The normal body temperature of the pigs used in these experiments showed an appreciably greater variability than has hitherto been considered normal for pigs, the limits being 98·3–104·80° F. and the variation is independent of environmental temperature, or season of the year. The average normal temperature of the adult hog is 101·7° F.

In fasting for from two to five days a reduction of body temperature was noted in a large majority of cases, amounting on the average to 1·7° F.

Whether the normal or fasting figures are taken, the mean body temperature is higher in youth (50 days) than in the adult hog by about 1·5° F.

Further experiments have been done on the evaporation of water from soil, using the same apparatus and technique as described in an earlier paper. The present series of experiments was designed to investigate the effect of clay content and manurial treatment on the evaporation. Two soils have been used, one containing only 6% clay and the other 15%, and from each soil samples were taken from plots which had received (a) no manure, (b) artificial manure, (c) farmyard manure. The rate at which the soils lost water over concentrated sulphuric acid and at a constant temperature, was found to depend firstly on the amount of clay present, and secondly on the amount of organic material in the soil. The differences due to content of organic material were more obvious in the soil containing the larger amount of clay; the farmyard manure plot lost water at the slowest rate, and the unmanured plot occupied an intermediate position. In the sandy soil the differences in evaporation due to manuring were small.

There is evidence that the moisture equivalent of these soils measures the percentage of water at which the evaporation is first directly affected by the soil particles, and that at percentages of water in excess of the moisture equivalent evaporation is taking place substantially from a free water surface.

Fourteen cow peas were tested for susceptibility to infestation and damage by Callosobruchus maculatus (F.) in the laboratory. IT81D-897 and Popse showed the lowest damage over a 3-month test period. 100-seed weight was not significantly correlated with seed damage.

The developmental period of G. maculatus was significantly longer in IT81D-897 and Popse than in other cow peas tested. Percentage adult emergence and fecundity of females were also lowest in these two cow peas.

The objective of the current study was to estimate heritability and genetic correlations between cystic ovarian disease (COD), foot and leg diseases (FLD) and displaced abomasum (DA) within the first three lactations of Holstein dairy cows. The 57 301 lactation records of dairy cows on 20 large dairy herds in Iran between January 2005 and June 2009 were analysed with three-trait threshold animal models, using Gibbs sampling methodology. The final model included the fixed class effects of herd-year, season of calving, the linear covariate effect of age at calving and additive direct genetic effect of animal. Posterior means of heritability in first, second and third lactations were 0·15, 0·18 and 0·22, respectively, for FLD; 0·09, 0·11, and 0·13 for COD; 0·05, 0·06, and 0·08 for DA. Posterior means of genetic correlations between diseases were low (from 0·03 to 0·14), within lactations; the largest estimates were for FLD and DA, and the lowest involved FLD and COD. Positive genetic correlations between diseases suggest that some general disease resistance factor with a genetic component exists. The results of the present study indicated the importance of health traits for considering in the selection index of Iranian Holstein dairy cows.

Root re-growth, following aluminium (Al) stress, has been used as an indicator of Al stress tolerance. Genetic variation in root re-growth characteristics among eight triticale genotypes was investigated by a diallel analysis. Highly significant variation due to both general combining ability (GCA) effects and specific combining ability (SCA) effects indicated that both additive effects and non-additive effects were important in explaining the genetic variation for Al tolerance. The high estimates of heritability and the predictability ratio for root re-growth revealed the preponderance of additive genetic variance in the inheritance of Al tolerance. Differences in patterns of GCA effects and SCA effects among the parents provided strong evidence that the genetic control of variation for Al tolerance as assessed by root re-growth was a complex polygenic system. Three Al-tolerant genotypes, Tahara, Abacus, and 19th ITSN 70–4, were found to be the best general combiners for larger root re-growth, and they could be used in hybridization programmes to improve Al stress tolerance by following a simple pedigree method of selective breeding.

