A Comparison of Milk Production and Its Relation to Lamb Growth in Five Breeds of Sheep

Abstract

Milk production from ewes of five breeds of sheep (Suffolk, Hampshire, Rambouillet, Canadian Corriedale, and Romnelet) and the growth of lambs suckling these ewes were compared. Milk production was measured by weighing the lambs prior to and after nursing and crediting the gain in weight to milk produced. Ewes nursing twins produced more milk than those nursing singles (P <.01). Among ewes nursing singles, Suffolk produced the greatest amount of milk (P <.01). Milk production from ewes nursing twins was greatest (P <.05) in Canadian Corriedale and Suffolk ewes. It is suggested that the milk drawn by twin lambs is a measure of milk production while that drawn by single lambs is a measure of ad lib. consumption.Single lambs gained more body weight than twin lambs (P <.01) but differences between breeds were not consistent. Gain in body weight of lambs varied with the milk consumed and, also, may have been influenced by differences in creep-feed consumption.The significant correlation coefficients between milk production and body weight gain of twin lambs in four of the five breeds suggests that milk production is a major consideration in determining the body weight gain of lambs, although other factors also apparently influence body weight gain of the lambs. Since no differences were found in the protein or fat content of the milk (P >.05), it would appear that these factors had little influence on the body weight gain of the lambs or its correlation with milk production.

Relationships between Ewe Milk Production and Composition and Preweaning Lamb Weight Gain

“…None of the regressions of G on PMP or PMF was significant, in either single lambs or twins. Our results are in agreement with those obtained by , Slen et al (1963) and Moore (1966) that there was little improvement in the relationship between milk intake and growth rate when MP was expressed in terms of components rather than whole milk. Scales (1968), however, reported a highly significant correlation between fat intake and lamb growth in Romney lambs but not in Corriedales and Merinos.…”

“…This value is within the range reported in other studies, such as 25% (Addleman et al, 1964), 22% (Barnicoat et al, 1949b), 22% , 13 to 33% , 35% (Peart et al, 1972) and 18 to 41% (Slen et al, 1963). The ability of twin lambs to more completely evacuate the udder early in lactation has been cited as the main factor explaining this difference .…”

“…There were no significant differences among breeds for percent fat. Addleman et al (1964) and Slen et al (1963) reported no significant differences among breeds for either percent protein or percent fat. , however, found a significantly higher percent of fat in the milk of Romney than.…”

“…The We publish these equations and associated r 2 values, however, to aid investigators who might wish to estimate milk production, which is costly and difficult to measure, from lamb weight gain, which is much easier to measure. (1955), Barnicoat et al ( , 1956d, , Munro (1962), Slen et al (1963), Folman et al (1966a, 1966b, Moore (1966), Peart (1967, Scales (1968), Butterworth et al (1968, Robinson et al (1969), Acharya andBawa (1971), Geenty and and Peart et al (1975) that ewe milk production is the most important variable influencing lamb weight gain in the early stages of lactation but that the effect of milk production tends to decline as lambs become more dependent upon the intake of forage or grain. With MP in the model for single lambs, the regression coefficient of total lactation G on PMP was large and positive.…”

Growth of young rats after birth

“…Similar findings are known for other animals e.g. sheep (Langlands, 1972;Wallace, 1948;Thomson & Thomson, 1953;Slen et al, 1963;Peart, 1967;Allden, 1968), cattle (Wardrop, 1968), deer (Thompson et al, 1973;Robinette et al, 1973).…”