Developing a continuous adjustment factor for dry matter intake of gestating and lactating ewes

Intake is a multifactorial process that is influenced by animal type, environmental factors, and diet characteristics. Sheep, especially, have specific eating habits, with a greater selection of ingested feed compared to cattle. Thus, predictive equations for dry matter intake (DMI) must constantly be reviewed. The objective of this study was to combine different adjustment factors to develop one continuous adjustment factor for predicting the DMI of pregnant, dry, and lactating ewes. The equations evaluated for non-lactation ewes accounts for metabolic body weight and weight gain, and the equation for lactating ewes includes milk production and its fat content. The database used in this study was pooled from hair sheep ewes, two to four years old, with controlled feeding, during the pregnancy and lactating physiological phases. For the overall predictions (gestating and lactating ewes), the adjusted DMI prediction had greater accuracy but lower precision than the unadjusted DMI prediction. However, adjusting DMI increased the adequacy of the prediction as the mean square error of prediction difference (ΔMSEP) decreased (p = 0.0328). Similarly, for gestating ewes, the adjusted predicted DMI had a lower ΔMSEP than the unadjusted predicted DMI (p < 0.001). For lactating ewes, no difference was detected between the adjusted and unadjusted predicted DMI based on the ΔMSEP statistics (p = 0.3672), but the assumption that peak milk was 28 days (default) worsened the predictability of the adjusted predicted DMI as it had lower precision and accuracy. Adjustments for predicted DMI of dry and lactating ewes are necessary to increase adequacy and precision

Efeito da nutrição da ovelha e do cordeiro sobre o perfil de ácidos graxos do músculo Triceps brachii de cordeiros

O experimento foi realizado com o objetivo de avaliar o efeito da suplementação da ovelha 30 dias antes do parto, da idade à desmama (45 ou 60 dias) dos cordeiros e do sistema de terminação (em confinamento dieta total ou feno) ou a pasto sobre o perfil de ácidos graxos do músculo Triceps brachii de cordeiros machos não-castrados. O animais foram abatidos com 30 kg de peso corporal ou aos 150 dias de idade. Os cordeiros terminados em confinamento alimentados com feno foram abatidos pela idade e os demais pelo peso corporal. Os teores dos ácidos graxos C15:0, C16:0, C17:0, C16:1, C18:1 e C18:3 no músculo diferiram entre os sistemas de terminação dos cordeiros. O músculo dos cordeiros alimentados com dieta completa apresentou maiores valores de C16:0, C16:1 e C18:1, enquanto o músculo daqueles alimentados com feno e em pastagem apresentou maiores teores de C18:3. A dieta alterou o perfil de ácidos graxos no músculo dos cordeiros. A suplementação das ovelhas 30 dias antes do parto e a idade a desmama não afetaram o perfil de ácidos graxos.The objective of this work was to evaluate the supplementation of ewes 30 days before lambing, of the weaning age (45 or 60 days) of lambs and of the finishing system (on confinement - full diet or hay) or in grass on the profile of Tríceps brachii muscle fatty acid of no castrated male lambs. The animals were slaughter with 30 kg body weight or at 150 days-old. The lambs finished on confinement fed were slaughtered by age and the others by body weight. The content of fatty acids C15:0, C16:0, C17:0, C16:1, C18:1 and C18:3 were different among the lambs finishing systems. The muscle of lambs fed full diet shown highest values of C16:0, C16:1 and C18:1, while the muscle those fed hay or grass shown highest values of C18:3. The diet affected the fatty acid profile of muscle of lambs. The ewes supplementation 30 days before lambing and the weaning age did not affect the fatty acid profile

Influência da suplementação no pré-parto e da idade de desmama sobre o desempenho de cordeiros terminados em confinamento

Objetivou-se avaliar o efeito da suplementação no pré-parto e da idade à desmama sobre o desempenho de cordeiros terminados em confinamento. Foram utilizadas 44 matrizes mestiças Ile de France × Bergamácia acasaladas com cordeiro Ile de France mantidas em pastagem de Panicum maximum cv. Tanzânia, em sistema de pastejo rotacionado, até 30 dias antes do parto, quando foram separadas em dois grupos. No pré-parto, apenas o primeiro grupo (SUPL) recebeu suplementação (1% peso vivo) com dieta balanceada. Após o parto, ambos os grupos, com (SUPL) e sem suplementação (NS), receberam suplementação. Por sorteio, metade dos cordeiros de cada grupo foi desmamada aos 45 dias e a outra metade, aos 60 dias de idade. Após a desmama, os cordeiros foram mantidos em confinamento com dieta balanceada e abatidos aos 30 kg de PV, após jejum de sólidos de 16 horas. O peso e a condição corporal ao parto das ovelhas diferiram entre os grupos, o que não ocorreu ao desmame. Os peso ao nascimento e ao desmame, o ganho de peso do nascimento ao desmame e do desmame ao abate, o período em confinamento e a idade ao abate não diferiram entre os cordeiros. O peso ao desmame e o ganho de peso do desmame ao abate foram influenciados pela idade à desmama (os cordeiros apresentaram 0,20 kg aos 45 dias e 0,15 kg aos 60 dias de idade). A suplementação proporcionou melhor condição corporal às ovelhas e a desmama aos 45 dias promoveu melhor desempenho aos cordeiros.The objective of this trial was to evaluate the effect of ewe pre-partum supplementation and weaning age on performance of lambs. Forth-four Ile de France x Bergamasca ewes that were mated with Ile de France rams were used in this trial. Animals were maintained in a rotational grazing system of Panicum maximum (cv. Tanzânia) pasture until 30 days before parturition. Ewes were then divided in two groups: supplemented (SUPL) and not-supplemented (NS); animals on the SUPL group were supplemented (1% of body weight [BW]) with a balanced diet according to NRC (1985) requirements. After parturition, both groups were supplemented. Half of lambs from the SUPL and NS groups were weaned at 45 days of age and the other half at 60 days of age. After weaning lambs were feedlot fed with a diet balanced according to NRC (1985) model. Lambs were slaughtered when they reached 30 kg of BW after 16 hours of solids fasting. Both BW and body condition score of ewes at parturition differed between SUPL and NS groups while the same was not observed at weaning. Birth weight, weaning weight, weight gain from birth to weaning and from weaning to slaughter, days in feedlot, and slaughter age all were not different in lambs born from ewes of the SUPL or NS groups. However, significant differences were observed for weaning weight and weight gain from weaning to slaughter between groups of animals weaned at 45 or 60 days of age.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Economic performance of highenergy diets and supplementation with chromium propionate or calcium salts of palm oil in ewes’ production