Maize was grown in the upland areas surrounding an inland valley in central Nigeria in a randomized block experiment using six cultivation techniques (manual cultivation with a hand hoe (MC); ploughing in both directions to throw up a ridge (DPL); single ploughing with the seed placed on the ridge (SPL); ridging with a wooden, single tine, locally made ‘bush’ plough (BPL); single ploughing with the seed placed in the furrow (FPL) and ridging with a conventional ridger (RID) with or without pre-emergence herbicide (PEH) with two replicates. Initial cultivation times ranged from 29 to 70 h/ha (BPL<RID<SPL<FPL<DPL<MC). Total weeding time ranged from 220 to 512 h/ha (MC<DPL<RID<FPL<BPL<SPL) with PEH and from 431 to 763 h/ha (MC<SPL<DPL<RID<FPL<BPL) without PEH. Ox cultivation techniques were associated with higher weeding times and larger weed burdens. Total times for all field operations were 568–758 h/ha (MC<FPL<DPL<BPL<SPL<RID) with PEH and 791–870 h/ha (BPL<MC<SPL<DPL<RID<FPL) without PEH. Thus, although ox cultivation saved time at the most critical time of year (cultivation and planting), it did not save time overall.

Amongst the ox cultivation techniques, work inputs were 6·3–34·1 MJ/ha (BPL<FPL<SPL<RID<DPL) and draught forces 387–1377N (BPL<DPL<FPL<SPL<RID).

Yields of maize cobs were 2·55–4·0 t/ha (SPL<FPL<MC<RID<DPL<BPL) with PEH and 1·65–3·55 (RID<BPL<FPL<DPL<MC<SPL) without PEH. Except for SPL, PEH was associated with increased yield especially when used with ox cultivation.

As regards crop yield, time inputs and work input, there was no advantage to be gained from using a separate (and expensive) ridger for maize compared with a locally made plough or the plough also used for the main cash crop (rice).

At 1992 prices, the cost of PEH was about the same per ha as the price of labour saved on weeding, but additional benefits associated with PEH use were the avoidance of mid-season labour bottlenecks and an overall increase in crop yield.

A trial to investigate possibilities of berry control by cultivation depth is described. Tubers planted at 10 cm produced significantly more potato plants in flower than those planted at 30 cm at the commencement of flowering. However, 3 weeks later the difference in numbers of flowers had disappeared. Emergence of overwintered tubers was about 53%, and of spring-planted tubers about 97%. Depth of planting did not affect emergence. A comparison of overwintered and spring-planted potato tubers showed earlier flowering and berry production by the overwintered tubers of about 1 week on average compared with the spring-planted tubers.

Six chemical treatments were compared at different concentrations and growth stages of potatoes and peas to assess potential control of berry production in potato volunteers growing in a vining pea crop.

Best control was found to be achieved with a combination of 4-(2-methyl-4-chlorophenoxy) butyric acid (MCPB) at 8300 mg a.i./l and Bentazone at 7300 mg a.i./l applied with the potato volunteers at full foliage to flowering stage, and before the pea crop reached the flowering bud stage, or by application of MCPB alone at 8300 mg a.i./l with the potato plants at full foliage to the pre-flowering stage. No chemical treatment either totally destroyed potato foliage, or completely suppressed potato flower and berry production, but it is argued that growers may reduce the effects considerably by careful observation and use of the appropriate chemical at the appropriate time.

Morphophysiological characters, designated as descriptors by the International Union for the Protection of New Varieties of Plants (UPOV) and the International Plant Genetic Resources Institute (IPGRI), and allozyme variation were used to study genetic diversity among four cabbage (Brassica oleracea L. var. capitata L.) open pollinated (OP) populations. The morphological and physiological characters, and gene frequencies among OP populations were analysed by using cluster (CA) and principal component analysis (PCA). Both methods gave the same clustering of OP populations. The relationships found among OP populations by analysing UPOV descriptors (30 characters) and IPGRI descriptors (30+14 characters) were similar. The relationships among OP populations obtained from gene frequencies were not similar to those obtained from morphophysiological characters, but two of the four OP populations were clustered together by both categories of data. The biggest correlation between the relationships among OP populations obtained from morphophysiological characters and those obtained from gene frequencies was r = −0·44 and r =−0·38 given by PCA and CA respectively. The importance of each character or allele with respect to the relationships among OP populations were also detected by PCA.

