Use of oyster shell as calcium supplement. Part 1. Effect on the utilization of gossypol-containing cotton seed cake by the chicken

The comparative utilization of cottonseed cake (CSC) diet supplemented with varying levels of oyster shell (0.00, 1.50, 3.00 and 4.50%) as a source of calcium, and groundnut cake (GNC) based diet were evaluated in a feeding trial using 100 day-old HYPECO broiler-chicks. The response criteria included performance, carcass traits and economics of production. The weight gains at the end of the trial were not significantly different. However, feed consumption significantly (P less than 0.5) increased with increasing dietary calcium. Feed consumption was significantly (P less than 0.05) correlated with dietary calcium levels with r = 0.96. Feed efficiency and protein efficiency ratio were significantly (P less than 0.05) better in the GNC diets than CSC based diets in spite of the oyster shell supplementation of the latter. Both nitrogen retention and apparent nitrogen digestibility were not significantly influenced. The percent dressed weight, percent eviscerated weight and the relative weights of the thigh, drumstick, chest, back, head and belly fat were not significantly influenced by the dietary treatment. Only the relative weight of the shank was significantly (P less than 0.05) influenced. The cost-benefit analysis showed that although it was chapter to formulate CSC diets, profits were identical with GNC diets when fed to the chicks. It was suggested that CSC could be a good substitute for GNC because of the ready availability of the former. Dietary calcium of up to 1.82% was beneficial in the utilization of the CSC.     

Effect of varying levels of oyster shell on serum constituents and erythrocyte indices in growing chicken fed gossypol-containing Nigerian cottonseed cake

The addition of calcium ions to iron-gossypol complex in phosphate solution has been reported to effect the removal of the soluble ferrous-gossypol complex from solution. These workers then postulated that the formation of insoluble ferrous-gossypol by calcium may explain the biological synergistic effect of calcium with iron in the inactivation of gossypol. Earlier studies by Skutches et al. indicated reduced haemoglobin, haematocrit and total serum protein in pigs fed 0.06% free gossypol diet. While other attempts at gossypol detoxification using divalent ions have been, mainly, in the form of calcium hydroxide and/or ferrous sulphate, this paper describes the dose-response relationships between dietary oyster shell (a much cheaper source of calcium than Ca(OH)2) and some serum constituents and erythrocyte indices in the chicken fed gossypol-containing cottonseed cake (CSC) diets.     

Feeding differently processed soya bean. Part 1. Effect on performance, protein utilization, relative organ weights, carcass traits and economics of producing broiler-chickens.

The comparative utilization of differently processed (roasted, cooked and oil cake) soya bean base diets and groundnut cake diet were evaluated in a feeding trial using 100 day-old Anak broiler-chicks. The response criteria included performance, protein utilization, relative organ weights, carcass traits and economy of production. At the end of the feeding trial, the average weight gains of chicks fed processed soya bean diets were significantly (P less than 0.05) higher than those fed groundnut cake and raw soya bean diets. Both feed consumption and efficiency were significantly (P less than 0.05) enhanced by processing. For example, feed consumption was highest in the chicks fed soya bean oil cake and least in those fed raw bean. Feed efficiency was best in chicks fed roasted soya bean. The relative weights [g/100 g body wt.] of the liver, kidneys, lungs, heart, gizzard and bursa were not significantly affected by the differently processed soya bean while the raw bean (unprocessed) significantly (P less than 0.01) increased pancreas weight. The dressed weight [%], eviscerated weight [%] and the relative weight of the thigh, drumsticks, chest, back and head were not significantly influenced by the dietary treatments. However, the relative weights of the shank and belly fat were significantly (P less than 0.05) affected. Cost-benefit analysis showed that the processed soya bean gave higher profit than groundnut cake diet. Among the soya bean diets, profit was in the order: roasted greater than cooked greater than oil cake greater than raw bean.