The experiment aimed to analyze the economic viability of using highenergy diets and the supplementation of chromium propionate or calcium salts of palm oil in the diet of ewes from the late gestation until the end of lactation. Seventy-two ewes of Santa Ines × Dorper crossbreeds were allocated to five treatments: CTL (n = 14) with 100% of NRC recommendation for metabolizable energy per kg dry matter intake (ME/kg DMI), LOW (n = 14) with 90% ME/kg DMI, HIGH (n = 15) with 110% ME/kg DMI, Cr (n = 15) HIGH diet plus chromium propionate, and FAT (n = 14) HIGH diet plus calcium salts of palm oil. Based on the performance data, a short-term analysis was performed for a module of 1000 ewes, evaluating costs, revenues, and profitability, and long-term analysis was performed by an additional cash flow of 120 months. The CTL and FAT treatments were not viable due to higher costs and lower revenues, and they also had a negative net present value (NPV) and internal rate of return (IRR). The LOW treatment, despite lower costs and positive profitability, had a negative NPV (-$872.90) and IRR (1.85$64,894.11 and 104,902.05, respectively) and a higher IRR (9.03% and 13.65%, respectively) than the discount rate. The use of high-energy diets, with added chromium propionate, promoted better performance and, consequently, better economic retur

Influence of feeding regime and finishing system on lamb muscle fiber and meat quality

Avaliou-se a influência dos níveis nutricionais da ovelha antes do parto, da idade à desmama e do sistema de terminação sobre as fibras musculares e a qualidade da carne dos cordeiros. Utilizaram-se matrizes mestiças Ile de France × Bergamacia criadas a pasto. As ovelhas foram divididas em dois grupos: um com suplementação alimentar 30 dias antes do parto e outro sem suplementação. Os animais (ovelha e cordeiros) foram subdivididos de acordo com a idade à desmama (45 ou 60 dias de idade) e os cordeiros desmamados foram submetidos a três sistemas de terminação: confinamento com dieta completa; confinamento somente com feno; e confinamento somente no pasto. O abate dos cordeiros foi realizado aos 30 kg de peso vivo ou aos 150 dias de idade. As características de carcaça analisadas foram morfofisiologia da fibra do músculo longissimus dorsi, fragmentação miofibrilar pós-morte (maturados nos dias 0, 3 e 7 pos mortem) e redução do pH e da temperatura da carne pós-abate. Não houve efeito da suplementação às ovelhas ou da idade à desmama sobre nenhuma das características avaliadas. A composição em fibras de contração lenta e oxidativa, contração rápida e oxidativa ou contração rápida e glicolítica não foi alterada pelos fatores em estudo, mas a área transversal das fibras foi menor nos cordeiros terminados com feno, assim como os valores de pH, temperatura e as medidas dos fragmentos de miofibrila. Com o aumento do tempo de maturação de 0 para 3 e 7 dias post mortem, houve redução do comprimento dos fragmentos de miofibrilas. O sistema de terminação de cordeiros em confinamento somente com feno interfere mais intensamente na qualidade da carne que o sistema de terminação a pasto ou em confinamento com dieta completa.The study verified the influence of different nutritional levels of the dams, before parturition, the weaning age of the lambs and the finishing system on lamb muscle fiber morphology and meat quality. Ile-de-France × Bergamacia crossbred dams grazing on natural grassland were divided into two groups: 1) nutritional supplement 30 days before the parturition (SUPL), and 2) no nutritional supplement (NS). These groups were further subdivided by weaning age of the lambs, which corresponded to either 45 or 60 days. The weaned lambs from each of the previous groups were also divided into different finishing systems: confined and fed a complete diet (CD), confined and fed hay (H) and kept on grassland (P). The lambs were slaughtered at 30 kg live weight (CD and P), or at 150 days of age (H). The carcasses were cooled at 4ºC/24h. The analyzed variables were: longissimus dorsi muscle fiber morphophysiology, post mortem myofibrillar fragmentation (at 0, 3 and 7 days post mortem), meat pH and temperature. There was no effect of supplementation of dams or weaning age of the lambs for the evaluated variables. The frequency of slow-oxidative (SO), fast-oxidative-glycolytic (FOG) and fast-glycolytic (FG) muscle fiber types was not altered by the treatments, but the fiber cross-sectional area was smaller for the lambs finished only on hay, and the meat pH values and temperature were lower and the myofibrill fragment dimensions were smaller. As time maturation increased from 0 to 3 and 7 days post mortem, there was a decrease in the length of the myofibrill fragments. The diet of the lambs which were maintained confined and fed only with hay was nutritionally inferior when compared with all the others, and this changed the quality of the meat compared to the finishing systems on grassland or confined and fed complete diet