Teatcup Liner Research Articles

649. The effect of design of teat-cup liners on mastitis incidence

1. An experiment was carried out to study the effect on udder health and milk yield when half-udders of dairy cows were milked with either a moulded or an extruded teat-cup liner.2. There was a higher incidence of mastitis in quarters that were milked with moulded than with extruded liners, but the incidence of new infection was similar for each group of quarters.3. The types of liners used had no measurable effect on teat orifice erosion or leucocyte content of the milk, nor was the decline in milk yield with advance in lactation significantly different for the groups of quarters.We wish to thank Dr A. T. R. Mattick and Mr A. S. Foot for advice and encouragement, and Miss H. R. Chapman for assistance in the cleaning of teat-cup liners. We are indebted to Miss M. S. Hawkins and Messrs T. M. Higgs and D. S. Simpkin for technical assistance.

BACTERIAL COUNTS OF MILK AS AFFECTED BY INCONSPICUOUS DETERIORATION IN MILKING MACHINE TEAT-CUP LINERS

Used teat-cup liners, appearing in reasonably good physical condition but having microscopic breakdown of the inside surfaces, were compared with new liners with respect to effect on the bacterial counts of milk. Under similar practical conditions, milk from units equipped with the used liners sometimes had considerably higher counts than milk from the new liner units. When the contamination level was low there was little consistent difference in milk counts.

581. The deterioration of milking rubbers: V. The effect of rubber composition

The importance of fat absorption as a cause of deterioration in the rubber teat-cup liners of milking machines has already been demonstrated (l, 2), and it is well known that the composition of the rubber affects its resistance to fat. It was considered desirable, therefore, to see what changes in composition could usefully be made, and how these would affect fat absorption under normal milking conditions. To this end, and with the cooperation of a large number of farms and Milk Production Officers, the four experiments reported here were carried out.

532. The relationship between mastitis and the method of stripping after machine milking

At the end of normal machine milking some milk, which cannot be removed unaided even by the most efficient milking machine, remains in the udder sinus. This milk, often some 10% of the total yield depending upon the age of the cow, udder shape, partial vacuum of the milking machine and teat-cup liner design, was formerly most frequently removed by hand. As a result of advice and encouragement farmers are rapidly changing to manipulation of the teat-cups, known as machine stripping. This practice has renewed interestin the old controversy about the effect of the method of stripping on udder health.

529. Pulsation and milking rate

The pulsator mechanism of the double-action milking machine causes the rhythmical expansion and collapse of the rubber teat-cup liner during milking by alternately applying a partial vacuum (usually 13–15 in. Hg) and admitting atmospheric air to the space between the rubber liner and the teat-cup shell. The inside of the liner is subjected to continuous partial vacuum.

Contamination of Milking Machine Teat-Cup Liners as Affected by Inconspicuous Deterioration of the Interior Surfaces ,

Contamination of Milking Machine Teat-Cup Liners as Affected by Inconspicuous Deterioration of the Interior Surfaces ,

Methods for Studying Factors that Influence the Sanitary Condition of Milking Machine Teat-cup Liners1,2

Summary Since surface characteristics of rubber, combined with physical manipulation, may influence bacterial contamination of teat-cup liners, methods developed for sanitation studies incorporated a flexing action of the liners under partial vacuum, as occurs in practical operation. A modified “artificial udder” and “milking” technique was utilized for the contamination of liners in the laboratory. Bacterial counts of liners contaminated by this means were in the same general range as that of liners contaminated under practical conditions. Contamination was reasonably uniform in each of the four liners in a set and in separate sets of four liners contaminated from the same lot of milk.

449. The deterioration of milking rubbers: I. The effect of micro-organisms

It has been shown that, although they are present, sulphur bacteria and streptomyces able to oxidize rubber do not affect the life of the rubber teat-cup liners of milking machines.