Js. Hogan et al., Bacterial counts associated with sawdust and recycled manure bedding treated with commercial conditioners, J DAIRY SCI, 82(8), 1999, pp. 1690-1695
Bacteria counts associated with untreated organic bedding materials were co
mpared with those of bedding treated with either an alkaline commercial bed
ding conditioner, acidic commercial bedding conditioner, or hydrated lime.
Bedding materials were recycled manure and kiln-dried sawdust. The effects
of bedding treatments on bacteria counts differed between bedding types. Ea
ch of the bedding treatments significantly reduced bacteria in recycled man
ure prior to use. The alkaline conditioner and hydrated lime effectively in
hibited bacteria in recycled manure for 1 d. Bedding counts and teat swabs
of cows housed on recycled manure treated with the alkaline conditioner wer
e reduced on d 2. The use of the acid conditioner in recycled manure had li
ttle effect on bacteria in bedding. Sawdust differed from recycled manure i
n that bacteria in untreated sawdust prior to use were minimal, and populat
ions increased rapidly during the first 2 d after use as bedding. The acid
conditioner had a bacteriostatic effect in sawdust, evident by the reductio
n of bacteria on d 2. The alkaline conditioner and hydrated lime did not al
ter bacteria counts in sawdust compared with untreated sawdust. Antibacteri
al activity of each conditioner deteriorated between d 2 and d 6 in both be
ddings. The antibacterial activities of conditioners were related to the pH
of bedding materials. The use of commercial bedding conditioners initially
reduced bacterial counts; however, the antibacterial effects had diminishe
d between d 2 and 6 after use in bedding.