Abstract The aim was to evaluate the effect of replacing ground corn with spineless cactus from two species Orelha de Elefante Mexicana-OEM (Opuntia stricta Haw.) and Gigante (Opuntia ficus-indica Mill) in a total mixed ration for finishing lambs evaluating its effects on intake, ingestive behavior, performance, carcass traits, commercial cuts and physiochemical composition of the meat. Eighteen crossbred lambs with average body weight of 15.0 ± 2.32 kg were distributed in a completely randomized design with three treatments (OEM and Gigante spineless cactus and ground corn as control treatment) and six replications. Spineless cactus species replacing ground corn in lambs diets does not change the intake of dry matter (DMI), crude protein and neutral detergent fiber or time (min/d) of ingestion, rumination and idleness, or final body weight gain. Lambs fed with ground corn and "Gigante" cactus presented a higher total weigh gain (TWG) and average daily weight gain (ADG) when compared to OEM spineless specie. Ground corn diet promoted better hot and cold carcass yield in lambs receiving spineless cactus, regardless of species. Feed and total costs (kg/lamb) were higher for the ground corn diet. The replacement of ground corn with spineless cactus did not change moisture, protein, and ash meat contents, as well as water holding capacity, cooking loss, shear force, and a* color intensity. However, there was an effect for the meat lipid content, b* and L* color intensity and color index, where the species of cactus Gigante on ground corn presented the highest lipid content and yellowness (b*) intensity and lower L* color compared to OEM. Spineless cactus species Gigante can replace ground corn as a source of energy in diets for finishing lambs because it significantly improves the financial income for the producer without changing the ADG, DMI, ingestive behavior and yield of commercial cuts.

Resumo Objetivou-se avaliar o efeito da substituição do milho moído por duas espécies de palma forrageira, Orelha de Elefante Mexicana-OEM (Opuntia stricta Haw.) e espécie Gigante (Opuntia ficus-indica Mill) em uma ração completa para terminação de cordeiros avaliando seus efeitos sobre consumo, comportamento ingestivo, desempenho, características de carcaça, cortes comerciais e composição físico-química da carne. Foram utilizados dezoito cordeiros sem padrão racial definido com peso corporal médio de 15,0 ± 2,32 kg e foram distribuídos em delineamento inteiramente casualizado com três tratamentos (OEM e palma Gigante e grão de milho como controle) e seis repetições. As duas espécies de palma forrageira em substituição ao milho moído na dieta de cordeiros não modificaram o consumo de matéria seca (CMS) proteína bruta e fibra em detergente neutro nem o tempo (min/dia) de ingestão, ruminação e ócio ou ganho corporal final. Cordeiros alimentados com milho moído e palma Gigante apresentaram maior ganho de peso total (GPT) e médio diário (GMD) em relação à espécie OEM. A dieta com milho moído promoveu melhor rendimento de carcaça quente e fria comparando cordeiros recebendo palma forrageira, independente da espécie. Os custos com ração e total (kg/cordeiro) foram maiores para a dieta com milho moído. A substituição do milho moído pela palma forrageira não alterou os teores de umidade, proteína e cinzas da carne, bem como a capacidade de retenção de água, perda por cozimento, força de cisalhamento e intensidade de cor a*. No entanto, houve efeito para o teor de lipídios da carne, índice de intensidade de cor b* e L*, sendo que a espécie de palma Gigante e o milho grão moído apresentou o maior teor de lipídios e intensidade de amarelo (b*) e menor cor L* em relação ao OEM. A espécie palma forrageira Gigante pode substituir o milho moído como fonte de energia em dietas para cordeiros em terminação, pois melhora significativamente o rendimento financeiro do produtor sem alterar o GMD, CMS, comportamento ingestivo e rendimento dos cortes comerciais.

The objective was to evaluate the effect of salinity of irrigation water and different cutting ages on the biomass components of Echinochloa pyramidalis. Seedlings were planted in plastic pots (volume of 8 L) with sandy-textured Quartzarenic Neosol, under greenhouse conditions. The design was completely randomized in split plots with salinity levels (0.75, 2.0, 4.0, 6.0 and 8.0 dS m-1) in the main plot, and cutting ages (21, 28, 35, 42 and 49 days) in the subplots, with five replicates. After the standardization cut, the dry masses of total forage, dead forage, live forage, green leaf blade, green stem and ratios of live material/dead material and leaf/stem were determined. There was no interaction between the factors studied. Salinity decreased the dry masses of total forage, green leaf blade and green stem. Salinity had no effect on the dry masses of dead forage or ratios of live material/dead material and leaf/stem. Salinity changed the partitioning of dry matter, reducing the percentage of stems, and increasing the percentage of leaves in the dry mass of total forage. The advance in the cutting age caused increases in the dry masses of total forage, dead forage, live forage, green stem and green leaf blade. From the cutting age of 28 days, dead forage dry mass had a very sharp increase. The increase in stem dry mass rose from the 35th day. The extension of the cutting age promoted a decline in the live material/dead material and leaf/stem ratios. The cut of Echinochloa pyramidalis at 21 days, when it presents the best leaf/stem ratio is recommended.