A Scanning Electron Microscope was used to measure wool fibre diameter, the number of cuticular scale edges, crimp wavelength, the number of shed fibres, and the number of fibre loops in normal and cotted fleeces. The main difference observed was the greater number of loops in the cotted wools. There was no evidence of an increased number of shed fibres in the cotted fleeces.

A urine collection system suitable for male pigs is described. The system was tested by the recovery from urine of an intravenous infusion of51 chromium as the EDTA complex. Recovery from four pigs was 99·2 ± 1·6%.

Twenty-eight Hereford cross Friesian heifer calves aged 3 months were allocated in randomized blocks to two main treatments, namely, ovariectomy (spaying), performed by flank laparotomy, and anabolic steroid oral administration (Ethylestrenol). The cattle were tied in stalls and individually fed ad libitum on a ‘barley-beef’ type cereal mixture until slaughtered weighing approximately 340 kg.

Ovariectomy reduced overall rate of live-weight gain and food conversion efficiency but differences were not significant. Spayed heifers, however, grew significantly taller than entires. Although fat and bone proportions of the side were increased slightly, carcass grading and composition were not appreciably altered by ovariectomy.

Steroid treatment failed to improve performance but lean content of the side was slightly increased. This failure in response may have been due to incorrect dosage.

The production of toxic levels of ethanol in the stomachs of neonatal ruminants resulting from fermentation of glucose by resident yeasts occurs only in the absence of fat from the diet. Daily levels of ethanol and numbers of viable yeast were measured on samples of stomach contents for 21-day periods. Milk fat was shown to control the ethanol production in lambs and calves (but not in vitro in culture), the quantitative nature of this control was demonstrated by experiments with cream using lambs. Nine dietary fats in commercial use homogenized in fat-free milk, a commercial catering ‘milk’, and an intravenous lipid feed were all tested in lamb-feeding experiments, compared with whole and separated milk, and an inert oily hydrocarbon, liquid paraffin.

The determination of dissolved oxygen by Thresh's method may lead to discordant results because of the loss of iodine, which is carried away by the gas passed through the apparatus during the titration.

A modified method is described, which eliminates the above error and obviates the necessity for making separate determinations of the dissolved oxygen of the reagents used.

Correction for the nitrites present in the water can be made by making separate determination by the Griess-Ilosway colorimetric method.

(1) The skeletons of young pigs on a ration composed mainly of cereal grains but with the addition of cod-liver oil show a very distinct lack of calcification, the percentage of ash being about 12 per cent. lower than in the bones of normal animals.

(2) Calcification of the bones proceeds up to maturity. A difference of about 360 gm. tricalcic phosphate was found between the same mature bones of normal and calcium-deficient animals.

(3) The ratio of lime to phosphate is almost the same in the different bones of the same individual as well as in the normal and rachitic bones of swine. The main characteristic of the bones in low-calcium rickets is a low-ash content, but the composition of the ash is normal.

1. Digestibility determinations of broad bran, straight-run middlings and fine middlings are here reported.

2. On the basis of these determinations bran would appear to be a relatively dear feeding stuff for use with poultry, as compared with the finer grades of milling offals.

3. In the case of chick feeding mixtures, the finer milling offals suffer from the disadvantage of causing pasting in the mouth, this disadvantage militating against their too extensive inclusion in chick feeding mixtures. From the evidence obtained in these experiments it would appear that this disadvantage would come into play when more than 40 per cent of the total mixture consists of the finer offals.

4. From the point of view of economy and efficiency of utilization, a mixture of bran and middlings would appear to be of more value than either of these foods fed separately.

5. The inclusion of bran in chick feeding mixtures would appear to be justified on dietetic grounds, in spite of its relatively poor value measured by digestibility trials.

6. From a biological standpoint, bran and bran-weatings mixtures appear to be definitely superior to wheat itself when used exclusively as a source of food and supplemented with 1·5 per cent cod-liver oil and 2 per cent oyster shell.

