Utilización de pulseras electrónicas para la identificación de pequeños rumiantes

Se ha comprobado la eficacia de una pulsera electrónica (PATUFLEX) para la identificación de ovinos y caprinos. Se ha estudiado, en primer lugar, el efecto del sistema de explotación sobre el porcentaje de retención de los dispositivos en pruebas de un año de duración. Se seleccionaron explotaciones españolas y francesas con un manejo y unas condiciones medioambientales muy diferentes. Un rebaño ovino en régimen de explotación intensivo con estabulación permanente y un rebaño caprino explotado bajo un sistema ultraextensivo, con pastoreo diario y subida al puerto de montaña en verano en España, y 10 ganaderías francesas de caprino lechero en régimen intensivo. El dispositivo ha mostrado una eficacia de entre el 99,1 y el 100% a los 12 meses en el caso de los rebaños estabulados, mientras que en el rebaño extensivo la prueba se dio por finalizada a los 3 meses con un porcentaje de retención del 94% y de lecturas del 78%. Las lecturas dinámicas fueron del 100% en todos los casos. Esta prueba confirma la influencia del sistema de explotación (estabulación vs. pastoreo en zonas difíciles) sobre la utilidad de este tipo concreto de dispositivo. Los resultados de la prueba realizada en la explotación extensiva han servido para introducir varias modificaciones en la pulsera, con el objetivo de mejorar su rendimiento bajo estas condiciones, lo que ha llevado a la modificación de su diseño con el fin de alcanzar los niveles de retención y lectura exigidos. En segundo lugar, se ha estudiado el desarrollo corporal, a través del peso vivo, y del perímetro del metatarso derecho, lugar donde se colocan las pulseras electrónicas para la identificación electrónica, en cabritas y corderas de reposición de las razas Murciano-Granadina, Saanen, Alpina y Rasa Aragonesa de 5 meses de edad. Mientras que a esa edad el peso vivo de los animales alcanza valores cercanos al 40% en las cabritas y al 60% en las corderas, los perímetros del hueso caña medidos están entre el 80 y el 90%, dependiendo de la raza. Esta diferencia de desarrollo en la extremidad permite colocar este tipo de dispositivos a la edad indicada en la legislación, que son los 6 meses, sin que por ello peligre, por un lado, su permanencia en la pata, y por otro, estrangule la extremidad en el futuro, al haberse alcanzado ya el desarrollo adecuado. Por último, se ha evaluado la capacidad de lectura de los dispositivos en lecturas dinámicas, comprobándose una eficiencia del 100% en todos los casos

How pigs influence indoor air properties in intensive farming: Practical implications - A review

Indoor environmental conditions in intensive pig farms are influenced by both the outdoor air temperature and humidity, and the heat, moisture and gas exchanges between the animal and the air. As ventilation rate in pig facilities is usually estimated in temperature, moisture and even CO2 balances, estimation of heat losses or gains, and moisture and CO2 production from the animal is needed, but the contribution of other sources of the barn, such as slurry or wet surfaces have also to be taken into account. Some recent studies have been conducted to update total heat and moisture production at farm level, showing that current, historical standards of latent heat transfer are consistently lower than those reported recently at facility level, for both adult and growing animals. Also, CO2 production needs to be updated by including an estimation of its release from slurry. These new values will help with updating the standards for ventilation rate recommendations and design of the modern intensive pig buildings

Meta-analysis of the efficacy of melatonin implants for improving reproductive performance in sheep

