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    Studies of variation in the rectal temperature, pulse rate, respiration rate and skin temperature of some New Zealand Jersey cows with particular reference to summer climatic conditions : a thesis presented in partial fulfilment of the requirements for the degree Master of Agricultural Science in the University of New Zealand
    (Massey University, 1959)
    The field of research known as Environmental Physiology covers Studies on the physiological responses of animals to variations in their immediate environment and on the adaptation of animals to environment. Generally, studies with cattle in this field have been pursued either in tropical environment or, lately, in very cold climate (see series of papers by MacDonald and Bell, 1958). The use of climatic chambers, such as those described by Brody (1948) and by Findlay (1950), has enabled research workers to study the effects on animals of a wide range of climatic variables but the results have a restricted application in the field. [From Introduction]
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    Coefficients of inbreeding and relationship among pedigree Jersey bulls used in artificial breeding or in natural mating in New Zealand : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science in the Victoria University of Wellington, Massey College
    (Massey University, 1962) Hamilton, C O
    Since 1950, when the New Zealand Dairy Board assumed responsibility for the commercial development of Artificial Breeding, there has been a tremendous increase in Artificial Breeding usage. Whereas in 1950,0.2% of the total cow population was artificially inseminated, the corresponding figure for 1960 was 26%. In any Artificial Breeding scheme there are dangers of inbreeding through the use of a limited number of sires, and if the young sires selected for the scheme are largely the sons of the best sires already in the scheme, then the dangers of inbreeding are increased. Inbreeding to high levels is undesirable because it generally reduces the mean level of all characters closely connected with fitness in animals and leads in consequence to loss of general vigour and fertility. Since most characters of economic value in demestic animals are aspects of vigour or fertility, inbreeding is generally deleterious. The genetic basis of this inbreeding degeneration is not completely clear. Another harmful effect of inbreeding is the possibility that it may fix undesirable genes in the homozygous state.
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    The influence of importations on the New Zealand pedigree Jersey breed and the level of inbreeding, 1895-1950 : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science of the University of New Zealand
    (Massey University, 1952) Jhala, Girish Manilal
    Of the 1,845,000 dairy cows in milk in New Zealand in January 1950, 85% were either purebred or grade Jersey cattle (A & P Statistics 1950). With the exception of the Island of Jersey no other country has such a predominance of this breed and it is of interest to both the animal husbandman and the geneticist, to trace not only the growth of the breed in this country but also the changes in its structure during the last half century. There is at present no authoritative information available relating to the breeding methods employed by New Zealand dairy farmers and the lack of comprehensive records of performance in the Jersey breed as a whole makes it unlikely that the selection policies of the last fifty years will ever be adequately presented. The dependence of the more popular breeders on the importations during the present century is, however, generally recognised but no attempt has yet been made to measure the influence of these much popularised animals on the breed as a whole. If imported animals differ in their genotype from New Zealand-bred animals, then a general preference for the former or their descendents should gradually change the average genotype of the breed. That such a preference exists is suggested by Fahimuddin (1952). He found that the Jersey breed was divided into strata and that the herds using imported sires were in the upper and the most important strata. There is no way of calculating whether imported and New Zealand-bred animals do differ genetically, but estimates of the proportion of the genes in the breed as a whole for which imported animals are ultimately responsible are of interest for several reasons.
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    Genetic changes in a New Zealand pedigree Jersey herd : being a thesis presented in partial fulfilment of the requirements for the degree of M. Agri. Sc., Massey Agricultural College, University of New Zealand
    (Massey University, 1952) Ecka, S T
    The majority of sires used in New Zealand herds are obtained from pedigree breeders and in consequence, the genetic merit of the national herd depends largely upon the quality of the pedigree section of the cattle breeding industry. The continued use of pedigree sires by many commercial farms has probably resulted in a narrowing of the genetic margin between registered and non-registered dairy cattle. Upon this genetic margin the present elite status of pedigree cattle depends and if it were possible to demonstrate that this margin was negligible then the present rigid distinction between pedigree and non-pedigree stock would not be justified. This would have far reaching implications the most important of which would be that there would be little justification in restricting sires used in the industry to those bred in pedigree herds. On the other hand if it were possible to demonstrate that pedigree herds were improving genetically and preserving a genetic margin over commercial herds then the present policy of attempting to effect national herd improvement through the pedigree section of the industry would be vindicated.
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    An analysis of the 1948 Jersey heifer registration data to provide information concerning some features of New Zealand pedigree Jersey cattle
    (Massey University, 1952) Fahimuddin, Md
    At present there is a lack of information concerning the breeding methods practised by owners of pedigree dairy cattle in New Zealand. This deficiency is a serious handicap in attacking some of the major problems facing the dairy industry in this country. Since the emergence of the Dairy Board in 1936 as the main national force concerned with herd improvement a great deal has been achieved in the field of dairy cattle improvement and the evolution of a sire survey applicable to conditions obtaining in New Zealand is one of the major achievements of the Dairy Board. But many aspects of the pedigree industry which provides the majority of sires used in the Dominion remain to be elucidated. For example, the present scarcity of proven sires, and the more or less stationary level of production of commercial herds are some of the problems which have direct bearing on the pedigree section of the dairy industry. These facts alone illustrate the importance of the study of current breeding methods and of the pedigree system as it exists in New Zealand. Many investigations relating to dairy cattle breeding have been carried out overseas. Although many of the problems studied are encountered in New Zealand, the Dominion's typical grassland farming and the seasonal dairying associated with it limit the usefulness of such investigations. With more information becoming available breed societies are beginning to adjust themselves to a new phase of cattle breeding. The increasing emphasis on production as an aid to selection, and the acceptance of artificial insemination are two phases in which a change of attitude is desirable. The rapid growth of pedigree herds, the more frequent appearance of performance details in pedigrees and the increasing number of pedigree animals mated artificially each year illustrate this gradual change.
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    A study on the inheritance and phenotypic and genetic interrelationships among some physiological and productive variables in Jersey cows : a thesis presented in partial fulfilment of the requirements for the degree of Master of Agricultural Science, Massey University of Manawatu, New Zealand
    (Massey University, 1964) Sharma, S P
    Field studies were made on mixed age, lactating Jersey cows (130 dams and 143 daughters) from 18 herds in the district of Manawatu (New Zealand) during the summer of 1963-64 with the following objectives : (i) to measure the variation present in the physiological variables ; (ii) to estimate the heritability of the physiological variables ; (iii) to estimate phenotypic correlations between the physiological variables ; (iv) to estimate genetic correlations between the physiological variables ; (v) to estimate phenotypic correlations between the physiological variables and the productive variables ; and (vi) to estimate genetic correlations between the physiological variables and the productive variables.