This study investigated whether the interaction of protein level and grain type can affect milk production, nutrient digestibility and rumen fermentation in primiparous Holstein cows. Four dietary treatments were used: high-protein with barley as the only grain source, HP-B; (2) high-protein with an equal mix of barley and maize, HP-BM; (3) low-protein with barley as the only grain source, LP-B and (4) low-protein with equal proportions of barley and maize, LP-BM. High-protein diets showed no improvement in milk or protein yield compared with low-protein, but barley and maize mix diets increased energy-corrected milk yield and fat yield compared with barley-only diets. The highest total apparent digestibility of dry matter, organic matter and neutral detergent fibre was observed for LP-BM whereas HP-BM showed the greatest crude protein digestibility. Treatment had no effect on total volatile fatty acid concentrations, molar proportion of acetate and propionate and acetate to propionate ratio. The lowest ruminal pH was observed for LP-B. High-protein diets resulted in greater concentrations of ammonia nitrogen (N), urinary N, blood and milk urea nitrogen compared with low-protein diets, whereas low-protein diets showed better nitrogen utilization efficiency. This study showed that primiparous lactating cows do not benefit from high-protein diets with different fermentation rates of grain sources, but barley and maize diets may improve milk production performance, ruminal fermentation and pH under the present dietary conditions. The current results on milk production performance should be interpreted with caution due to the small number of cows used (eight in each treatment).

The F1 and F2 generations of a diallel cross of six-row barley involving the parents, Beecher, Athenais, Atlas 46, 3130-4564-3, and 3130-864-4 were studied and heterosis, inbreeding depression, and combining abilities were measured for grain yield, number of tillers per plant, number of kernels per plant, kernel weight, and plant height. Significant heterosis was detected for grain yield in two of the ten crosses, for number of tillers per plant in one cross, for number of kernels per plant in two crosses, for plant height in three crosses, and for kernel weight in none of the crosses. The inbreeding depression of the F2 generation was present in most cases but significantly so in a few. Atlas 46 x 3130-4564-3 exhibited inbreeding depression for grain yield, number of kernels per plant, and plant height.

The general combining ability (GCA) mean squares of both generations were significant for all characters studied except number of kernels per plant in the F1 generation. The specific combining ability (SCA) mean squares were significant for only plant height in the F1 generation and all characters studied except number of tillers per plant in the F2 generation.

The GCA effects indicated that Beecher and Athenais are good general combiners for grain yield and its components. The latter parent produced good yielding hybrids with slightly shorter plants than the remaining hybrids.

The SCA effects revealed that Athenais × 3130-4564-3, Athenais × 3130-864-4, and Beecher × Atlas 46 seem good specific combinations for high grain yield. Also, the former two crosses tend to produce shorter plants.

The table of results given in the last section shows that for all experiments for which the Resistance Formula has been fitted the values of the constants are consistent, bearing in mind the standard errors to which these values are subject. The constants for nitrogen may be held to have been determined with some approach to precision, but those for potash are not so well determined. We find at Rothamsted, for example, that the crop responds to a moderate dressing of potash, but higher dressings do not usually improve the yields any further. This fact limits the precision of the formula. The reader is asked to refer at this point to the full descriptions as to the meaning to be attached to the constants of the formula given by Bh. Balmukand in the earlier paper(1). The constants an and ak, called the importance factors, are interpreted as determining the capacity of the crop to recover the particular nutrient out of the soil. The chemical analysis of the tubers grown under nitrogen and potash starvation conditions should, therefore, furnish us with values which should be of the same order of magnitude as obtained by the formula. The minimum nitrogen percentage figure is 0·204, which when reduced to our units is equivalent to 4·57 lb. of nitrogen per ton of potato. The values obtained from the Resistance Formula are as close as the standard errors allow us to expect, and are also of the same order of magnitude as the chemical composition of the tubers demands.

An account is given of the relationship between the decrease in pH on incubation of bull semen and fertility. It is shown that, in general, a high pH change tends to be associated with a good conception rate and vice versa. There are, however, exceptions to this general correlation, and it is believed that the pH change test, while giving an indirect measure of sperm metabolism, does not provide the clue to the problem of fertilization.

It is suggested that the covariance method of statistical analysis is of considerable value in correcting for uncontrolled inequalities arising early in an experiment, and in analysing the effects of developmental factors on yield. As an example its application to the results of an experiment with beans is described.

It is with great pleasure that the writers acknowledge their indebtedness to Dr J. Wishart for his helpful criticism throughout the work.