Aflatoxin B1 and M1 contamination of animal feeds and milk from urban centers in Kenya

Background: Aflatoxin M1 (AFM1) is the principal hydroxylated AFB1 metabolite present in milk of cows fed with a diet contaminated with AFB1and excreted within 12 hours of administration of contaminated feeds. Objective: This study was initiated to assess the knowledge and practices of urban dairy farmers and feed millers about aflatoxin in feeds and milk, determine the prevalence and quantify the levels of AFB1 and AFM1 in animal feeds and milk respectively from urban environs in Kenya. Methods: This work was carried out in the Department of Public Health Pharmacology and Toxicology, University of Nairobi, Kenya, between February 2006 and March 2007. Results: A total of 830 animal feed and 613 milk samples from four urban centers were analyzed for aflatoxin B1 and M1 respectively using competitive enzyme immunoassay. Eighty six percent (353/412) of the feed samples from farmers were positive for aflatoxin B1 and 67% (235/353) of these exceeded the FAO/WHO level of 5µ gKg-1. Eighty one percent (197/ 243) of the feed samples from feed millers and 87% (153/175) from agrochemical shops were positive, while 58% (115/197) and 66% (92/153) of the positive samples exceeded the FAO/WHO limits respectively. Seventy two percent (315/439) of the milk from dairy farmers, 84% (71/85) from large and medium scale farmers and 99% (88/89) of the pasteurized marketed milk were positive for aflatoxin M1, and 20%, 35% an 31% of positive milk from dairy farmers, medium and large scale farmers and market outlets respectively, exceeded the WHO/FAO levels of 0.05µ g/Kg-1. Sixty seven percent of the urban smallholder dairy farmers had no knowledge that milk could be contaminated with aflatoxin M1 and neither knew how they could mitigate against this exposure. Feed millers knew about aflatoxin B1 in grains and excretion of aflatoxin M1 in milk, but were not alleviating exposure to animals. Conclusion: There is need to create awareness and establish routine monitoring of animal feeds and milk to reduce animal and consequently human response.Key words:  Aflatoxin B1, M1, animal feeds, milk, Keny

Host range determination of tsetse fly Glossina morsitans submorsitans by bloodmeal analysis in the upper Didessa River valley (Western Ethiopia)

Enzyme linked immunosorbent assay (elisa) was employed to determine the rate of digestion of blood proteins ingested by teneral and non-teneral laboratory reared Glossina morsitans morsitans at different time intervals after feeding. This test showed that non-teneral flies digested the species distinguishing bloodmeal components faster than tenerals. At 48 hr post-feeding, the bloodmeal donor was identifiable in 87.5% of the teneral tsetse and 55.5% of non-teneral tsetse flies. Among 160 bloodmeals of G. m. submorsitans collected from the upper Didessa river valley 54.4% (87/160) were with identifiable hosts, of which warthog accounted for about 52.9 (46/87) of meals, whereas human and buffalo blood accounted for about 21.8% (19/87) and 12.6% (11/87) of the meals, respectively. Others like giraffe, goat, cattle and elephant accounted for few bloodmeals. Thus warthog appeared to be the major host for G. m. submorsitans in the study area. SINET: Ethiopian Journal of Science Volume 24, No. 2 (December 2001), pp. 229-238 Key words/phrases: Bloodmeal, elisa, Ethiopia, Glossina, Traypanosomosi

Cryptosporidium species detected in calves and cattle in Dagoretti, Nairobi, Kenya

A total of 1,734 cattle faecal samples from 296 dairy-keeping households were collected from urban settings in Nairobi, Kenya. Modified Ziehl–Neelsen staining method and an immunofluorescence assay were used to identify those samples with Cryptosporidium oocyst infection. Oocysts from positive faecal samples were isolated by Sheather's sucrose flotation method and picked from the concentrate using cover slips. Genomic DNA was extracted from 124 of the faecal samples that were positive for Cryptosporidium and was used as template for nested PCR of the 18S rRNA gene. Twenty-five samples (20 %) were PCR-positive for Cryptosporidium, and 24 of the PCR products were successfully cloned and sequenced. Sequence and phylogenetic analysis identified 17 samples (68 %) as Cryptosporidium parvum-like, four samples (16 %) as Cryptosporidium ryanae, three samples (12 %) as Cryptosporidium andersoni and one sample (4 %) as Cryptosporidium hominis. To the best of our knowledge, this is the first genotyping study to report C. parvum-like, C. andersoni and C. hominis in cattle from Kenya. The results of this study show Cryptosporidium infections in calves and cattle may be potential zoonotic reservoirs of the parasite that infects humans

Occurrence of mycotoxins in food, feed and milk in two countries from different agro-ecological zones and with historical outbreak of aflatoxins and fumonisins poisoning in Kenya

201