Milk yield and aspergillus flavus contamination load of selected dairy meal from Mbale and Soroti fed to the lactating cows at Arapai campus farm Soroti District

Abstract

The objective of the study was to assess the milk yield and Aspergillus flavus load of dairy feeds from Mbale and Soroti Cities, the study was conducted at Arapai Campus Farm Arapai, Sub county Soroti District in Eastern Uganda between November and December 2020. Milk yield was determined by feeding different dairy meals to different lactating cows and their respective milk production recorded on a daily basis and the level of Aspergillus flavus was assessed by culturing the feed samples on rose Bengal agar amended with ox tetracycline, after inoculation, the pour plates were kept in darkness for five days before colony counting took place. The cows that fed on the dairy meal from Soroti had milk production of 3.0 liters maximum average and the cows that fed on the dairy meal from Mbale had a maximum average of 3.5liters and the cows that were not fed on any of the meals had the lowest milk yield with a maximum average of 2.0 liters. The composite feed samples from Soroti had higher Aspergillus flavus levels of 110, 125 and 168 colony forming units (all above the WHO limits) and the composite feed sample from Mbale had 23 and 19 colony forming units with 3 and 2 samples both out of four samples being positive for Aspergillus flavus from Soroti and Mbale respectively. The study revealed that cow that fed on a dairy meal with higher Aspergillus flavus levels had lower milk yield and the cows that fed on a dairy meal with lower levels of Aspergillus flavus had higher milk yield hence farmers and feed sellers are called upon to observe all the measures needed to prevent the occurrence of Aspergillus flavus in animal feeds like proper drying and good storage of feeds and feed ingredients.