Excretion of D.M., N, Ca, P and Mg in faeces, and N, P and Mg in urine were measured at intervals over 12 months in breeding Scottish Blackface sheep grazing hill pastures. These values were used with data on reproductive performance and body compositional changes, to calculate the energy, nitrogen and mineral balances. The sheep were: 11 6½-year-old with sound mouths (SM), 16 6½-year-old with broken mouths (BM), 16 5½-year-old with all permanent incisors clipped to gum level (CM) and 16 2½-year-old (Y). An energy supplement was given at the end of gestation and during early lactation. All faeces were collected and creatinine was used as an internal marker to estimate urine volume.

Faecal D.M. output ranged from 443 to 662 g/day, with highest values in November and lowest in May. Average values for the BM sheep were lower than those for the other groups but when output was expressed as a power function of body weight, the values for the Y sheep were 15% higher than those for the other groups. Faecal excretions of Ca and P in January and February were very low and the values for P were half the expected endogenous faecal loss.

Urinary output ofN ranged from 6·0 g/day in February to 22·2 g/day in August and the corresponding urinary urea N: total N ratios were 0·24 and 0·69. Urinary Mg output was highest in late summer and early winter but urinary P showed no consistent trends.

The estimated daily intakes of DOM (g) were 936 in November 1969, 599 in January, 414 in February, 1075 in May, 1150 in August and 946 in November 1970.

The loss of energy from the body between mating (November) and mid-lactation (June) ranged from 9·5 to 16·8% of the total calculated ME requirements in the Y and BM sheep, respectively. Maintenance requirements averaged 204 kJ/kg body weight/day and the value for the Y sheep was 12% higher than the mean for the older sheep.

Nitrogen and mineral balances were calculated for February, May, August and November. The sheep were protein-deficient in winter, not from a shortage of crude protein in the diet but because of its low digestibility (34%). Intakes of Ca and P in winter were low and a real possibility of a P deficiency exists. Estimates of the concentrations of N and of minerals in the herbage consumed by the sheep were made and compared with those obtained for cut herbage from the same pastures. It would appear that the sheep selected herbage of a higher protein content than that of the cut herbage. Herbage selection was greatest in November.

The seasonal changes in plasma concentrations of albumin, globulin, transferrin, urea, Ca, P and glucose were measured in 59 Scottish Blackface sheep grazing a hill pasture. The sheep were classified according to age and state of permanent incisor dentition into four groups. Sheep were slaughtered at mating (November), mid-lactation (June) and in the late dry period (November), and the changes in plasma constituents related to changes in body composition. A protein-free supplement was offered during late pregnancy.

Another group of sheep was used in the subsequent year to investigate the significance of helminth infections on such pastures.

Plasma albumin concentration fell from 32·0 g/1 in all sheep in early pregnancy to 17·5–19·5 g/1 in late pregnancy and early lactation in 5½- to 6½-year-old animals. Younger animals (2½ year old) maintained higher (23·0 g/1) levels at these latter times. The extent of the decrease in plasma albumin concentration of the groups was related to the loss of N from their soft tissues during the same period.

Plasma volume increased from 2·10 to 2·491 between early pregnancy and midlactation (45 and 66 ml/kg body weight respectively). The increase in volume was considered to account for the reduction in the concentration of plasma globulin which took place during this period.

Plasma urea-N concentrations were extremely low (50—60mg/l) between February and April and had fallen from their highest values (240 mg/1) in August to 150 mg/1 by the following November. It is argued that the fall in albumin concentration which occurred in early pregnancy, coupled with the extremely low urea-N concentration, reflects a very low digestible crude protein intake during most of pregnancy.

Transferrin concentration followed a similar seasonal pattern to urea. The concentration was extremely low in February (2·2–2·4 g/1), highest in August (3·45 g/1) and had fallen by November (3·0 g/1). The value of transferrin as a nutritional index is discussed.

Regular dosing with anthelminthic of sheep on these pastures had a beneficial effect on plasma albumin concentrations, particularly during critical nutritional periods, namely late pregnancy and lactation.

Plasma glucose, Ca and P concentrations were of no value in monitoring the nutritional status of the animal with respect to these nutrients.

One hundred and sixty-eight wool samples were collected from commercial flocks of Karadi sheep raised in the five provinces of northern Iraq. The wool characteristics dealt with were staple and fibre length, crimps, fibre diameter, medullation, fibre strength and elongation.

The results showed that the Karadi wool is a long type of carpet fleece with average staple and fibre lengths of 19·3 and 23·5 cm, respectively. It had an average fibre diameter of 48·1 μ and contained 19·45 % medullated fibres. The number of crimps per 2 cm was 2·4. Average fibre strength and elongation were 24·8 g/5 cm and 31·8 % respectively. Phenotypic correlations between wool traits were studied.

Interest is increasing in the Navy bean (or baked bean) as a breakcrop from cereals in southern England. As little experimental work has been carried out on the fertilizer requirements of this crop in the U.K. we undertook a trial in 1973 to investigate its response to four levels of nitrogen.

A field experiment was made with sorghum hybrid CSH-1 during the rainy seasons of 1968 and 1969 on a sandy loam soil to study the influence of amounts and sources of phosphate fertilizer on phosphorus nutrition. Concentration of P in the crop and uptake increased with increasing amounts of phosphate and with increasing proportions of water-soluble P in triple superphosphate-dicalcium phosphate and triple superphosphate-rock phosphate mixtures. Relative effectiveness values were calculated from P uptake at harvest by a multiple regression method. For triple superphosphate, nitrophosphate (30% water soluble P), dicalcium phosphate and rock phosphate (from Jordan) the values were respectively, 100, 74, 61 and 22.

Three preliminary experiments at Cambridge (1904–70) indicated that several varieties and breeding lines of sugar beet differed in their response to fertilizers. Three factorial experiments were therefore made at Broom's Barn (1970–2) to measure response by four widely differing varieties of sugar beet (Sharpe's Klein ‘E’, Maris Vanguard, V.T.137 and Anglo-Maribo Poly) to nitrogen (0, 75 and 150kgN/ha), sodium (0 and 250 kg N/ha) and potassium (0 and 400 kg K/ha) fertilizers. Increases in sugar yield from 75 kg N/ha by each of the varieties were remarkably similar and giving a further 75 kg N/ha neither increased nor decreased the yield of any variety on average over the three experiments. The yield response to sodium and potassium was greatest in Sharpe's Klein ‘E’ and least in V.T.137; however, as with nitrogen, varieties responded inconsistently from year to year and the interactions were not statistically significant for data pooled over the three experiments. These experiments indicate that varietal differences in fertilizer requirement are unlikely to be important in commercial practice.

An investigation was undertaken to determine whether commercial milk replacers provide fermentable substrates for the yeast Torulopsis glabrata and thus produce ethanol in the stomachs of new born lambs and calves. Samples of stomach contents from calves in two small rearing units and a small number of farm bred calves, all being fed commercial milk replacers, were also examined. Ethanol was produced from certain replacers in all cases, and its association with Torulopsis glabrata was confirmed.