EFFECT OF SEASON ON AFLATOXINS LOAD OF SELECTED FEEDSTUFFS FOR PIGS IN THE HUMID TROPICS

Thesis Abstract

The effect of seasons on aflatoxins loads of selected pig’s feedstuffs in the humid tropics was investigated, the feedstuffs sampled were cassava peels, bambara nut waste, palm kernel cake and brewer spent grains. The study lasted for thirty-two weeks. These feedstuffs were collected in two piggery farms in each of the six LGAs that make up Nsukka zone of Enugu State, in both dry and rainy seasons.The collected feedstuffsamples were analyzed in the laboratory for aflatoxins concentration levels using AOAC method of thin-layer chromatography (TLC)with some modifications. Data were collected from the aflatoxins laboratory analysis of these feedstuffs and with a structured questionnaire.The results of this study indicated the presence of aflatoxins in all the sampled  feedstuffs, however the lowest concentration of aflatoxins which is 0.011ppb is obtained in cassava peels and bambara nut wastes while  the highest concentration of aflatoxins obtained is 0.055ppb in brewer spent grains,these values are within the tolerance limit in Nigeria for total aflatoxins (B1+B2+G1+G2),which is 20ppb.The obtained aflatoxins levels are within range and poses less risk to pigs and pork consumers.The results also shows that there were no significant difference (P > 0.05) on the aflatoxins concentration levels of the feedstuffs at their sources, across the piggery farm locations, in the season and source of feeds interactions, season and the piggery farm locations interactions, as well as season and feedstuffs interactions. However the main effect of seasonon aflatoxins level which is 0.022ppb and 0.044ppb in the dry and rainy seasonrespectively were highly significant (P < 0.01).Also the main effect of aflatoxins of the feedstuffs were highly significant (P < 0.01) except in brewer spent grains were it is significant (P < 0.05). It follows that the aflatoxins  levels according to season in the comparison between the source of feedstuffs and the piggery farm locations for the sampled feedstuffs were highly significant (P< 0.01) especially in the rainy season, except bambara nut wastewhich is highly significant (P< 0.01) in the dry season. There were higher values in the aflatoxins levels in all the feedstuffs sampled in the rainy season than in the dry season.It was therefore concluded that season has an effects on the aflatoxins level of pig’s feedstuffs with rainy season  favouring toxigenic mould metabolism and growth in the feedstuffs which produces aflatoxins as their metabolites than in the dry season in this study, hence adequate preservative measures, proper feed handling and storage should be adopted. It is therefore recommended that piggery farmers should adopt adequate preventive measures and also apply the various preservative storage methods in order to reduce the aflatoxins levels infeedstuffs especially in the rainy season for better performance of the pigs and safety of pork consumers.