1. Twenty-four sampling units from 50 fields of differing soil type and past manurial history have been examined separately for pH and 1% citric soluble phosphorus and potassium to determine the errors which can occur in obtaining a representative sample for analysis.

2. Soils which had received lime and fertilizers within 3 years of the sampling date showed appreciably greater sampling errors than those which had not.

3. The sampling errors were greater than the analytical errors and were such that the common practice of classifying soils into six fertility groups was not justified. Three major groups are more reasonable and practical for routine advisory purposes.

Three hundred and eighty-two Fayomi pullets were available from different hatches throughout the year. The age and body weight, as well as the weight of first eggs at sexual maturity in relation to growth curves, were recorded. The fertilizability and hatchability of the first eggs laid at sexual maturity were also examined from one hundred pullets hatched during the months of November and August.

1. (a) The winter hatches (December, January and February) reached sexual maturity at 183 days and at a body weight of 1093 g. The weight of the first ten eggs was 31·8 g., while the period from first to the tenth egg was 26 days. Summer hatches (June, July and August) reached sexual maturity at 165 days and at a body weight of 1124 g., while the weight of the first ten eggs was 32·4 g. and the period from first to tenth egg was 31 days. Autumn hatches (September, October and November) reached sexual maturity at 159 days and at a body weight of 1023 g., while the weight of the first ten eggs was 31·4 g. and the period from first to tenth egg was 23 days.

(b) Summer and winter hatches attained sexual maturity at an older age and heavier body weight, and laid heavier first ten eggs in a longer period than autumn hatches.

2. The growth curves were higher for the summer hatches than for the spring (March, April and May) ones. Winter and autumn hatches were intermediate. Summer hatches attained sexual maturity at a higher relative growth rate than autumn and winter hatches. In Egypt (30° N.), the effect of temperature seems to override that of daylength in respect to growth and sexual maturity.

3. Yearly differences in the attainment of sexual maturity were significant, mainly in December hatches. Individual differences were minimized during summer hatches.

4. (a) The first egg laid can be fertilizable and even hatchable. When sexual maturity was attained at an old age or a heavy body weight, the first eggs laid had a greater chance of being fertilizable and hatchable. This is due to the weight of first eggs laid and to the season at which sexual maturity is attained.

(b) The attainment of sexual maturity as measured by the fertilizability and hatchability of first eggs, seems to be a gradual phenomenon.

The structure, distribution and dimensions of skin strata and sweat glands have been investigated in Egyptian buffaloes and cattle. Samples from sixteen body regions were taken from three adult bulls of both species. Identical studies were also made on one buffalo calf and two buffalo embryos. Serial vertical and horizontal sections were cut from each body region using the ‘terpineol paraffin wax’ method. The following results were obtained.

1. Buffalo skin is characterized by dermal papillae enclosing papillomatous epidermis. The fibrous structure of the dermis is similar in both species. In buffaloes, the average thickness of skin, main epidermis, papillomatous epidermis, and cornium is 6·5 mm., 50, 115, and 11μ respectively. The epidermis coefficient is 12 for the main epidermis and 18 for the papillomatous epidermis. In cattle, the average thickness of skin, epidermis and cornium layer is 4·3 mm., 51 and 5 μ respectively, while the epidermis coefficient is 8.

2. The average number of hair follicles per sq.cm. of skin is 394 in the buffalo and 2633 in cattle. Each hair follicle is accompanied by two large lobulated sebaceous glands in the buffalo, and one small bilobed gland in cattle.

3. There is no species difference in the histology of the sweat glands. Each hair follicle is accompanied by one sweat gland in both species. In the buffalo, the body of the sweat gland is oval and convoluted, while the duct is twisted at its attachment to the body. In cattle, the body of the gland is elongated while the duct is straight. The number of sweat glands per sq.cm. of skin is 394 in the buffalo and 2633 in cattle. The dimensions of the sweat glands are larger in buffaloes than in cattle. The length, circumference and sweating surface of the gland is 0·58, 0·47, and 0·276 sq.mm. in the buffalo, and 0·47, 0·26, and 0·124 sq.mm. in cattle respectively. The glandular surface of sweat glands per sq.cm. of skin is 1·07 sq.cm. in the buffalo and 3·08 sq.cm. in cattle.

4. The type of sweat gland secretion is apocrine in both species. In the buffalo, successive stages of apocrine secretion are observed, and the merocrinelike form is rare. In cattle, the merocrine-like form prevails and the other stages are very rare. The theory (Findlay & Yang, 1950) of intraluminal transformation, of secretory products from coarse granularity to fluid homogeneity is supported. The effect of locality on the type of sweating activity is stressed.

5. There are species differences in the distribution of blood vessels and capillaries. In the subepidermal level, the arterial branches are more frequent and superficial in buffaloes than in cattle. Capillaries are found in the dermal papillae of buffalo skin. The capillary loops encircling the hair follicle are more frequent in cattle than in buffaloes. The blood capillaries supplying the sebaceous glands are more numerous in the buffalo than in cattle. The blood supply of sweat glands is poor in both species.

