1. Four varieties of marrow stem kale in the first season, and thirteen in the second, were sampled on three occasions during the first half of the winter. Intervals between samplings were up to 1 month. The plants in the samples were divided into leaf, top half of the stem, and bottom half. The levels of dry matter, proximate constituents and minerals were determined in each sample.

2. The differences in composition between the three main fractions of the plant were highly significant for all the chemical constituents, except magnesium. The values for the chemical constituents in the top half of the stem were intermediate between those of the leaf and the bottom half of the stem for most constituents; it had the lowest values for dry matter and the highest for potassium and phosphorus. The distribution of chemical constituents between the whole stem and the leaf were similar to those reported previously.

1. A feeding trial was carried out using fortyeight Large White pigs, individually fed in a Danish type piggery. Six different diets prepared at two levels of digestible energy and three levels of crude protein were fed to eight replicates consisting of four hogs and four gilts per replicate. A record was maintained of the weekly live-weight gain and food was given at a defined restricted level in relation to the live weight. Carcass quality was assessed by complete dissection into visible lean, fat and bone etc.

2. Of the main effects, energy, supply was without significant effect upon growth, food conversion efficiency (FCE) or any carcass characteristics except body length which was increased with a high energy level. The protein level in the diet had a significant effect upon the percentage of carcass lean and the killing-out percentage, the higher levels of protein increasing both these measurements significantly. Gilts were significantly superior to hogs in every carcass measurement although hogs grew significantly faster.

Yields of varieties of red clover were found to vary from year to year and relative to each other.

Apart from losses in harvesting the seed, which were not studied, yields of seed were found to be correlated with seed set, size of seed and numbers of heads in the crop. In 1958 the dominant factor affecting yields was Kabatiella.

Because of the value of seed set in indicating potential yield, its relation to other characters was studied. Data are given for length of corolla tube, numbers of positive pollinators and size of head as indicated by the number of florets, and their relationship to seed set and to one another.

1. Twenty feeding and digestibility trials were carried out on seven tropical grasses to determine their nutritional value at different stages of growth, and to study their suitability as possible pasture grasses.

2. Content of crude protein was relatively high at immature growth stages of the forages, and declined rapidly with the onset of flowering.

3. Digestibility of dry matter and gross energy increased in most of the forages tested to the 5-week stage of regrowth but declined rapidly in mature stages of forages tested at 6 or 8 weeks of regrowth. Digestibility of crude protein declined with increasing maturity of the forages.

4. The Nutritive Value Index of each forage was highest at four or five weeks of regrowth. The optimum time to graze the forages tested would occur between 4 and 5 weeks of regrowth, at the stage when flowering commences. This would combine high yield of forage with high nutritional value.

Three diets, with silica contents ranging from 0·10–2·84% SiO2 in the dry matter, were fed to sheep and the distribution of silica between the faeces and urine was measured, together with the concentrations of silica in the rumen liquor and the blood. The sum of the amounts of silica excreted in the urine and faeces was within 1% of the amounts ingested. The amounts excreted in the urine increased with increasing silica content of the diet but reached no more than 205 mg. SiO2/day, apparently being limited by the solubility of silica in the rumen. Since the concentration of silica in the blood remained practically constant it is concluded that the silica which enters the blood stream from the alimentary tract passes rapidly into the urine. The amounts of silica excreted in the urine represented small proportions only of the amounts ingested and since the recoveries of silica in the faeces were so nearly complete it is suggested that silica be re-examined as an indicator for digestibility studies.

Investigations have been made of boars yielding spermatozoa with a specific morphological (‘knobbed’) defect of the acrosome.

Counts were made of the number of knobbed spermatozoa in pairs of nigrosin eosin smears made from the semen of normal boars, in the semen of two (‘affected’) full brothers with ejaculates known to contain a high proportion of knobbed spermatozoa, and in mixtures of normal and affected ejaculates. Few or no knobbed spermatozoa were recorded in the semen of normal boars. Virtually all spermatozoa from the affected boars were recorded as knobbed. Counts on mixed samples agreed well with expected values.

1. Thirty Rhodesian soils were cropped with weeping love-grass (Eragrostis curvula) for up to 11 months in the glasshouse, the potassium released on cropping being compared with soil contents and that released on prolonged suspension in dilute CaCl2 or by reaction with H-exchange resin.

2. Love-grass produced up to 33 tons of dry matter and removed up to 700 lb. of K2O/acre, and releases of non-exchangeable potassium ranged from 3 to 2931b. K2O/acre. With some soils potassium uptake by love-grass (and K-release) was about 60% of that reported for perennial rye-grass, showing that different crops have differing abilities to use non-exchangeable potassium reserves.

Fifty Boran Bos indicus steers, all of which were born during the same months, were reared together on grass without supplementary feeding, until required for slaughter. Pre-determined randomly selected groups of these steers were slaughtered at 1½, 2½, 3½, 4, 5 and 5½ years of age. Carcass analyses were carried out and the changing relationship between the edible carcass components themselves and of their relationship to live and carcass weights during growth were investigated. It was observed that certain components maintained a near constant relationship to each other throughout growth. It was also noted that compensatory growth of light-weight weaners enabled them to be as productive, in terms of final carcass weight and composition at 3½ and 4 years, as heavy-weight weaners.