This study was carried out to estimate efficiencies of the utilization of metabolizable energy for maintenance (k m) and weight gain (k g) and to evaluate the Small Ruminant Nutrition System (SRNS) model in predicting dry matter intake and average daily gain of growing Santa Ines sheep. Twenty-four non-castrated Santa Ines sheep, at 50 days of age and with average body weight of 13.00 ± 0.56 kg, respectively, were used. After a 10-day adaptation period, four animals were slaughtered to be used as reference for estimating initial empty body weight and body composition of the other animals. The remaining animals were distributed in a random block design, with the treatments consisting of diets containing different levels of metabolizable energy (2.08, 2.28, 2.47 and 2.69 Mcal/kg of DM), with five replicates. The metabolizable energy use efficiencies for maintenance and for weight gain were calculated from the relationship between the dietary net energy for maintenance and gain and ME concentration in the diets. Evaluation of the SRNS model was performed by adjustment of simple linear regression model between the predicted (independent variable) and observed (dependent variable) values. The estimated energy use efficiency for maintenance (k m) was 0.70; and for gain weight (kg) it showed to be inversely proportional to the increase of metabolizable energy concentration in the diet. The dry matter intake predicted by the SRNS model did not statistically differ from that observed, but the model overestimated the average daily gain by 5.18%. Those results can contribute to the construction of a database, which could be condensed into several others in a predictive model of performance and feed planning for sheep reared in Brazil.

This study evaluated intake and apparent digestibility of the nutrients in the diet of Morada Nova sheep that received diets containing increasing levels of juazeiro hay in substitution of Tifton 85 bermudagrass hay (0, 33, 67 and 100%). Sixteen non castrated male sheep, weighing an average of 26.75 kg, were used, placed in individual metabolic cages and distributed in a completely randomized block design with four treatments and four replications. Intakes of dry matter, organic matter, crude protein, ether extract, neutral detergent fiber, total carbohydrates, fibrous carbohydrates and non-fibrous carbohydrates and total digestible nutrients were not influenced by the addition of juazeiro hay to the diets, with mean values of 1,042.78 and 595.59 g/day of dry matter and neutral detergent fiber intake, respectively. Linear reduction was observed for digestibility of the dry matter, organic matter, neutral detergent fiber and fibrous carbohydrates. Quadratic reduction was observed for the acid detergent fiber digestibility coefficient. The digestibility coefficients of the crude protein, ether extract, total carbohydrates and fibrous carbohydrates were not significant. The nitrogen balance was not influenced and was positive for all the treatments. The inclusion of juazeiro hay did not influence nutrient intake or nitrogen balance, but reduced the digestibility coefficient of some diet components.

This study aimed at estimating the kinetic parameters of ruminal degradation of neutral detergent fiber from agroindustrial byproducts of cashew (pulp and cashew nut), passion fruit, melon, pineapple, West Indian cherry, grape, annatto and coconut through the gravimetric technique of nylon bag, and to evaluate the prediction equation of indigestible fraction of neutral detergent fiber suggested by the Cornell Net Carbohydrate and Protein System. Samples of feed crushed to 2 mm were placed in 7 × 14 cm nylon bags with porosity of 50 µm in a ratio of 20 g DM/cm² and incubated in duplicate in the rumen of a heifer at 0, 3, 6, 9, 12, 16, 24, 36, 48, 72, 96 and 144 hours. The incubation residues were analyzed for NDF content and evaluated by a non-linear logistic model. The evaluation process of predicting the indigestible fraction of NDF was carried out through adjustment of linear regression models between predicted and observed values. There was a wide variation in the degradation parameters of NDF among byproducts. The degradation rate of NDF ranged from 0.0267 h-1 to 0.0971 h-1 for grape and West Indian cherry, respectively. The potentially digestible fraction of NDF ranged from 4.17 to 90.67%, respectively, for melon and coconut byproducts. The CNCPS equation was sensitive to predict the indigestible fraction of neutral detergent fiber of the byproducts. However, due to the high value of the mean squared error of prediction, such estimates are very variable; hence the most suitable would be estimation by biological methods.