Nutritional parameters and productive performance of grazing sheep using castor bean cake as supplement or fertilizer.

The objective was to evaluate the effect of detoxified castor bean replacing soybean meal in the concentrate diet or as nitrogen organic fertilizer replacing urea on intake and nutrient digestibility, blood parameters and productive performance of sheep finished on irrigated Tamani grass pasture under continuous stocking and variable stocking rate. The treatments were two concentrate diets: standard (ground corn and soybean meal) and alternative diet (ground corn and detoxified castor bean cake), and two nitrogen fertilizers: chemical (urea) and organic (fresh castor bean cake). The randomized complete block design was used in a 2 × 2 factorial arrangement with four replications (500 m² paddocks). Four sheep (2 castrated males and 2 females) were distributed in each experimental unit, totaling 64 animals with an average initial weight of 19.42 ± 3.6 kg. No effects (P > 0.05) were observed on the variables inherent to the evaluation of the pasture. The average stocking rate (SR) among treatments was 85.50 sheep/ha, equivalent to 9.87 Animal Units (AU)/ha. The alternative diet presented lower dry matter digestibility (62.71%), with no negative effects on nutrient intake and kidney parameters. Animals fed the standard and alternative diet showed average daily gain of 103.75 and 86.76 g/day, respectively. A finishing period of up to 100 days is recommended for sheep selected for production systems in semi-arid regions managed intensively on pasture. Detoxified castor bean cake did not alter nutrient intake, liver and kidney parameters of the sheep and can be used in pasture-based sheep farming.

Castor bean cake for the control of parasites in pasture-finished sheep.

The purpose of this study was to evaluate castor bean cake as alternative input in the control of gastrointestinal parasites in sheep raised on irrigated pasture under continuous stocking. The treatments consisted of sheep supplemented with standard diet and pasture fertilized with urea; sheep supplemented with alternative diet and pasture fertilized with urea; sheep supplemented with standard diet and pasture fertilized with in natura castor bean cake; and sheep supplemented with alternative diet and pasture fertilized with in natura castor bean cake. A randomized complete block design (CBD) was used, with 16 replications (sheep), with repeated measures over time, the plots being the treatments, and the subplots the collection times. Infective nematode larvae in the pasture (L3.g DM-1), number of eggs per gram of feces (EPG), globular volume (GV), and total plasma protein (TPP) were evaluated. For adult gastrointestinal parasite counts, CBD was also used with six replications. Except for FAMACHA© grade, all variables had effect (P < 0.01) of the time factor. The average number of L3.g DM-1 and EPG were 126 and 841, respectively, with no effect (P > 0.05) of the treatment factor. The values observed for GV and TPP were higher than 25.9% and 6.4 g·dL-1, respectively, which were considered normal. As organic fertilizer, the fractionated application of in natura castor bean cake does not reduce the contamination of pastures by nematode larvae. The evaluated feeds improve the resilience of the sheep to infection by gastrointestinal parasites. The treatments using castor bean cake reduced the adult parasites present in the abomasum of sheep.