Effect of replacing wheat bran with spineless cactus plus urea in sugarcane-based diets for sheep

In times of drought, the availability of feed is reduced, and the use of concentrate ingredients, such as wheat bran, becomes costly for animal production. Thus, the use of spineless cactus emerges as a potential solution to the shortage of feed and water during prolonged drought periods. The objective of this study was to evaluate the effects of replacing wheat bran with spineless cactus plus urea (0%, 25%, 50%, 75%, and 100%) in sugarcane-based diets for sheep on nutrient intake, feeding behaviour, nitrogen balance and microbial protein synthesis. Five male Santa Ines sheep with average initial bodyweight of 34.0 ± 3.6 kg were used in a 5 × 5 Latin square. The maximum intakes of dry matter (DM) (1414 g/day), organic matter (OM) (1281 g/day), crude protein (CP) (204 g/day), neutral detergent fibre corrected for ash and protein (NDFap) (425 g/day), and total digestible nutrients (TDN) (890 g/day) were estimated with replacement levels of 80.2%, 75.3%, 88.6%, 50.5%, and 79.3% respectively. Feeding behaviour was not altered by replacing wheat bran with spineless cactus plus urea. Nitrogen retention increased by 0.10 g/day, while plasmatic urea nitrogen increased by 0.20 mg/day for every 1% level of replacement. The maximum production of microbial nitrogen (15.9 g/day) and microbial protein synthesis (99.4 g/day) were estimated with replacement levels of 45.8 and 45.7%, respectively. It is concluded that up to 80% wheat bran could be replaced with spineless cactus plus urea in sugarcane-based diets for sheep.Keywords: Alternative feed, drought, feeding behaviour, intake, microbial protei

Orelha de Elefante Mexicana (Opuntia stricta [Haw.] Haw.) spineless cactus as an option in crossbred dairy cattle diet

new genotype of spineless cactus is being used in the diets of dairy cattle that are raised in semi-arid regions. However, little is known about its nutritional value. This study aimed to evaluate the effects of replacing Miúda (Nopalea cochenillifera Salm Dyck) with Orelha de Elefante Mexicana (Opuntia stricta [Haw.] Haw.) spineless cactus, on nutrient intake and digestibility, milk yield and composition, feeding behaviour, microbial protein synthesis, nitrogen balance, and ruminal and blood parameters of dairy cows. Ten Girolando cows, 500 ± 51.6 kg bodyweight, were distributed in a double Latin square design 5 x 5. The treatments consisted of replacement levels of Miúda (MIU) by Orelha de Elefante Mexicana (OEM) at 0, 25, 50, 75, and 100%. The intake and digestibility of dry matter (DM) (14.38–12.95 kg d-1, 716.3–658.9 g d-1), organic matter (OM) (13.01–11.43 kg d-1, 747.8–704.8 g d-1), crude protein (CP) (2.02–1.61 kg d-1, 863.8–845.2 g d-1) and total digestible nutrients (TDN) (9.38–7.92 kg d-1) decreased linearly with the increase in replacement. Despite the decrease in intake and digestibility, the supply of nutrients was sufficient to maintain a milk yield of 12.5 kg d-1. The average daily weight gain decreased linearly with the increase in replacement, while protein microbial efficiency (g microbial CP kg-1 TDN intake; 91.24 to 127.44 g kg-1) increased linearly. Thus, OEM could replace 100% MIU in diets with 48% of spineless cactus, for crossbred lactating cows with 12.5 kg d-1 milk yield. Therefore, OEM is a viable new option for producing milk in smallholder livestock systems in semi-arid regions.Keywords: Alternative forage, milk yield, ruminal parameter, semi-arid, smallholder livestock syste