Production and slaughter performance of ostriches fed full-fat canola seed

Abstract

Full-fat canola seed (FFCS) is a locally produced alternative protein source that has potential for inclusion in the diet of ostriches. Chicks aged 84 days and weighing 24.7 ± 0.36 kg were fed five iso-nutritional diets with varying levels of FFCS. Birds were fed until slaughter at 309 days old (93.2 ± 1.82 kg). In each feeding phase, FFCS replaced soybean oilcake meal incrementally (0%, 25%, 50%, 75% and 100% of protein source). Dry matter intake (DMI) during the grower phase was lowest (1.52 kg/bird/day) for the 100%FFCS diet. Birds on the 100%FFCS also showed a 34% slower growth rate (average daily gain of 152.0 g/bird/day) compared to the other four diets (average growth rate of 230 g/bird/day) during the grower phase. The 0%FFCS (236.2 g/bird/day) and 50%FFCS (267.8 g/bird/day) diets resulted in a higher ADG. End weights during the grower phase for 0%FFCS, 25%FFCS, 50%FFCS and 75%FFCS (74.8, 72.2, 76.8, and 72.5 kg, respectively) did not differ significantly. The 100%FFCS resulted in a lower end weight (67.4 kg) for the growth phase, when compared to the 0%FFCS and 50%FFCS diets. For the overall trial period, the only differences were in ADG, with the 0%, 50% and 75%FFCS replacement diets showing the fastest growth. Fat pad weight was the only slaughter trait that revealed differences between diets, with 50%FFCS resulting in the heaviest fat pad weight. A maximum of 20.6% inclusion of FFCS should be used in diets in the grower phase, although in the other phases, FFCS could be included up to the maximum level evaluated (100% replacement of soybean oilcake meal) without detrimental effects on production parameters.Keywords: Average daily gain, Brassica napus, dressing percentage, dry matter intake, feed conversion ratio, glucosinolates, Struthio camelus

Kleiber ratios and growth curves of African Black and Red Neck ostrich breeds and their crossbreeds

“…Ostrich products are not restricted to meat. Thus, it is important to report that when examining the growth of birds, it is necessary to separate the growth of feathers from the growth of the rest of the body (Niemann et al, 2018). Feather proteins differ from body proteins, and the maturation rate is different for feathers and total body protein weight (Emmans & Fisher, 1986).…”

“…where Ut is the maturity degree (%), Yt is the weight (kg) of the ostrich at 90, 180, and 400 days, and A is the asymptotic weight. The Gompertz function was chosen because of its economy of parameters and ability to describe relative growth rate as a simple function of size (Ramos et al, 2013); it has been used in other studies to evaluate ostrich growth (Niemann, Brand, & Hoffman, 2018). In addition, the function offers the possibility of describing continuous growth, sigmoid forms, asymptotes, inflection points, and parameters with biological interpretations.…”