6. There are age differences in the skin histology. The number of hair follicles per sq.cm. of skin in a 5-months-old embryo, calf at birth, and adult buffaloes is 10560, 1248 and 400 respectively. There are no skin glands in the 1-month and 5-months-old embryos. The sweat gland in the calf is small in size and similar in structure to that of the adult. Calves have fewer sweat glands than adults.

7. The body conformation and the degree of pigmentation are affected by species, breed and locality.

8. The secreting activity of the sweat glands may be affected by the locality.

9. It seems that there are species differences in the mechanism of heat convection and radiation, insensible perspiration and sensible perspiration, due to histological differences.

1. Three experiments are described in which the value of electrically warmed floors for fattening pigs, aged 9 weeks or more at the start of the trials, was determined.

2. Under the conditions of the experiments, no benefit was obtained either in live-weight gain or efficiency of food utilization by the provision of artificial floor warming.

3. Data relating to the effect on floor surface temperatures of ambient inside temperature, electrical warming, provision of straw and the pigs themselves were presented.

1. A total of forty-two Suffolk cross-bred and 230 stud Romney Marsh ewes were used in four experiments in which pregnant mare serum gonadotrophin (p.m.s.) was used in various combinations with progesterone and oestrogen in attempts to induce fertile mating in anoestrus.

2. Groups of six Suffolk cross-bred ewes were injected with 1000 i.u. p.m.s. after pretreatment, commencing 4 days earlier, with 75 mg. progesterone administered in one of four different ways. Six twice-daily injections in oil resulted in oestrus in five ewes in each of two groups treated. Single injections in oil solution, aqueous suspension, and benzyl alcohol emulsion resulted in oestrus in two, nil, and four ewes, respectively. All were served within 48 hr. of injection of p.m.s.

3. Ovulation was observed in five of six crossbred ewes which received six twice-daily injections of progesterone in oil, without subsequent injection of p.m.s. Three were served.

4. Divided injections of progesterone commencing 4 days before 750–1000 i.u. p.m.s. failed to induce a satisfactory oestrous response in Romney Marsh ewes. An increase to 7 days in the duration of progesterone stimulation resulted in oestrus in all of eighteen ewes treated.

5. The injection of a benzyl alcohol emulsion containing 75 or 150 mg. progesterone, given as a single dose 4 or 7 days before 750 i.u. p.m.s., failed to induce a satisfactory oestrous response. Of seventy-two ewes treated, only seven were served.

6. Lambing results were most unsatisfactory when progesterone-p.m.s. treatment was followed by artificial insemination. Of 144 Romneys inseminated, only twelve lambed. Successful pregnancy appeared unrelated to the type of treatment or the occurrence of oestrus.

7. On the basis of the oestrous responses observed after the injection of a variety of combinations of oestrogen, progesterone, and p.m.s., and by reference to quantitative data on progesterone-oestrogen relationships in oestrous behaviour in the spayed ewe, it is concluded that the developing follicle of the Romney Marsh ewe produces an amount of oestrogen approximately equivalent, in its physiological activity, to a single injection in oil of about 20 μg. oestradiol benzoate.

1. A 24 factorial experiment involving 68,713 first inseminations was carried out at four artificial insemination centres, to compare semen diluents containing citrate or phosphate buffers and all combinations of sulphanilamide, streptomycin and penicillin.

2. The analysis of the results was carried out on punched card machines and on an automatic calculator (EDSAC), as well as on bench machines.

3. The main results obtained were:

(i) Unsupplemented phosphate buffer gave a conception rate 5·5% above that obtained with unsupplemented citrate buffer.

(ii) Citrate buffer with sulphanilamide, streptomycin and penicillin gave a conception rate 6·8% above that obtained with unsupplemented citrate buffer; and

(iii) Phosphate buffer with penicillin gave a conception rate 9·3% above that obtained with unsupplemented citrate buffer. This effect was not, however, significantly greater than that referred to in (ii).

4. Phosphate buffer depressed conception rate when used with sulphanilamide or streptomycin.

1. The rates of growth and efficiencies of food conversion between 45 and 100 lb. live weight of pigs kept to a low plane of feeding were most adversely affected during the winter months by bad housing conditions, wherein the average air temperature was 43° F. On the other hand, this bad housing had no adverse effect upon pigs of a similar size kept to a high plane of feeding.

2. The summer season, with consequently higher environmental temperatures in both good and bad piggeries, only had a significantly beneficial effect upon the rates and efficiencies of growth of pigs of 45–100 lb. live weight kept to a low plane of feeding in a bad piggery. Any effects upon the growth of pigs of similar size kept to a high plane of feeding in either a good or bad piggery or to a low plane of feeding in a good piggery did not approach statistical significance.

3. There was probably some environmental factor other than air temperature or relative humidity which had a beneficial effect on the growth of the pigs kept to a low plane of feeding in the good piggery.

4. It was observed, but not proved, that pigs of 100–200 lb. live weight kept to a high plane of feeding grew rather more efficiently in the bad house than in the good house, despite the higher environmental temperatures in the good house.

