Growth and performance curve of dairy goats fed with detoxified castor bean cake by different alkaline solutions

Abstract: This study aimed to evaluate the influence of the substitution of soybean meal (SM) by detoxified castor cake (DCC) by two alkaline products on intake, performance and on the growth curve of goat?s kids. 24 were used, Saanen goats (n=12) and Anglo Nubian (n=12), with initial body weight of 16.2±0.67 kg, initial age of 3 months and confined during the growth phase. The treatments consisted of three diets: a standard diet formulated with a traditional protein source, the soybean meal (SM); and test diets, which consisted of a protein source alternative, differing detoxification processes, on the basis of calcium hydroxide (Ca(OH)2) or sodium hydroxide (NaOH). The animals were distributed in a completely randomized design, in factorial 3 x 2 (diet SM, Ca(OH)2 DCC and NaOH DCC x Saanen and Anglo Nubian) totaling six sessions with four replicates each. The experimental period lasted 270 days. The non-linear models used were the Gompertz and Logistic. There was no effect (P 0.05) of breeds and interaction between both factors. The intake of DM during the phase of growth was greater for the goats fed with SM. There was no effect (P>0.05) of diets nor of the breeds in the ADG. Feed conversion was influenced (P 0,05) das racas e interacao entre ambos os fatores. O consumo de MS durante a fase de crescimento foi maior para as cabras alimentadas com FS. Nao houve efeito (P > 0,05) das dietas nem das racas no GMD. A conversao alimentar foi influenciada (P < 0,05) pelas dietas, em que as cabras que consumiram as dietas com TMD apresentaram melhor conversao alimentar. Observou-se que ambos os modelos tiveram bons ajustes, com valores numericamente superiores a 90%, contudo, o modelo Logistico apresentou maior R2 e, ao mesmo tempo, indice assintotico (IA). Apesar do GMD ser igual, as racas apresentaram taxa de crescimento absoluto (TCA) diferenciado ao longo do tempo, onde as cabras Saanen atingiram o pico primeiro (181 dias), com TCA de 0,14 kg dia-1. Porem, mesmo as cabras Anglo Nubianas atingindo o pico mais tardiamente, a TCA foi maior, cerca de 0,16 kg dia-1 superior as Saanen. Ambas as tortas tem potencial de substituir o FS em dieta de cabritas de aptidao leiteira durante a fase de crescimento. O modelo matematico Logistico estima de forma mais precisa o crescimento de cabras Saanen e Anglo Nubiana, sendo que a taxa de crescimento absoluto e maior em cabras Anglo Nubianas.