1. The jaw movements of four sheep were recorded while they were consuming a daily diet consisting of a constant concentrate allowance along with a hay intake varying from 25 or 50 g. daily by daily differences of 25 or 50 g. up to maximum voluntary intake.

2. Rumination increased with hay intake in a characteristic way. The actual time devoted to chewing when plotted against hay intake produced a curve consisting of a rapid rise, a fairly level part, a further gradual rise and a final levelling-off. This was less clear when the total rumination time or the total number of regurgitations were compared to the hay eaten.

1. The effects on forage yields as a result of the interaction between fertilizer management and stage of harvesting an oat companion crop were studied under the climatic conditions of northern Ontario.

2. Grain yields as well as silage yields were increased on the application of 400 lb. 4–24–12 per acre. Fertilization of the corffipanion crop seeded with a- hay mixture resulted in first- and secondyear yields that were significantly greater than those obtained without fertilization of the companion crop.

3. By harvesting oats at the silage stage rather than as mature grain only the succeeding firstyear hay yields were significantly greater on the application of additional phosphorus and potassium.

1. The paper describes ten consecutive field experiments carried out between 1952 and 1961 investigating the action of F.Y.M. on the yield of maincrop potatoes. In all experiments high basal dressings of PK fertilizer were used.

2. Soil moisture deficits were estimated from meteorological data and the maximum deficit (M.S.M.D.) in a particular season used as an index of the dryness of the growing season.

The total amount of pollen collected by colonies taken to crops of sweet cherry, field beans and red clover was greatly increased by feeding syrup to the colonies. Hence feeding colonies with sugar syrup increases their pollinating value.

Castration of males is a long-established practice in animal husbandry, and although the use of boars rather than hogs was advocated by Fitzherbert in 1534 the use of castrates in pig production has continued to the present day.

1. Two identical small plot experiments were done from 1961 to 1963, at the Hannah Dairy Research Institute, Ayr and at Boghall Farm, Midlothian to study the effects of applying nitrogen fertilizer at different times on total yield and its seasonal distribution.

2. Two perennial rye-grass plus white clover swards, one containing S23 and the other S24, were used at each site. On both swards a total of 10 cwt. of ‘Nitro-Chalk’ (15·5% N)/acre, applied at varying dates over the growing season, and a control treatment which received no nitrogen fertilizer were tested.

1. In an experiment conducted at the Hannah Institute the effects of irrigation and fertilizer nitrogen treatments on four sward types were studied for 3 years. The swards were S 23 perennial rye-grass with S 100 white clover, S 23 rye-grass alone, S 37 cocksfoot with S 100 white clover, and S 37 cocksfoot alone.

2. The irrigation treatments were—a control (no water) treatment, and two treatments which were irrigated to planned deficit levels of 2 or 0·5 in. below field capacity.

1. Agricultural crops can be grown to maturity with their root systems and associated soil sealed into 1680 1. respirometers. The crops appeared to grow normally and produced the expected agricultural yields.

2. The mean daily oxygen consumption at maturity of the roots of the following crops grown at normal agricultural spacings were: potatoes 2·8 l./m2, marrowstem kale 5·6 l./m2 and tobacco 3·0 l./m2.

The extent of mineralization of organic carbon (carbon dioxide production) during incubation at 28° C. of a sandy loam was determined (a) over 6–12 weeks at varying static moisture levels over the range from air-dried to waterlogged, (b) over a second 6-week period after changing soil moisture level, maintained at various moisture levels during the first 6-week period, to 50% saturation or to waterlogging.

1. Two perennial grasses, rye-grass S24 and cocksfoot S37 have been sampled at 7 to 10-day intervals from the stage of growth just prior to flower emergence to seed shedding. Each sample was separated into leaf, leaf sheath, stem and head (where present) and the fractions examined histologically for lignin formation and chemically for lignin and nitrogen percentages. The in vitro digestibility of most of these fractions was also determined.

1. A radio-telemetric system linked to a thermistor- probe embedded in deep muscular tissue has been used to record continuously variations in deep-body temperature during 46–66 hr. in three Hereford (temperate) and three East African zebu (tropical) cows under similar temperate field conditions.

