Short columns of air-dry soil crumbs were wetted at different rates and, after draining to a standard suction, the amount of water taken up by each column determined. It was found that this in the other under continuous grass. The extrapolated value of the cohesion of the grassland crumbs at zero rate of wetting was twice that of the arable, indicating an additional cohesive force in the grassland crumbs. The cohesion of the arable soil fell much more rapidly with increased rate of wetting than that of the grassland, probably because the roots in the grassland crumbs provide easy escape passages for the air.

The increase, with rate of wetting, of the amount of water held by a soil sample against a given suction is important, at least up to 200 cm. of water. This dependence of the pF curve on rate of wetting is of particular significance for laboratory studies of water movement in soils.

1. Nitrogen-balance experiments showed that casein supplements fed to hill ewes on a low plane of nutrition in the later stages of pregnancy were used very ineffectively, despite the animals' need for protein.

2. In confirmation of McDonald (1948a, b, 1952) extensive conversion of casein to ammonia was found to occur in the rumen, with absorption of ammonia into the blood stream.

3. Casein administered to sheep by duodenal fistual was better utilized than when administered by ruminal fistula.

4. The course of dissolution in the rumen of casein in the form of tough lumps was observed by a staining procedure.

5. It was found possible to process casein in a way that led to better utilization as shown by nitrogenbalance experiments. This processed casein gave less ammonia in the rumen.

6. It is concluded that the formation in the rumen of ammonia from proteins may be an important factor determining their usefulness to the animal. Processing may have effects on the value of a protein for ruminants quite different from those on the value for non-ruminants. The tendency to value proteins for ruminants solely in terms of their digestibility is criticized, and it is suggested that casein has disadvantages as a ‘standard protein’ in nutrition experiments with ruminants.

1. Herring-meal supplements fed to sheep on a basal diet low in protein were more effective than casein supplements in promoting nitrogen retention and growth.

2. The herring-meal supplements caused less extensive formation of ammonia in the rumen than did the casein supplements. This is considered responsible for the differences found in the value of the proteins.

3. Meat from the sheep fed herring meal was not tainted in flavour.

4. The use of formaldehyde to preserve herring before making them into meal had no deleterious effects when the meal was fed to sheep.

1. Ruminal ammonia concentrations were measured in sheep receiving basal diets of hay and meals with various supplementary sources of protein. Ammonia production from groundnut meal was great and from maize products slight. Herring meal behaved in an intermediate way.

2. The extent of ammonia production from a given amount of protein-rich material was decreased when the amount of starch or cereal meal fed at the same time was increased.

1. The seasonal variation of farm sales of milk was measured for each year from 1937– 8 to 1951– 2 for England and Wales, and for each of the eleven marketing regions into which the country is divided.

2. The effect of changes between years in the amount of seasonal variation in milk values on the amount of seasonal variation in sales was examined and little direct connexion found.

3. Despite the fact that high milk prices in winter do not make production at that time more profitable, farmers get their cows to calve when prices are rising or are at their highest.

4. An inverse correlation was found between the number of calves born alive and sales of milk in the same month, but a positive correlation between the total number of cows in milk and the volume of sales in the same month.

5. That part of seasonal variation in sales which cannot be explained by variations in the number of animals in milk was shown to be mainly due to variations in the shape of lactation curves of animals calving in different months.

6. The importance of feeding, particularly the availability and condition of grass, in affecting the shape of the lactation curve is discussed.

1. Past work on muzzle patterns of individuals and of twins is reviewed.

2. A technique of obtaining muzzle prints by making plaster casts is described.

3. Using casts, muzzle patterns from one-egg and two-egg twin pairs were scored for similarity on a 1– 5 scale. Patterns of one-egg twins were significantly more similar than those of two-egg twins, and the largest part of the total variance was due to the difference between these two groups. The score distributions for monozygous and dizygous twins did not completely overlap, indicating that muzzle pattern is inherited. However, the extent of overlap observed confines the usefulness of muzzle pattern in twin diagnosis to confirmatory evidence at the extremes of the similarity scale.

4. Parts of the muzzle pattern (central groove, cell length, and cell margins) were judged on an arbitrary scale. Two-egg twins were not found sufficiently less similar than one-egg twins for the characters to be useful in diagnosis. Twins were more alike than random pairs, but significantly so only for central groove and MZ cell length.

1. The solubilities of calcium, magnesium and phosphorus in bran, wheat, oats and certain mineral supplements have been determined at pH values between 6·5 and 1·0.

