Further studies on the use of solar-dried blood meal as a feed ingredient for poultry

Abstract

Two studies, using broilers and laying hens, were conducted to further determine the nutritive value of solar-dried blood meal (SDBM). In experiment 1, diets containing 0, 30, 60 and 90 g SDBM kg* 1 were fed ad libitum to 240 two-week-old broiler chickens for a period of 6 weeks. The level of SDBM had no significant effect on feed intake, body weight gain, feed conversion efficiency, carcass yield, or mortality. In experiment 2, 144 brown egg layers of 26 weeks of age randomly allotted into four groups were fed diets containing 0, 15, 30 and 45 g SDBM kg"1 for 20 weeks. The inclusion of graded levels of SDBM in layer diets positively influenced feed intake (r=0.95; PO.05), body weight gain, egg weight, yolk colour, and Haugh unit score. Hen-day egg production and feed conversion efficiency were, however, unaffected. There were neither health-related problems nor deaths associated with the amount of SDBM in the diet. It is concluded that dietary SDBM up to 45g kg' 1 had a positive effect on layer performance and that in broiler diets, partial replacement of other protein sources (fish meal and copra cake) with SDBM is possible.

The rat as a model animal for the growing pig in determining ileal amino acid digestibility in soya and milk proteins

“…The endogenous amino acid flows were determined for both rats and pigs. Endogenous amino acid flows reported here were generally lower than those found previously in our laboratory (Moughan and Rutherfurd, 1990;Butts et al, 1991;Donkoh et al, 1994;Hendriks et al, 2002). This may have been because of the preponderance of smaller peptides (<2000 daltons) in the enzymatically hydrolysed casein used in the present study compared with that used in previous studies (Fig 1.…”

“…For cysteine, but for no other amino acid examined, both the highest difference and the overall average difference were of such magnitude to be considered of practical importance in nutrition. For all amino acids examined, except for cysteine and histidine, the overall average , and that used in previous studies (Moughan and Rutherfurd, 1990;Butts et al, 1991;Donkoh et al, 1994) (dashed line).…”

“…This may have been because of the preponderance of smaller peptides (<2000 daltons) in the enzymatically hydrolysed casein used in the present study compared with that used in previous studies (Fig 1. ) where peptides as large as 5000 Da were present (Moughan and Rutherfurd, 1990;Butts et al, 1991;Donkoh et al, 1994). There may be a relationship between the size of peptides present in the gut and the level of endogenous protein secretion.…”

“…In humans, the ileal digestibility of amino acids in foods can be determined directly using human ileostomates, but this approach is not straightforward and cannot be used for routine food evaluation. Consequently, model animals have been used and the growing pig appears to be a satisfactory model animal for determining protein digestion for the adult human (Moughan and Rowan, 1989;Donkoh et al, 1994;Rowan et al, 1994).…”

“…Pig ileal amino acid digestibility assays, however, are labour intensive and relatively expensive. The laboratory rat may be a useful alternative model (Moughan et al, 1984Picard et al, 1984;Smith et al, 1990;Donkoh et al, 1994) and is used in practice. The rat may be particularly useful for quality control purposes.…”