Parkia platycephala replacing ground corn in the diet of confined lambs: intake, digestibility, ingestive behaviour, rumen fermentation and carcass yield.

Abstract

This study aimed to evaluate the intake, digestibility, ingestive behaviour, productive performance, rumen fermentation and carcass yield of lambs fed diets with Parkia platycephala pods (PP) replacing ground corn. For this, twenty-eight castrated male lambs (18.34 ± 4.81 kg, 120 days of age), were distributed in randomised blocks with 4 treatments and 7 replicates. Four diets were formulated replacing ground corn with PP (0, 33, 66, and 100%) on a roughage: concentrate ratio of 30:70 on a dry matter basis. The feedlot period lasted for 60 days, and the animals were slaughtered consecutively. The replacing of ground corn with PP reduced the intakes of ether extract and metabolisable energy, digestibility of dry matter, organic matter, crude protein, ether extract, neutral detergent fibre, total digestible nutrients, isovalerate, and omental + mesenteric fat, while it increased the digestibility of non-fibrous carbohydrates, carcass finishing, and the yields of rumen, reticulum, and omasum (p < 0.05). A quadratic effect was observed for the time of chews per rumen bolus, number of rumination chews per day, number of rumination chews per bolus, and number of rumination chews per minute, propionate (p = 0.002), butyrate (p < 0.01) and total short chain fatty acids (SCFA) (p < 0.05) according to the increase in PP levels replacing ground corn in diets offered to lambs. The rumen pH was reduced and the NH₃-N increased according to the evaluation period (p < 0.05). The highest concentration of total SCFA was observed in the collection carried out at 09 h (p < 0.05). The use of up to 100% PP in diets offered to lambs is recommended as it provides nutrient intake, weight gain, and carcass yield similar to ground corn.