2. The solubility of calcium in calcium carbonate varied with the cereal present, but it was always completely soluble at pH 3·0 and below.

3. The calcium present in bran and wheat was not readily soluble; that in oats was fairly readily soluble.

4. Magnesium dissolved more readily at higher pH values than calcium.

5. Phosphorus in bran (with or without added calcium), and that present as pure salts, was almost completely dissolved at pH 3·0 and below, but very low phosphorus solubilities were found at these pH values in oats and, to a lesser extent, wheat.

6. These results have been considered in relation to the acidification of food which occurs in the true stomach.

1. Tests have been carried out to investigate the hydrolysis of phytate in wheat, bran, and oats.

2. Oats showed practically no phytase activity.

3. Wheat phytase had an optimum pH of 5·0–5·1 and functioned at pH values down to 3·0. When hydrolysis had been arrested by acidifying to pH 2·5 for 5 min. or longer, the phytase did not recover when the pH was raised to 5·0 by the addition of sodium bicarbonate.

4. There was an almost uniform increase in the rate of hydrolysis between 15 and 50° C.

5. The rate of phytate hydrolysis decreased as the reaction proceeded, but the reaction continued until only a very small amount of soluble substrate remained.

6. The presence of calcium, under conditions in which it could form insoluble phytate, reduced phytate hydrolysis to a considerable degree.

7. These reactions are considered in relation to phytate hydrolysis in the digestive tracts of animals.

1. The precipitation of calcium, magnesium, phytate phosphorus, and non-phytate (chiefly phosphate) phosphorus has been determined in ‘hydrolysed’ and ‘unhydrolysed’ bran, with varying amounts of added calcium as calcium carbonate.

2. It was found that calcium phytate was precipitated before non-phytate (chiefly phosphate), whatever level of calcium carbonate was added.

3. Precipitation began and was more complete under more acid conditions when calcium and Ca: P ratio were high.

4. Similar experiments have been carried out using salt solutions containing calcium and phytate, calcium and phosphate, and calcium, phytate, and phosphate. The results were similar in most cases to those of corresponding bran mixtures.

5. The above results have been considered in relation to the precipitations which are likely to occur in the small intestine, and the possible effects of these precipitations on absorption are discussed.

1. The solubility of phytate in the presence of protein has been determined over a pH range 6·5 to 0·5.

2. The fall in solubility of phytate in the region of pH 2·5 is shown to be due to a reaction with protein.

3. The reaction could be reduced considerably by adding calcium.

4. The mechanisms of these reactions are discussed.

A two-row hand-dropping potato planter was modified by adding fertilizer equipment. The machine was used in thirty-three experiments in 1951 and 1952 to plant potatoes from flat land and compare broadcast dressings of granulated compound fertilizer with dressings placed near to the seed.

Fertilizer placed either in one band at the side and below the level of the seed, or in contact with the seed, gave consistently higher yields than broadcast dressings. Broadcast fertilizer gave yields similar to those given by only one-half to two-thirds as much placed fertilizer. On the average of all the experiments, placing fertilizer gave about 1 ton/acre more potatoes than broadcasting. The advantages of placement were greatest when low rates of dressing were used.

Broadcast fertilizer was cultivated deeply into the seed-beds in nineteen experiments in 1952 and gave slightly lower average yields than late dressings broadcast on the seed-beds.

Fertilizer placed in bands on the soil surface immediately in front of the seed-shoes gave yields similar to those given by dressings broadcast over the seed-beds in fourteen experiments in 1951. In average planting conditions fertilizer broadcast on the seed-beds or placed in front of the seed-shoes was thrown to the middle of the ridges and concentrated above the seed.

Fertilizer placed in contact with the seed gave higher average yields than dressings in a sideband at both rates of manuring in the 1951 experiments. In 1952 contact placement was slightly superior to sideband placement at low rates of fertilizer and slightly inferior at high rates. In most experiments in each year emergence was delayed by 10–14 days when the heavy dressing was placed in contact with the seed. Early growth was poor but at most centres the crops recovered later in the season and gave good yields. There is most risk of damage from contact placement on light soils, on badly prepared seed-beds and in dry years. Dressings of 10 to 12 cwt./acre of ordinary-strength compound fertilizers are likely to be quite safe when applied in contact with the seed. If heavier dressings are to be used, part should be applied in contact with the seed and part broadcast, such split applications were satisfactory in experiments in 1951.