To evaluate the efficacy of melatonin implants on increasing the production of lambs, a meta-analysis was performed based on the results of 139 experiments carried out in Spain and published in 56 scientific publications or conference proceedings. To assess the effects on fertility, the relative risk (RR) was calculated and, in the case of prolificacy and fecundity, the analysis was based on raw mean difference (D) and the standardized difference between means (d) and their corresponding confidence intervals. In addition, the experiments were stratified by the productive aptitude of the flocks, breed, time of year, and age. For fertility, the mean RR was 1.29, which indicated that the treatment with melatonin increased significantly (by 29%) the probability of pregnancy. For prolificacy, overall D was 0.08 (d = 0.9089); i.e., the groups treated with melatonin increased their litter size by 0.08 lambs/lambing relative to the control groups. Ultimately, treatment with melatonin increased fecundity significantly (0.25 extra lambs/ewe treated) (d = 6.3188), and this trend was evident in all of the stratified datasets. In all cases, there was significant (p < 0.001) heterogeneity and bias. In conclusion, in Spain, melatonin implants had a significant effect on the probability that a ewe became pregnant, increased the number of lambs born per lambing, which ultimately increased the number of lambs born per treated ewe. In addition to confirm the results of previous descriptive reviews in the scientific literature, the metaanalysis made use of a statistical tool that synthesizes and estimates more precisely the effect of this hormone on sheep reproduction. Se ha realizado un meta-análisis sobre la eficacia del uso de implantes de melatonina en ovino en España, analizando los resultados de 139 experiencias publicadas en 56 publicaciones o comunicaciones. Para la fertilidad se han calculado los riesgos relativos (RR) y para la prolificidad y fecundidad se han calculado la diferencia no estandarizada o bruta entre medias (D) y la diferencia estandarizada entre medias (d). Los resultados se han estratificado por aptitud productiva de los rebaños, raza, época del año y edad. Se han calculado los estadísticos de heterogeneidad y el posible sesgo entre publicaciones. Para la fertilidad, el RR medio fue 1,29, lo que significa que la melatonina incrementó de manera significativa las posibilidades de parto un 29%. Para la prolificidad, la D global fue 0,08 (d = 0,9089), es decir, los grupos tratados incrementaron su prolificidad 0,08 corderos/parto. El tratamiento con melatonina aumentó de manera significativa la fecundidad, con 0,25 corderos extra producidos/oveja tratada (d = 6,3188). En todos los casos, la heterogeneidad y el sesgo calculados fueron significativos (p < 0,001). En conclusión, el metaanálisis realizado ha revelado un efecto significativo de la melatonina en España sobre la posibilidad de que una oveja quede gestante, además de elevar el número de corderos nacidos por parto, lo que al final incrementa el número de corderos nacidos por oveja tratada. Esto no ha hecho sino confirmar lo revisado previamente en la literatura de manera narrativa, mediante una herramienta estadística, que sintetiza y estima de manera más precisa el efecto de esta hormona

A preliminary study of the effects of organic farming on oocyte quality in ewe lambs

This study tested whether feeding Rasa Aragonesa ewes certified organic feed, from 15 days before mating until lamb weaning, improved oocyte quality and in vitro maturation (IVM) and fertilization (IVF) performances of the offspring. In a second experiment, ovaries from ewe lambs that were bred on an organic farm and were of the same breed were compared with those from conventionally bred animals. The number (± standard error of the mean) of healthy oocytes per ewe lamb did not differ significantly between organic (12.2 ± 3.3) and conventionally (13.6 ± 4.0) fed ewes. Ovaries from ewe lambs born on an organic farm had significantly (P < 0.0001) more healthy oocytes per ewe lamb (39.6 ± 5.2) than did those born on a conventional farm (25.0 ± 4.2), and higher IVM (76.5% vs. 53.1%, P < 0.0001) and IVF (97.3 vs. 91%, P < 0.05) rates. In conclusion, this preliminary approach to the study of the effect of organic procedures on the sheep oocyte quality indicates that the total integration in the complete organic system improved the oocyte quality of ewe lambs, although organic feeding alone was insufficient to improve quality

Effects of weather and other factors on milk production in the Churra dairy sheep breed

