Abstract:
GEOGRAPHICAL AND CHRONOLOGICAL OCCURRENCE OF SUBSTANDARD HERD MILKS IN SOUTH EAST QUEENSLAND G.K. REASON and I.H. RAYNER 1. Milk of substandardcomposition is a technical and economic problem for the farmer and for the industry. Data collected in a survey of the composition and freezing point of bulk milk supplied by a 10% sample of milk producers has been analysed. The data collection area comprises three regions in South East Queensland which supply over 60% of the State's liquid milk market. 2. Over a two year period 670 samples were taken from suppliers in the Moreton 2 region. Approximately 70% of the total milk output of these suppliers 'enters the liquid milk trade. A further 769 samples were taken from suppliers in the Moreton 1 region and 1122 samples from suppliers in the- Darling Downs region. Suppliers in both these areas sell approximately 35% of their total milk output for consumption in liquid / form. 3. The percentage of substandard samples was:- Relevant standards are: butterfat 3.3%, total solids 12.0%, solidsnot-fat 8.5% and freezing point -0.540�C. The freezing point value is the 'normal' milk standard used to estimate added water. Of the 6.9% of samples from the Downs which were subnormal for butterfat, 66% were received in the August to November period. Because of cropping based feed programmes in that area,. levels of available dry matter and fibre are often low at that time. This period also coincides with the first three to four months of lactation for the majority of cows. Low total solids in the August to-October period accounted for 52% of the substandard samples from the Moreton 1 region, 47% from the Moreton 2 region and 57% from Ehe Downs region. Of the substandard S.N.F. tests recorded in the Moreton 1 region, 31% were in the June to July period, with an additional 26% in the August to October period. Of the samples from the Moreton 2 region, 38% of the substandard S.N.F. values were recorded from August to October and a further 31% in February to April. In the Downs region, 57% of the samples substandard for S.N.F. were recorded in the August to October period. There was no obvious seasonal pattern in the results of freezing point testing. Department of Primary Industries, Brisbane, Queensland. 28P
