Quality of ewe milk as affected by stocking density and litter treatment with bentonite

Three groups of 12 lactating Comisana ewes were housed in separate rooms in the same building. Two rooms were 18 m(2) straw-bedded pens and the third had a total area of 24 m(2). Three treatments were tested: low stocking den sity (LD 2 m(2)/animal); high stocking density (HD = 1.5 m(2)/animal); high stocking density with a fortnightly application of 0.5 kg bentonite per m( 2) of Litter (HDB). Air concentrations of micro-organisms were determined t wice weekly inside each room. Ewe milk yield was recorded daily and individ ual samples were analysed weekly for milk composition, renneting properties and bacteriological characteristics. Treatment I-ID resulted in higher air concentrations of total micro-organisms and of yeasts/moulds than treatmen ts HDB and LD and higher amounts of coliform bacteria than treatment LD. Ew es in the HD group produced milk with a lower casein, fat and lactose conte nt compared to LD animals, whereas no differences in milk constituents were found between HD and HDB ewes. Renneting properties were improved and soma tic cell and bacterial counts were lower in treatments LD and HDB as compar ed to treatment HD. These findings indicate that increased stocking density can reduce the cheese making efficiency of ovine milk and suggest that lit ter treatment with bentonite can partially alleviate adverse effects of red uced space on both renneting ability and the hygienic quality of ewe milk.