The objective of this study was to investigate the influence of meteorological and other factors on the quality and quantity of milk of the Spanish Churra sheep breed, based on an analysis of 359, 808 milk controls from 9, 904 ewes on 15 farms in 8 years. Daily milk yield (DMY), fat, protein, and lactose (%), and somatic cell count (SCC) data were obtained from monthly alternating milk controls. Mean, maximum, and minimum temperatures (T) (°C), mean relative humidity (RH) (%), wind speed (WS, m/s), mean solar radiation (SR, MJ/m2), and total rainfall (RF, mm) on the day before each milk control day were documented. Year, farm, number of lambing and stage of lactation, and all of the meteorological factors had a significant (P &lt; 0.0001) effect on DMY and milk quality. DMY and SCC differed among seasons (P &lt; 0.001), and maximum DMY and minimum SCC occurred in spring, and minimum DMY and maximum SCC occurred in autumn. Fat, protein, and lactose content differed significantly (P &lt; 0.001) among seasons, and fat and protein contents were highest in autumn. DMY was highest in the second lambing of the ewe and steadily declined in subsequent lambings. SCC increased significantly from the first to the 10th lambing of the ewe. DMY, SCC, and fat content differed significantly (P &lt; 0.001) among years. In conclusion, meteorological conditions had a significant effect on milk quality and production in Churra sheep conditions in a season-dependent manner such that factors such as temperature had the opposite effect on milk production in hot and cold seasons

Performance evaluation of two slow-medium growing chicken strains maintained under organic production system during different seasons

A total of 160 1-day-old medium-growing male chicks (Gallus gallus domesticus) were raised for 120 days in a certified organic farming system. A total of two strains were studied (Coloryield, CY; RedBro, RB). Overall, two weather periods were considered based on the outdoor temperature, being S1 colder than S2. In total, 40 chicks per strain were assigned to each period (n = 80). Chickens were fed ad libitum with the same organic feeds. In the first month, chickens were kept indoors and, from day 30, they had access to the pasture. Slaughter live weight (LW), average daily gains, (ADG), the feed conversion ratio (FCR), and mortality rates did not differ between the two strains. LW was (p < 0.05) higher in the S1 and a trend (p = 0.084) was observed for ADG, which was higher in S1. No differences were found for feed intake, FCR, and mortality rates between weather periods. There were no differences for coefficient of variation (CV) between the strains studied, nevertheless, CV for LW in S2 was increased. Differences in the productive performance between these strains raised in organic production systems were slight. However, chickens raised in S1 had a better performance. It would be preferable to raise chickens in these weather conditions whenever possible. © 2021 by the authors. Licensee MDPI, Basel, Switzerland

La colaboración empresa-universidad en el ámbito de las razas ovinas autóctonas españolas: el ejemplo de Melovine

Se describe la colaboración establecida desde los años 90 hasta la actualidad entre un laboratorio veterinario (CEVA Salud Animal) y una universidad española (Universidad de Zaragoza), con la hormona pineal melatonina como eje. Los objetivos fundamentales han sido la descripción de los mecanismos básicos de actuación de esta hormona sobre la estacionalidad reproductiva de la especie ovina y la realización de pruebas de campo en ganaderías comerciales españolas, en un buen número de razas autóctonas, con el fin de difundir los resultados obtenidos en condiciones reales de explotación. Este hecho ha involucrado a todos los eslabones del sector ovino español, desde el laboratorio, el ganadero, la cooperativa, el veterinario, las asociaciones de defensa sanitaria, las administraciones públicas, las asociaciones de razas, coordinados todos ellos por un departamento universitario. Se ha trabajado con las razas autóctonas Castellana, Churra, Latxa, Manchega, Merina, Ojalada, Ojinegra, Rasa Aragonesa, Ripollesa y Segureña, además de otras como la Assaf y Lacaune. Se han descrito protocolos de uso de los implantes de melatonina en ovejas adultas, corderas y moruecos, en distintos momentos fisiológicos y sistemas de explotación. Todos ellos han sido difundidos al sector ovino español a través de publicaciones científicas y técnicas y a través de congresos, ponencias y cursos destinados a veterinarios y ganaderos

