1. A 23 factorial with a split-plot allocation of treatments was used to investigate the effects of silage type, (sweet v. grain sorghum); level of urea, (60ν. 120 g. per head per day); vitamin A,(0ν. 40,000 i.u. per head per day), and intraruminal cobalt oxide pellet on the performance of steers fed rations of 90% sorghum grain, 10% sorghum silage.

1. A group of six lactating ewes, rotationally grazed a low-nitrogen treated plot (40 lb nitrogen applied in early March) and a similar group a highnitrogen treated plot (1001b nitrogen applied in early March and 60 lb at monthly intervals thereafter, all as Nitro-chalk) from mid-April to early July, and the concentrations of serum magnesium and calcium along with food intake and milk yields of the ewes were studied.

Barley, wheat and oats were grown in field and in glasshouse-pot experiments without fertilizer-N, and with added ammonium sulphate or calcium nitrate. In the field fertilizers supplied 50 and 100 lb N/acre, in the glasshouse 100 and 200 lb N/acre (calculated from the surface area of the pots). Plant samples were removed at various stages, dry weights were measured, percentage N determined and N uptake calculated. Those taken after the ears had emerged were divided into ear and straw. The number of coleoptiles emerging and of ears in the later samples were counted. Soil samples were taken after removing the plants grown in the glasshouse, and analysed for ammonium and nitrate.

1. Herbage harvested from 17 April to 3 July, at approximately 3 weeks after defoliation, from a succession of high-nitrogen paddocks (1001b. nitrogen in March and 60 lb. nitrogen at monthly intervals thereafter, all as Nitro-chalk) and from corresponding low-nitrogen paddocks (40 lb. nitrogen as Nitro-chalk in early March only) was fed to two wethers, and the availability of magnesium and calcium were measured in a series of balance trials.

1. Cereal plant density affects yield and growth parameters of fundamental importance. An experiment is described in which growth and development, and yield and yield components of barley grown over a wide range of density were examined.

2. Four varieties of barley—Proctor, Plumage-Archer, Domen, and Moore—were grown at densities approximately equivalent to 35, 70, 140 and 280 lb/acre. Density was found not to affect seedling establishment or plant survival, but there was a variety effect on seedling establishment.

3. Varietal differences were seen in maximum tiller number, and the percentage of tillers surviving to form ears. These differences were most marked between the six-row variety and two-row varieties. The effect of increasing density was to increase the maximum tiller number, but this was followed by different rates of tiller death until early June, after which there was no further compensation for tiller number. Ear emergence and ear number were affected both by variety and density.

1. An experiment was conducted in which lambs grazed on pastures of cocksfoot, ryegrass and tall fescue grown with and without white clover, as well as on pastures of pure white clover.

1. Six heifers were used in eight experiments to determine the digestibility of cacao-pod meal when fed in all-ground mixes of rice bran and rice bran with cottonseed meal.

Analyses of yields for 12 sets of test-crosses of inbred lines of winter beans are given.

A co-ordinated trial has been carried out at eighteen centres to compare the following amounts and methods of providing water to growing pigs: (1) water in the feed in the ratio of 2½: 1; (2) water in the feed in the ratio of 4:1; (3) dry feeding with water available separately ad lib.; (4) water in the feed in the ratio of 1½: 1 and also available separately ad lib.

Pigs on dry feeding had substantially worse growth rate and feed conversion; carcass lengths were slightly smaller and eye muscles slightly wider. Fat measurements were not significantly affected.

1. Perennial ryegrass (S. 23 and S. 24 sown together) and cocksfoot (S. 37 and S. 143 sown together) were compared in grazing and individual feeding experiments during the summer months of 1960, 1961 and 1962, using spring-born calves.

2. Herbage samples indicated that more grass was available to the animals grazing on ryegrass than on cocksfoot in 1961 but no differences were found in 1962. The ad lib. method of feeding should have ensured that quantity did not affect the results in the feeding experiments.

1. A modified capacitance meter used to make rapid non-destructive measurements of growingpasture is briefly described.

Carcass weight, bone weight, bone length, and bone weight per unit length were examined as possible indices of the weight of muscular tissue in lamb and mutton carcasses.

The gas production in batch fermentation of vegetable matter found on farms is shown to lend itself to the application of monomolecular equations providing an active and well-developed starter material is used for initiating the fermentations. The reaction velocity constants as established for a common material found in the tropics, namely elephant grass, would seem to be some two to five times lower than that previously reported for sewage sludge. The higher rate of decomposition of the sewage sludge is attributed to its more favourable physical condition and possibly also to its greater content of more easily fermentable substances.

1. The effects of CCC, (2-chloroethyl)-trimethyl ammonium chloride, on the grain yields of wheat and barley in Britain were studied in field experiments in 1964 and 1965.

The data from 555 normal pregnancies during a period of 6 years in a flock of Scottish Half bred ewes were examined for relationships between gestation length and litter size, birth weight, sex, and age of ewe. A' comparison of Scottish Half bred gestation lengths was also made with those of Specklefaced Welsh ewes.

1. Fifty-one Scottish Blackface ewes were divided into three groups and individually fed throughout the latter half of pregnancy: (I) in excess of nutrient requirements, (II) to produce a uniformly moderate degree of undernourishment during the last 6 weeks of pregnancy, and (III) to produce a uniformly severe degree of undernourishment during the last 6 weeks of pregnancy,

2. The prescribed levels of undernourishment were maintained by weekly adjustments of feed intake based on plasma FFA levels (group II) and plasma ketone levels (group III). The use of the technique is discussed.

3. Undernourishment during the latter half of pregnancy reduced birth weights of single and twin lambs after adjustment for weight of the dams to the same extent. In the moderately undernourished ewes the reduction was approximately 10%, and, in the severely undernourished ewes, approximately 25%.

The absorption of 28Mg from the gastro-intestinal tract of sheep has been measured on both hay and spring grass diets, each of which supplied approximately the same amount of magnesium daily. A hypomagnesaemic response to the latter diet was accompanied by a reduction in the efficiency of magnesium absorption and was not merely due to the presence of bound magnesium in spring grass.

1. A large direct calorimeter in the form of a pig: pen, with sleeping and dunging areas, is described. Groups of pigs can live in it for the whole fattening period, while sensible and evaporative heat lossesare measured continuously.

1. Observations were made on the casting, or accidental immobilization in dorsal recumbency, of Dorset Horn ewes under grazing conditions for a 12-month period.

Magnesium deficiency symptoms in sugar beet have increased recently. Seventeen factorial fertilizer trials, on fields where magnesium deficiency was expected, gave a mean response of 3.7 cwt/ acre of sugar to 5 cwt/acre of kieserite. Magnesium slightly increased the yield of tops, and either did not affect, or improved, juice purity and sugar percentage; it decreased yield on only one field.