Se estudió el efecto del tipo de parto (corderos únicos: CU vs. corderos mellizos: CM), de la suplementación (0,8 % ¯-en base seca-¯ del peso vivo) a corderos al pie de sus madres (con acceso diferencial al suplemento: CADS vs. sin acceso diferencial al suplemento: SADS) y la asignación de forraje (baja: BAF= 5 % vs. alta: AAF= 10 %), sobre el desempeño de 24 ovejas Merino Australiano (12 de parto simple y 12 de parto doble) y de sus 36 corderos Dorper x Merino Australiano. Las ovejas con CU no mostraron las pérdidas de peso y estado corporal de sus contemporáneas con CM (0,029 vs. - 0,007 kg/día y 2,7 vs. 2,5, respectivamente): aquellas que pastoreaban en AAF mostraron ganancias de peso, en tanto que las que pastorearon BAF perdieron peso (0,031 vs. - 0,017 kg/día, respectivamente). Independientemente del tipo de parto, la respuesta a la suplementación de los corderos sólo se manifestó en aquellos que pastoreaban al pie de sus madres en BAF (0,175 vs. 0,132 kg/día; CADS y SADS p£0,05, respectivamente).

The effect of birth type (single: S or twins: T), supplementation (0.8 % of body weight) for weaned lambs (with creep feeding: CCF or without creep feeding: SCF) and the forage allowance (low: LFA = 5 % or high: HFA = 10 % of body weight) was evaluated on the performance of 24 Australian Merino sheep (12 from single birth and 12 from twin birth), and their 36 Dorper x Australian Merino lambs. The S sheep did not show the same weight loss and body condition of their T contemporaries (0.029 or -0.007 kg/day and 2.7 or 2.5, respectively): those which were in HFA gained weight, while those in LFA lost weight (0.031 and -0.017 kg/day, respectively). Regardless of birth type, the response to supplementation of lambs was evident only in weaned lambs in LFA (0.175 and 0.132 kg/day; CCF and SCF p£0.05, respectively).

El objetivo del trabajo fue evaluar el efecto del uso de diferentes dietas con alto contenido de grano sobre el comportamiento ingestivo de corderos en confinamiento. Se utilizaron 32 corderos machos castrados de la raza Texel destetados con aproximadamente 50 días de edad. Los tratamientos fueron cuatro dietas en base a diferentes granos de cereales no procesados: maíz, avena blanca, avena negra y arroz con cáscara. Los corderos alimentados en base a grano de maíz mostraron menos tiempo a las actividades de rumia y masticación, dedicando más tiempo al ocio. Además de eso, estos corderos presentaron mayor consumo de materia seca (0,885 kg/día), menor eficiencia de alimentación en términos de FDN y mejor eficiencia de rumia de la MS (226,05 g MS/h) y de la FDN (33,61 g FDN/h) frente a los corderos de los otros tres tratamientos. El comportamiento ingestivo de corderos en confi namiento con el uso de dietas con alto contenido de grano basado en maíz, avena blanca, avena negra y arroz con cáscara se somete a cambios causados principalmente por el consumo voluntario de alimento y la proporción de FDN presente en las dietas experimentales.

The aim of this study was to evaluate the effect of using different high-grain diets on the feeding behavior of lambs finished in feedlot. 32 male castrated Texel breed and weaned at approximately 50 days of age lambs were used. The treatments were four diets based on different types of cereal grains, not processed, as follows: corn grain, white oat grain, black oat grain or grain of rice in the husk. Lambs fed diets with high corn grain spent less time ruminating and total chewing activity and remained longer time in idleness. Moreover, had higher dry matter intake, lower feeding efficiency in relation to NDF and better rumination efficiency of DM and NDF compared with lambs from the other three treatments. The feeding behavior of feedlot finished lambs with the use of high-grain diets based on corn, white oat, black oat or rice in the hulls suffer changes caused mainly by the voluntary feed intake and the proportion of NDF present in the experimental diets.