Highly precocious activation of reproductive function in autumn-born goats (Capra hircus) by exposure to sexually active bucks

Goats are seasonal breeders with the main cue controlling the timing of breeding season being photoperiod. Hence, the season of birth impacts puberty onset: spring-born goats reach puberty in autumn, at 7 mo of age, whereas autumn-born goats reach puberty at 1 yr during the next reproductive season. The aim of this study was to determine whether exposure of autumn-born young females to sexually active males could counteract the delay in puberty onset observed in autumn-born goats. Females exposed to sexually active males (n = 8) reached puberty earlier than isolated females (n = 8), with exposed females ovulating at a mean age of 3.5 mo. To our knowledge, such precocious puberty onset obtained through social stimulation has never been described in the literature. Moreover, those exposed females exhibited estrus behavior for most ovulations. Our results indicate that in goats born out of season, exposure to sexually active bucks is a really efficient approach to induce early puberty, suggesting that social interactions could have a crucial impact on the regulation of pubertal transition

Efecto de los implantes de melatonina y la presencia de compan~eros sobre los rendimientos de los moruecos durante la monta

Para evaluar el efecto de los implantes de melatonina sobre la capacidad de monta del morueco en pri- mavera, tanto en cubriciones en grupo como individuales, a inicios de febrero 6 machos recibieron tres implantes (M), mientras que otros 6 permanecieron como control (C). A finales de marzo 60 ovejas sin- cronizadas en celo se dividieron en 3 apartados (n = 20), introducie´ndose 4 machos en cada grupo (2M+2C). Durante 6 horas se realizo´ un test de monta, registra´ndose el nu´mero de montas y servicios y el intervalo entre servicios. Cuatro di´as ma´s tarde, 60 ovejas sincronizadas se dividieron en 12 apar- tados (n = 5), introduciendo un macho en cada grupo para realizar un test individual. Los machos tra- tados presentaron una mayor actividad sexual que los control (C: 24,5 ± 3,0; M: 25,9 ± 2,3 montas+ser- vicios; P < 0,05) y un menor intervalo entre servicios (C: 36,6 ± 6,6; M: 27,6 ± 2,1 min; P < 0,05). En grupo los machos fueron capaces de montar y servir ma´s veces que de forma individual (Grupo: 27,8 ± 3,1; In- dividual: 22,6 ± 1,8; P < 0,05). En conclusio´n, el tratamiento de los moruecos con implantes de melato- nina en primavera dio lugar a un aumento del nu´mero y la frecuencia de montas y servicios. Adema´s, se observo´ una mayor actividad sexual cuando los machos se encontraban en grupo que en solitario, independientemente del tratamiento

Daily rhythms of body temperature around lambing in sheep measured non-invasively

Fifteen ewes had data-loggers affixed under the tail, programmed to record temperature (T) every 5 min, storing up to 72 h of data. Ewes were monitored to identify time of lambing (time 0). Lambing period lasted 5 d; thereafter seven ewes which yielded data for 24 h before and after lambing were selected. Mean T (±S.E.M.) was 39.03±0.02°C. Mean T in the 24 h preceding lambing (38.68±0.02°C) was lower than it was in the 24 h following parturition (39.38±0.03°C) (P< 0.0001). T was lower in the 12 h preceding lamb birth (38.56±0.10°C) than it was in the previous 12 h (-24 to -12, 38.76±0.02°C) (P<0.0001); thereafter, T was lowest precisely at parturition (mean T = 38.18±0.03°C) and increases rapidly and peaked (mean T = 39.70±0.04°C) 2 h after lambing. In the 12 h following delivery (39.28±0.02°C), T increased, especially in the window +12 to +24 h (39.51±0.03°C). In conclusion, T of ewes changed around parturition, with a reduction 12 h before lambing, followed by a rapid increase in the hours following parturition. The data-loggers used proved a high degree of sensitivity to detect physiological T changes, which confirmed that they are appropriate for use in sheep studies