2. The limitations of the ‘probe’ technique for measuring deep-body temperature are discussed.

Italian rye-grass was grown in the greenhouse in clay loam soil in winter 1962 with several rates of a nutrient solution containing NO3-N and P, K, Ca and Mg to see whether the grass had maximum values for sums of the cations and anions (σ cations, σ anions). Two other experiments were done in summer 1962 with a similar nutrient solution containing either NO3-N alone or NO3-N plus NH4-N.

At the same level of added nutrients summer yields of grass were about twice those in winter and there was little difference when nutrient mixtures with NO3-N+NH4-N or with NO3-N alone were used. The sum of the cations (m-equiv./lOO g. dry matter) in the grass was positively correlated

This study deals with the first 2 years of grazing trials on improved pastures of tropical grasses and legumes at Ibadan in Nigeria. The mixtures consisted of (i) Cynodon plectostachyus and Centrosema pubescens (legume), (ii) (i)+Chloris gayana and Digitaria decumbens, (iii) (ii) +Stylosanthes gracilis (legume). The mixtures were sown and planted in four blocks, the treatments being repeated four times, and were grazed rotationally by N'Dama cattle. During the first year's trial a uniform stocking rate of 1·7 steers/acre was adopted and a recovery period of 11 weeks was allowed. In the second year's trial the stocking rate was increased to 2·7 beasts/acre by the addition of nine yearling heifers and the recovery period was reduced to 5 weeks. Herbage yield and intake were measured by the clipping technique.

1. The effect of four different planes of nutrition of lambs until they reach 30 1b. dressed carcass weight on the development of the form of the ribs is studied.

2. The growth in length of the ribs is found to be more influenced by age and less by the plane of nutrition than their growth in thickness, and is not reflected in the weight of the ribs.

1. The levels of blood reducing sugars, haemoglobin, protein N, NPN, ammonia N, and urea N in addition to the nitrogen retention and digestibility coefficients of food constituents, were studied in lambs with and without ciliate protozoa.

2. The inoculated lambs have higher blood haemoglobin, protein N, and lower reducing sugars, ammonia N, and urea N values than those of the uninoculated lambs.

In a replicated trial the high resistance to bacterial blight of the Allen derivatives Reba W296 and Albar strains was confirmed. Only one major gene, Lagière's B9, was detected in Reba W 296. The very high resistance of this variety is due to B9 fortified by genes of small effect.

The key to resistance in Albar derivatives is the major gene B2: the presence of B3 awaits confirmation. It was found that Albar 49, maintained in Uganda, had deteriorated in resistance to leaf infection in the Sudan. Possible reasons for this change are discussed. All Albar derivatives selected in East Africa for stem and boll resistance were found to be variable for leaf resistance under Sudan conditions.

1. Blood plasma of normal fed sheep is not pigmented but on starvation the plasma assumes a yellow to green colour. Unlike the pigments of the so-called yellow fatted sheep, the pigmentation disappears on refeeding.

2. Using spectrophotometric and chromatographic methods, this pigment has been identified as xanthophyll (lutein).

3. The xanthophyll content of plasma is related to the plasma non-esterified fatty acid (N.E.F.A.) concentration and it therefore appears that the pigment is mobilized from the fat depots together with the free fatty acids. Maximum levels of about 60μg./100 ml. xanthophyll are observed in sheep plasma after 4 days starvation.

1. Fifteen male Merino lambs suckling the ewe and four adult Merino wethers were fed the same pelletted diet. The lambs had free access to milk from the ewe and were creep-fed the pelletted diet. Feed intake by each lamb was measured daily.

2. The digestibility of the dry matter of the pelletted diet was determined in a conventional total collection trial with the adult wethers. Dry-matter and crude-protein digestibility "was determined in the lambs on faeces taken at, or just before, slaughter by the lignin-ratio method.

1. It has proved possible to operate a ‘worm-free’ area in which sheep grazing experiments can be carried out, without significant interference from disease.

2. The organization of such a unit is described and the results are presented in terms of the problems and difficulties which have been encountered during 4 years of continuous and increasing use. There is no apparent reason why these problems should increase with time.