Animal Waste, Water Quality and Human Health

400Animal Waste, Water Quality and Human HealthTable A10.5 Cryptosporidium.Reference Prevalence (%) Concentration NotesCattle/cows/calves A wide range of prevalence is reported in variousstudies, tending to be higher amongst youngstock(Atwill et al. 1999a&b, 2006). See also chapter 3 ofthis text.Davies et al. (2005a) – 331 / gdw, (ave.) Adult cattle; represents about 10 7 oocysts per animal perdayHeitman et al. (2002) 0–12 249 oocysts / g (ave.)Hoar et al. (2001) 1.1 – Canadian adult beef cattleHutchison et al.(2004/5)5.4 19 cfu/g (g.m.) C. parvum in fresh composite farm manure, UK.max. = 3.5 × 10 3 cfu/gMcAllister et al. (2005) 18.4 – Cows (Ontario, Canada)13 – Calves (British Columbia, Canada), max. = 132,000oocysts/gMcAllister et al. (2005) 1.1 12,323 / g (max.) CaliforniaNydam et al. (2001) – – An infected calf could produce 3.89 × 10 10 oocysts in 6daysSantín et al. (2008) 8.7, 36 – Cows, calvesStarkey et al. (2005) – 1.3 × 10 5 / g CalvesSwineFerguson et al. (2009) – – Australia. Prevalence highly variable; average sheddingrates from prior studies = 14.3 oocysts/g for adultsand 472 oocysts/g for juveniles (6–8 weeks old)Heitman et al. (2002) 0 – Canada(Continued)