 2.33, 2.67 and 3.34 respectively (P < 0.05). The second experiment, designed to analyse carcass quality, involved 30 Duroc gilts aged 167 days and weighing 93.9 kg. Ten empty gilts were slaughtered at 197 days and at a mean weight of 112.1 kg, another 10 in which oestrus was induced with PG-600 —but which were not allowed to nurse their piglets— were slaughtered 4 days after farrowing and at a mean of 136.9 kg, and the remaining 10, which nursed their young, were slaughtered 10 days after a 21 day lactation period and at a mean body weight of 135.4 kg. The average daily weight gain during gestation was 0.418 kg. Weight loss during lactation was 0.159 kg day -1 . The mean weight of the pigs at birth, when weaned and at 60 days post-weaning was 1.28, 4.5 and 18.2 kg respectively. The carcass length, carcass yield and the back fat thickness of the farrowing but non-nursing and the nursing gilts were significantly higher (P < 0.05) than those of the empty gilts. The weight of their hams and forelegs were, however, lower with respect to overall carcass weight (P < 0.05). Additional key words: gilts, induction of oestrus, productive results. Resumen Resultados productivos del sistema de manejo a un solo parto en ganado porcino