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Lactotransferrin is an iron-binding protein. It has been purified from buffalo colostrum. The purified lactotransferrin has been crystallized in 10% ethanol solution. The crystals are orthorhombic and the space group is P2(1)2(1)2(1) with unit cell dimensions a = 161.70 A, b = 155.75 A, c = 113.48 A. The asymmetric unit contains three molecules of the protein with a solvent content of about 59%. The crystals were stable in the X-ray beam and diffract beyond 3.5 A resolution. The native data have been collected and the structure determination is in progress.

Survival from birth to 1 month, 1 month to weaning, weaning to 1 year and birth to 1 year was studied in crosses of native carpet wool breeds (Chokla, Malpura and Jaisalmeri) with Rambouillet. Least-squares analysis of data considering survival as 1 and mortality as 0, showed that the year and season of birth affected survival significantly during all age periods except from birth to 1 month and from 1 month to weaning where season had no significant effect. Sex (studied only for pre-weaning survival), ewe's weight at lambing and birth weight of lamb did not influence survival except that the ewe's weight a significant influence on survival from 1 month to weaning. Genetic groups did not differ significantly. Rambouillet X Malpura F1s had a higher survival rate than the other 2 F1s. There was a non-significant decline in survival with an increase in Rambouillet inheritance, except that 5/8 Rambouillet -3/8 Chola crossbreds had a slightly higher survival rate than Rambouillet X Chokla F1s. Interbreeding F1 and 3/4 crossbreds did not result in any significant decline in survival. The results show that the introduction of exotic fine-wool inheritance up to 50% and interbreeding of halfbreds will not result in any decline in survival.

Effects of genotype and ethanol consumption by pregnant mothers on hemoglobin (Hb) and red-cell levels of adenosine triphosphate (ATP), 2,3-diphosphoglycerate (DPG), and glutathione (GSH) of their progeny were studied in mice. Three lines of mice were used, one selected for high body weight, another selected for low body weight, and an unselected control. An ethanol solution [10% (v/v)] was given ad lib to the females at the time of joining them with males and continued through the pregnancy. Another group received distilled water for drinking throughout. Blood samples from the progeny of both these groups were taken at 10 weeks of age and analyzed for Hb, ATP, DPG, and GSH levels. Alcohol drinking during pregnancy resulted in lower levels of DPG in the red blood cells of progeny of the lines selected for high and low body weight and the reverse in the unselected line. Maternal alcohol consumption had no effect on Hb, APT, and GSH levels in the red blood cells of the progeny of any of the three lines. Females of both selected lines had higher levels of DPG than males. Artificial selection for body weight resulted in a positively correlated response in the level of red-cell DPG and GSH in the progeny.

A review is presented of the genetic and physiological aspects of growth, body composition and feed efficiency in mice. The genetic parameters considered are: nature and extent of within and between-line genetic variation for body weight and growth rate; direct and correlated responses to selection for body weight, weight gain, feed intake and feed efficiency; direct genetic effects of the offspring (gO); maternal genetic effects (gM); heterosis in the offspring (hO); maternal heterosis (hM), and recombination effects in the offspring (rO). The physiological parameters considered are energy requirements for maintenance and growth. The role of thermoregulatory thermogenesis in relation to the partitioning of metabolizable energy between maintenance and growth requirements of large and small mice is emphasized. The relationship of feed efficiency with other traits is reviewed at length.

Genetic groups year and season of shearing, sex and ewe's weight at lambing accounted for a significant proportion of variation in first and second 6-monthly greasy fleece weights of Rambouillet crosses with Chokla, Malpura and Jaisalmeri (F1, F2, 5/8, 3/4 and 3/4 interbreds), except that season did not influence significantly the second 6-monthly greasy fleece weight. Sex was not included in the analysis of the second fleece weight. Comparisons among genetic means showed that: (i) Chokla crosses were superior to the other crosses; (ii) there was a small and non-significant decline in both the greasy fleece weights with an increase in level of Rambouillet inheritance; (iii) interbreeding halfbreds and 3/4 breds resulted in a small and non-significant decline in fleece weight, except in Rambouillet x Chokla crosses for the second 6-monthly clip, where the decline was significant. The results indicate that crossing Indian carpet wool breeds with Rambouillet will improve greasy fleece production. Exotic fine wool inheritance should be stabilised at 50% and further improvement be brought through selection among the halfbreds.