Effects of feeding mesquite pod meal (Prosopis juliflora (Swartz) DC) for horses

Sixteen mares of Mangalarga Marchador breed, averaging from 3.5 to 18.4 years old and 394.8 kg, were assigned to a randomized blocks (mares age) design, with four replicates by treatment, to evaluate the effects of replacing corncob meal (CCM) with mesquite pod meal (MPM) on nutrient intake. In the digestion trial, the total feces collection method was used and the coefficients of apparent digestibility of dry matter (CDDM), organic matter (CDOM), crude protein (CDCP), acid detergent fiber (CDADF), neutral detergent fiber (CDNDF), hemicellulose (CDHCEL) and gross energy (CDGE) were estimated. Diets were formulated to be isonitrogenous and isoenergetic, all containing coastcross hay and concentrate (60:40 ratio). The treatments consisted of increasing replacement levels of CCM with MPM, as follows: 0, 33, 66 and 100%. No effects of mare age on the variables were detected. No significant effect of increasing MPM levels on dry matter intake, with mean values of 1.8% body weight (BW), 7.02 kg DM/day, 79.84 g DM/kg BW0.75, was observed. CDDM, CDOM, CDCP and CDHCEL did not differ among diets and showed the respective mean values of 49.15, 50.18, 56.89, and 35.43%. Linear decreasing effect on CDNDF and quadratic effect on CDADF and CDGE were observed as the dietary levels of MPM increased. According to the regression equations, maximum point of CDADF could be obtained by replacing 22.3% MPM and maximum values of CDNDF and CDGE in the diets without MPM. It was concluded that, despite of decrease on dietary fiber digestibility, mesquite pod meal can be used in horses diets.