O objetivo desse trabalho foi avaliar o efeito do uso de diferentes dietas de alto grão sobre o comportamento ingestivo de cordeiros terminados em confinamento. Foram utilizados 32 cordeiros machos, castrados, da raça Texel e desmamados com aproximadamente 50 dias de idade. Os tratamentos foram quatro dietas baseadas em diferentes tipos de grãos de cereais, não processados, sendo: grão de milho, grão de aveia branca, grão de aveia preta ou grão de arroz com casca. Os cordeiros alimentados com dietas de alto grão de milho despenderam menor tempo em atividades de ruminação e de mastigação total e permaneceram maior tempo em ócio. Além disso, apresentaram maior consumo de matéria seca, menor eficiência de alimentação em relação à FDN e uma melhor eficiência de ruminação da MS e da FDN quando comparados com cordeiros dos outros três tratamentos. O comportamento ingestivo de cordeiros terminados em confinamento com o uso de dietas de alto grão a base de milho, aveia branca, aveia preta ou arroz com casca sofre alterações provocadas principalmente pelo consumo voluntário de alimento e pela proporção de FDN presente nas dietas experimentais.

Mucha literatura trata sobre factores que afectan el pH de la carne; generalmente estudia efectos principales o a lo sumo interacciones entre algunos de ellos. En este trabajo se buscó identificar aquellos factores con mayor incidencia sobre el pH de la carne medido a las 36 h post mórtem e interacciones complejas entre ellos. Se utilizó una base de datos con 1800 registros completos de animales sacrificados en siete frigoríficos que en conjunto representaban el 50% de la faena del Uruguay. Con factores medidos en los diferentes segmentos de la cadena cárnica se ajustó un árbol de decisiones que puso de manifiesto doce nodos terminales. Se observó que aunque el frigorífico no realizara estimulación eléctrica, si tenía buenas condiciones de higiene en los corrales de espera y a su vez la distancia entre éstos y el cajón de noqueo era corta, la incidencia de pH³5,8 en la carne era baja. La falta de higiene en los corrales afectó más a animales de razas británicas puras (Hereford y Aberdeen Angus) que a sus contemporáneos cruzas. La falta de acceso al agua previo al embarque incidió más en novillos que en vacas. Un inadecuado método de arreo, mal estado del desembarcadero y viajes de mayor duración generaron problemas de pH³5,8 en carne. Características del frigorífico, propias de los animales, de manejo durante el embarque y desembarque, así como aquellas asociadas al transporte tuvieron efectos que, interactuando, afectaron el pH de la carne vacuna medido a las 36 h post mórtem

Most bibliography quotes factors related to pH effect on beef meat; generally principal effects or some interactions between them. This research work tried to identify those factors with main effects on beef meat pH, measured at 36 h post mortem and all complex interactions between them. A data base of 1800 complete registers from animals, out seven slaughter plants which altogether explain 50% of the slaughter in Uruguay. With factors measured on the different stages of the process, a decision tree was adjusted, which showed 12 terminal nodes. It was observed that if the slaughter plant did not use electrical stimulation, if the hygiene conditions were good in the holding pens, and the distance between them and the stunning box was short, the incidence of pH³5.8 in meat was low. The lack of hygiene in pens affected more pure British breeds (Hereford and Aberdeen Angus), than their cross breeds contemporaries. Lack of acces to water before the trip had affected more steers than cows. Improper method of herding, poor condition of the landing and longer journeys generated pH³5.8 in the meat. Plants features, animal’s own characteristics, handling during loading and unloading, as well as elements associated with transport had effects that, in interaction, affected the pH of beef meat measured at 36 h postmortem.

La incidencia de canales ovinas con agentes extraños es significativa en el Uruguay: cada dos canales, una está contaminada. Las condiciones de los camiones y la forma en que se comercializan los corderos agrava el problema. El objetivo de este trabajo fue estudiar en un diseño completamente aleatorizado con arreglo factorial de tratamientos el efecto de la posición en el camión: PC (nivel superior o inferior) y del sistema de lavado con agua fría a presión (no lava: NL, lava llegada: LL o pre-sacrificio: LPS) sobre la contaminación (aerobios totales, Enterobacteriacea y E. coli) de 80 corderos. La interacción PC x LL resultó significativa (p = 0,05) para aerobios totales (4,48; 3,97; 4,52 y 4,61 número de colonias log 10, para canales de corderos transportados arriba lavados y sin lavar ó abajo, lavados y sin lavar, respectivamente). Mientras que la interacción PC x LPS lo fue para Enterobacteriacea (2,76; 2,25; 2,53 y 2,53, número de colonias log 10, para corderos transportados arriba lavados y sin lavar o abajo, lavados y sin lavar, respectivamente; p = 0,04) y E. coli (324, 59, 110 y 253 número de colonias/cm² para corderos transportados arriba lavados y sin lavar o abajo, lavados y sin lavar, respectivamente; p = 0,0001). Los resultados muestran que el lavado sólo se justificaría cuando los corderos son transportados en el piso inferior, particularmente para E. coli, aunque sólo los corderos del piso superior y que no se lavaron mostraron conteos de microorganismos aceptables.