5. During the growth period between 45 and 100 lb. live weight the efficiency of food conversion, expressed in pounds t.d.n. required per pound liveweight increase, was better in the well-housed pigs kept to the low plane of feeding than in the highplane pigs housed in either piggery.

6. During the growth period between 100 and 200 lb. live weight the efficiency of food conversion of the well-housed low-plane pigs was significantly better than that for the well-housed high-plane pigs, but was not significantly better than the efficiency of food conversion of the high-plane pigs from the bad piggery.

1. Methods, buildings and equipment used for milk production in Caernarvonshire, Hertfordshire, Pembrokeshire and Wiltshire have been ascertained by a random sample survey carried out in 1948–9.

2. The results showed marked differences between counties in practically every respect which are summarized in thirty-two tables.

3. The value of this survey and some points in its planning and execution are critically discussed.

Data concerning a random sample of about 4% of the flocks in Yorkshire were collected in the form of answers to a questionnaire. The information required was given by 98% of the farmers in the sample.

The survey has shown the extent of losses associated with pregnancy and parturition in 1952–3 and the areas in which they were most severe; it has also given some indication of the factors that might be affecting losses of different kinds.

In addition to this information, the survey has provided statistics concerning feeding and husbandry and the relative importance of different breed types in Yorkshire.

1. A review of the literature relating to the frequency at which pigs suckle under natural conditions was made. The evidence indicated that the average interval between successive sucklings is approximately 1–1¼ hr.

2. A number of sows and their litters were continuously observed for varying periods of time under natural conditions and a similar average interval between sucklings was observed.

3. A review of the literature relating to the determination of milk production of sows was made. This showed that the majority of previous workers imposed, during the periods when the litters were being weighed before and after every suckling, a suckling frequency that did not simulate the natural behaviour of the animals. Evidence suggesting that the imposition of such unnatural conditions invalidated the findings, in so far as they might indicate the true milking capacity of the animals, was discussed.

4. An experiment to obtain direct evidence on the importance of the suckling interval in relation to the milk obtained by the pigs was carried out. Conclusive evidence was obtained that when suckling was allowed every hour, both the quantity of milk obtained by the litters and their live-weight gain in 24 hr. periods were much greater than was the case when suckling was allowed only every 2½ or 3 hr. In addition, the pigs on the hourly suckling frequency utilized their milk intake more efficiently.

5. An experiment was carried out in which an attempt was made to obtain, under natural conditions, a valid estimate of the 56 days' lactation yield of three Large White gilts. The method of weighing the individual pigs before and after suckling was used, and the animals were allowed to suckle every hour.

6. The estimated average lactation yield was 768 lb., with a range of from 882 to 655 lb., although it was suggested that the true yield might be some 5–10% higher. The figures obtained in this work were shown to be very much higher than the yields reported by most of the previous workers.

7. The nursing and suckling behaviour of the dams and their litters was studied. Observations of significance in relation to the variation in growth of pigs within a litter were made.

8. Data were obtained concerning the average amount of milk obtained by individual pigs at a suckling, the total amount ejected at a suckling, the effect of daylight and of darkness on the amount of milk obtained, the relative productivity of the individual mammary glands and the efficiency with which the milk intake was utilized by the individual pigs in the litter.

9. A close positive relation between milk intake and live-weight gain during the first 3 weeks of life was found. During the last 5 weeks of lactation, when supplementary food was available, this close relationship was not seen.

10. The growth rate of the suckling pig, as related to the supply of food, was discussed. The evidence available suggested that the supply of sow's milk was frequently insufficient to meet the requirements of the pigs for optimum growth.

11. The chemical composition of sow's milk in relation to the stage of lactation was studied.

1. The digestibility of the carbohydrates in barley, wheat and maize has been determined, using both conventional methods and individual methods for sugar, starch, pentosan, cellulose and lignin.

2. Sugar and starch were completely digested; cellulose and lignin were indigestible and the pentosan was about one-third digested.

3. Digestible pentosan accounted for about 3% of the total digestible carbohydrate.

4. The ratios of the available carbohydrate, i.e. the total of sugar plus starch expressed as starch, was almost exactly the same as that of the digestible carbohydrate and could be used as a measure of the relative amounts of digestible carbohydrate in the foods.

In continuation of a series of studies on the habits of Zebu cattle, records for the quantities of water consumed every hour by ten cattle during twenty periods of 24 hr. observations have been analysed.

A large variation in day-to-day consumption was evident, but water was taken on an average during 8 hr. of the day with only a small amount of water consumed during darkness. The mean consumption per animal per 24 hr. period was 9·04 kg. (1·9 gal.). The range was 5·1–12·7 kg. (1·1–2·8 gal.).

The water consumption records were subdivided into those days on which water was drunk during a small number of hours and those days when water was drunk during many hours. Although the hourly consumption differed markedly the end result showed a similar intake.

A significant negative relationship was found between water consumed and grazing counts, and for one group a significant positive correlation was found between water consumption and dry air temperature.