Number of sweat glands per unit area of skin, their size, and their depth below the epidermis were compared in skin biopsy specimens obtained from the midside region of two Zebu and three European breeds of dairy cattle. Within Zebu breeds, comparisons were made between sweat glands from the midside and the dewlap. Zebus were found to have much larger and more numerous sweat glands than European animals. Within Zebus, sweat glands were slightly larger, and much more numerous, on the midside than on the dewlap. They are much closer to the skin surface in Zebu cattle than in European. In Zebus sweat glands are longer and of greater diameter than in European cattle. In appearance they are sac-like, with few convolutions, whereas sweat glands in European cattle are rarely sac-like, and quite convoluted.

Occasions of unduly heavy and prolonged rainfall during the period April 1946 – July 1951 resulted in the occurrence of fleece-rot in sheep of the Field Station flock in each of the six years. Data obtained from periodic examinations of the flock have been related to the nature of climatic conditions associated with outbreaks of the disease. They show that when rain occurs in falls of sufficient intensity and frequency to wet sheep to the skin for a period of a week or more, fleece-rot may be expected to develop in some of them. The longer the period for which the sheep are kept wet, the greater the number in a flock which will be affected. Fleece-rot was experimentally induced in four out of five Merino sheep known to be susceptible to the condition, whereas five animals known to be resistant were unaffected by the same treatment. Microscopic examination of skin sections taken from naturally occurring cases revealed the presence of a dermatitis. A similar condition was observed in skin sections from the animals in which fleece-rot was experimentally induced. Young sheep were found to be more susceptible than old. There was no association between degree of wrinkling and susceptibility or between 'grip' and susceptibility. When subjectively-appraised attributes of the fleece were related to the occurrence of fleece-rot, confusing results were obtained. However, when measured fleece data, obtained from a group of Merino sheep which had been under observation for four consecutive years, were considered, it was found that those for clean-scoured yield, wax and suint ratio, and density of fibre population per unit area of skin surface, were related to resistance or susceptibility. Nevertheless, a number of animals were found which were susceptible or resistant to the disease despite the nature of their fleece attributes. Differences in susceptibility were found between families of Merino sheep. These are associated with between-family differences for the fleece attributes found to be important in fleece-rot reaction.

Although work has been published showing relationships between milk production of the ewe and growth of the lamb, little has been done to investigate the effects of physical impairment or deficiency in mammary function in the ewe on the survival and growth of the lamb. This point has been studied by examining data for survival, birth weight, daily gain in weight to weaning age, and weaning weight from 621 Merino lambs born in the F. D. McMaster Field Station, C.S.I.R.O., flock from 1946 to 1949. When the performance of lambs from ewes having impaired or imperfect udder function was compared with that of lambs whose dams had normal function it was found that the lambs from ewes having defective function had a lower survival rate, a lower daily gain in weight to weaning age, and lower weight at weaning. The differences were statistically significant. Examination of the dry ewe flock in 1946 revealed that approximately 6 per cent. of all ewes aged from 1 to 7 years had damaged or imperfect udders. There was an association between age and incidence of defective udders, the incidence being highest among the oldest ewes. Culling of affected ewes from the flock was found to have very little effect in increasing the overall percentage of lambs raised to weaning age, or increasing their weaning weight. It is doubtful if culling for this fault would be beneficial in the average commercial Merino flock.

Observations were made of a number of skin characters in five breeds of European (Bos taurus L.) dairy cattle. Skin samples were taken from the cattle in January and July. There were differences between breeds in sweat gland volume and length! diameter ratio, in skin and papillary layer thickness, in the ratio skin thickness/papillary layer thickness, and in the degree of shrinkage in transverse sections cut from the papillary layer. There were no differences between breeds in density of follicle population (and hence sweat glands) per unit area of skin. Sweat gland volume, skin thickness, and papillary layer thickness were larger in winter than in summer, but there were no such differences for sweat gland length/ diameter ratio, the ratio skin thickness/papillary layer thickness, and follicle population density. The only significant overall correlations between characters were those between sweat gland volume and sweat gland length/diameter ratio, and sweat gland volume and papillary layer depth.

On three occasions during the period l91S-1956 field observations were made on coat shedding in B. indicus, B. taurus, and B. indicus x B. taurus cattle, and hair and skin samples taken. Measurements of hair length, diameter, and weight per unit area of skin were made, and stages of hair growth within the follicle observed. On two occasions hair data included measurements of length and diameter on individual hairs. Two shedding periods were observed. in spring and in autumn. Approximately 4 months was required for the complete change from m-inter to summer coat, the change in appearance being dramatic. Less time was required for autumn shedding and there was a less dramatic change in the appearance of the coat. Histological data from skin samples supported these observations and showed that during shedding almost all mature hairs were lost from the skin follicles. All types of cattle had characteristically short, light summer coats and long, heavy winter coats. No difference in hair diameter was observed between summer and winter coats in B. taurus, but in B. indicus hair diameter was much greater in the summer coat. In all seasons 01 the year B. indicus had the shorter and lighter coats. The minter coat in long-coated B. tauws did not appear to hare an undercoat, whereas short-coated B. taurus and B, indicus had distinct undercoats. In B. indicus x B. taurus F1 crossbreds coats were as'short in summer as those of B. indicus, and as long in winter as those of B. taurus. Differences between species in shedding, and in coat characteristics at different seasons of the year, may be of ecological importance.