In Uruguay, the incidence of ovine carcasses contamination with extraneous is significant: every two carcasses, one is contaminated. Truck characteristics, type of sheep breeds and commercialization with wool contribute to increases the problem. The aim of this work was to study with complete random design with factorial treatments arrangement the effect of truck position (upper or lower level) and washing system with pressurized cold water (no washing: NW, arrival washing: AW or pre-slaughter washing: PSW) on contamination aerobic bacteria, Enterobacteriacea and E. coli) of 80 lambs. The interaction truck position x AW affected (p = 0.05) aerobic bacteria (4.48; 3.97; 4.52 and 4.61 log 10 colonies number in lambs transported in the upper level of the truck, washed and not washed, or transported in the lower level, washed or not washed, respectively). The interaction truck position x PSW affected (p = 0.04) Enterobacteriacea (2.76; 2.25; 2.53 and 2.53, log 10 colonies number, in lambs in the upper level, washed and not washed, or in the lower level, washed or not washed, respectively) and affected (p = 0.0001) E. coli (324; 59; 110 y 253 number of colonies/cm², in lambs in the upper level washed and not washed or in the lower level washed or not washed, respectively). The results suggest that washing lambs is justified only when lambs were transported in the inferior floor of the truck, particularly for E. coli decontamination. Only the lambs transported in upper floor and not washed showed adequate microorganism counts.

Na região de solos de Basalto (Salto, Uruguai: 32.5º de latitude sul e 58º de longitude oeste), estudou-se, em um delineamento em blocos casualizados com arranjo fatorial, o efeito de 3 manejos alimentares pos-desmame (MAPD: I : 1,2cm de altura da forragem disponível e 16 ovelhas/ha; II: 2,03cm de altura da forragem disponível e 5 ovelhas/ha; III: 2,5cm de altura da forragem disponível e 1 ovelha/ha) e 2 níveis de alimentacão no período de encarneiramento (NAE: campo natural: 883kg MS verde/ha, PB: 114g/kg MS e FDN: 781g/kg MS; pastagem artificial: 1270kg MS/ha, PB: 194g/kg MS e FDN: 598g/kg MS), no desempenho reprodutivo de 300 ovelhas Merino. O MAPD estendeu-se por 70 dias. O período de encarneiramento foi de 13/4-13/5/96 e os NAE foram aplicados por 30 dias, iniciando-se 15 dias antes do início do período de cobertura. O número de cordeiros nascidos/ovelha cobertas incrementou-se ao aumentar a taxa ovulatória devido ao fato de o maior número de óvulos liberados compensar a menor viabilidade destes. O número de cordeiros nascidos/ovelha coberta foi maior nas ovelhas provenientes do MAPD III (1,18, 1,11 e 0,96, MAPD III, II e I, respectivamente, P = 0,02) e naquelas que foram submetidas às pastagens artificiais durante o período de encarneiramento (1,13 e 1,03, pastagem artificial e natural, respectivamente, P = 0,10). Essas foram as que apresentaram uma tendência de valores superiores em taxa ovulatória.

In the uruguayan Basalt region, the reproductive performance of 300 Merino ewes and the effect of 3 post-weaning feeding managements (PWFM: I: 1.2 cm height of available forage and 16 ewes/ha; II: 2.03 cm height of available forage and 5 ewes/ha; III: 2.5cm height of available forage and 1 ewe/ha) as well as 2 feeding levels before and during the breeding season (FLM: native pastures: green DM/ha: 883kg, CP: 114g/kg DM, NDF: 781g/kg DM and improved pastures: DM /ha: 1270kg, CP: 194g/kg DM, NDF: 598g/kg DM) were studied with a factorial arrangement of treatments. The PWFM extended for 70 days, ewes were mated in the period from 13/4/96 to 13/5/96 and FLM were applied for 30 days, starting 15 days before beginning of breeding. There were not differences on the ovulation rate (P>0.05); however, the P values might indicate some effect of the treatments. The number of born lambs/ewe served increased with the ovulation rate because the higher number of ovulations balanced their less viability, individually considered. Actually, the number of born lambs/ewe served was higher with animals coming from PWFM III (1.18, 1.11 and 0.96, PWFM III, II and I, respectively; P = 0.02) and with the animals grazing on improved pastures at mating period (1.13 and 1.03, improved pastures and natural pastures, respectively; P = 0.10), were those which showed slight higher ovulation rate.