Farmers planting even moderate acreages of potatoes by machines will benefit by using a suitable fertilizer attachment. Equipment is needed to place fertilizer at the side of the seed so that heavy dressings can be used to secure maximum yields without risk.

1. Birds fed on rations devoid of animal byproducts from hatching until 18 months of age were equal in laying performance and health to those that had received animal supplements.

2. The stimulation of early growth by feeding aureomycin did not affect the final weight of pullets, their egg production or the incidence of broodiness.

3. The ‘animal protein factor(s)’ was of limited importance for egg production. There was a suggestive indication of an effect of a deficiency of the factor(s) when birds on an all-plant ration had been laying for 6 months without access to their droppings. Limited access to ‘unfermented’ droppings, which provided the only dietary source of the factor(s) during both rearing and laying periods, was sufficient to meet the need of the birds for sustained egg production.

1. Twenty ejaculates were collected from the same boar at weekly intervals; the composition of semen was studied by microscopic and chemical methods. The total volume of ejaculates varied from 240 to 500 ml., and sperm concentration from 50,000 to 177,000 cells/μl. Chemical analysis revealed 2·4–12·6 mg./100ml. fructose, 5·9–23·1 mg./100 ml. ergothioneine, and 32–156 mg./100 ml. citric acid.

2. The sequence with which the different parts of boar semen follow one another at ejaculation was studied by the method of fractionate collection. The earliest to be emitted was the ‘pre-sperm fraction’ from which sperm and seminal vesicle secretion were absent. The next was the ‘sperm-rich fraction’ which showed not only a high sperm content but contained also substantial quantities of substances derived from the seminal vesicles, i.e. fructose, ergothioneine and citric acid. The ‘post-sperm fraction’ consisted mainly of accessory gland secretions.

3. The analysis of semen fractions collected at very brief intervals has shown that whereas the secretion of the seminal vesicles accompanies the spermatozoa at ejaculation, it attains its maximum immediately after the bulk of the sperm has been ejaculated.

1. The construction and performance are described of a simple climatic chamber for work on poultry in hot climates. In addition, brief reference is made to an improved ventilation system and to refrigeration equipment fitted to chambers of later design.

2. Air temperature and humidity may be controlled over a fairly wide range above that of the external air. Radiant temperature is maintained close to air temperature. The air movement averages about 20 ft./min. in the working space.

3. The apparatus is suitable for accurate tests of heat tolerance lasting for a few hours, or for longterm experiments.

4. It is suggested that the provision of climatic chambers for use with farm animals in underdeveloped agricultural areas is not a formidable problem.

The experiment reported here involved thirty-two pigs from birth to bacon weight. During the 9 weeks before weaning sixteen pigs were reared on damp cold floors in a cold building and sixteen were reared on dry cold floors in the same building. After weaning all the floors were kept dry.

Before weaning four out of the sixteen pigs in each treatment died, but only one, which was in the wet cold floor group, was suspected of having a liver disease which has been described by Naftalin & Howie (1949). A greater incidence of this disease was expected to occur under the cold environmental conditions of the experiment.

After weaning one deformed pig was killed and three other pigs were killed at 40 weeks old. The latter three all had the liver disease. There was evidence that the disease had developed after the pigs were weaned and this indicated that it cannot necessarily be prevented by the provision of dry conditions in a cold house. The growth curves of two of the three pigs fitted the hypothesis that the disease is associated with cold environmental conditions, but the growth curve of the third suggested that it might have contracted the disease during the summer when the minimum air temperature was 54° F.

The possibility was discussed that the liver disease is caused by a virus or low nutritional status interacting with the effects of cold environmental conditions.

The two pre-weaning treatments had no dissimilar effects upon the piglets' weaning weights, blood haemoglobin levels and appetites for solid food, nor did they have any differential effect upon the growth rates and efficiencies of conversion of food to flesh of the pigs which survived to bacon weight. The bacon carcasses from the pigs born and reared to weaning on wet cold floors were shorter and fatter than those from pigs born and reared on dry cold floors. No explanation could be offered for this difference in carcass conformation.

The rates of heat loss from a constant temperature water-bath to an uninsulated concrete floor upon which pigs had not lain were halved by the provision of ½ in. depth of chopped straw bedding. They were also halved if the measurements were taken after pigs had recently been lying on the bare floor, and under these circumstances the provision of ½ in. depth of chopped straw bedding cut the heat losses even further.