Evaluation of detoxicated Jatropha curcas meal in finishing pig diets

Author(s)

Bernardo Berenchtein

• Document type: Doctoral Thesis
• Press: Piracicaba.
• Institution: Universidade de São Paulo (USP). Centro de Energia Nuclear na Agricultura (CENA/STB)
• Defense date: 2012-05-30

Examining board members

Adibe Luiz Abdalla; Dirlei Antonio Berto; Ives Cláudio da Silva Bueno; Helder Louvandini; Simone Mendonça

• Advisor: Adibe Luiz Abdalla

Abstract

The pourpose of this study was assess the inclusion of detoxicated Jatropha meal (Jatropha curcas L.) in the diet of finishing pigs. Initially it was used in a biological assay with Wistar rats. The analysis of variance did not detect (P>0.05) effect of the addition of DJCM over the performance variables, being, however, observed a significant reduction (P<0.05) on digestibility of diets in response to the addition of the DJCM. The relative weights of liver, kidneys, heart, intestine and length of the small intestine of the animals fed with the different treatments did not differ significantly (P>0.05) with the inclusion of DJCM. For the relative weight of the total gut (intestines plus small intestine) and the small intestine it self, a linear increase was observed (P<0.05) due to the increased level of inclusion of DJCM in the diet. The analysis of variance also did not detect (P>0.05) effect of the addition of DJCM on blood variables, as well as in the hepatic enzymes. In a second trial, there were investigated the contents of forbol esters (FE), total phenolics (TP), total tannins (TT), condensed tannins (CT) saponins (SPN), amino acid profile, and apparent digestibility of DJCM for finishing pigs, as well as the biogas and methane generated by the waste of pigs fed the basal diet (BD) and BD plus 8% of DJCM (DB8). The contents of FE, TP, TT, CT and SPN observed were, respectively, 0.06 mg/g, 26.08 and 10.43 gram equivalent of tannic acid, 0.05 gram equivalent of leucocianidin and 0.005%. As for the apparent digestibility results obtained, it was found values of 83.8%, 3.5 kcal/kg, 13.5%, 1.5% and 2.3% respectively for apparent digestible of dry matter, energy, protein, fiber and ethereal extract. In relation to the production of biogas and methane generated by the waste products from pigs, it can be concluded that the use of DJCM did not affect significantly (P > 0.05) the production of these gases in experimental. Subsequently, it was then evaluated the effects of levels (2, 4, 6, 8%) of DJCM at the diet of finishing pigs upon the performance parameters, carcass characteristics, meat quality and toxicity of DJCM. The inclusion of DJCM presented negative quadratic responses (P < 0.001) for the final weight; daily weight gain and daily consumption of ration. Although there has been a reduction in performance depending on the inclusion of DJCM, it is important to note that when comparing treatment outcomes of control (0%) and the addition of 2% of DJCM, it was not observed significant difference (P > 0.05) for the variables final weight, daily weight gain, feed conversion and only significant reduction (P < 0.05) in the daily ration consumption. The inclusion of DJCM showed negative linear responses (P < 0.05) for warm carcass yield, average thickness of fat and loin eye area. It was found negative quadratic responses (P < 0.05) for the length of the carcass. After the specific contrast analysis comparing the control treatment (0%) and the addition of 2% of DJCM in diet, not significant difference was observed (P > 0.05) between treatments. In relation to the quality of the meat, there was no significant effect (P > 0.05). For the liver enzymes evaluation, ALT has not changed (P > 0.05) with the inclusion of DJCM, however, for AST, the inclusion of co- product caused negative quadratic responses (P < 0.05). For concluding the work, it was evaluated the enteric methane emission by finishing pigs fed with diets with the addition of 2% of DJCM. The inclusion of this co-product reduced significantly (P > 0.05) the enteric methane emissions by pigs. With the results obtained in this work, it can be concluded that, although the inclusion of DJCM may promote some deleterious aspects, in general, the DJCM may be included up to 2% in finishing pig diets. (AU)