Carcasses of 129 steers from ten different sire breeds including dairy breeds, traditional British beef breeds and continental breeds were classified according to the shape of the tuber ischii-tuber calcis profiles of their hindquarter using a 7·point conformation scale. Conformation class was found to be related to both commercial and dissected carcass composition as well as the dimensions of seven hindquarter muscles. At the same carcass weight and fatness the muscle content of the hindquarter increased by 0·56 kg and the bone decreased by 0·13 kg linearly per unit increase in conformation class; the corresponding increase in the muscle-to-bone ratio was 0·07. The general trend for muscle dimensions was that the convex carcasses had shorter and thicker muscles than concave carcasses. A simple method of assessing carcass conformation based on three fundamental profiles of the hindquarter, from which the seven conformation classes were derived, permitted the grouping of carcasses according to their composition. Nevertheless the accuracy of the method may be improved with further investigation.

The paper reports a laboratory study on miscible displacement of reactive solutes during leaching a highly saline-sodic soil rich in soluble sodium carbonate with solutions of calcium chloride. The effect of varying flow velocities, initial soil moisture content and concentration of calcium in the leaching water on the extent of carbonate precipitation and replacement of sodium by calcium from the exchange positions was studied in soil columns. The results showed that precipitation of soluble carbonates in the soil increased with increasing flow velocity, initial soil moisture content and concentration of calcium in the leaching solution. The results further showed that the calcium exchange capacity of the soil was reduced significantly and nearly proportionally with decrease in the degree of water saturation as a consequence of decreased water application rate and initial soil moisture content. In view of the results obtained, a simple model to describe calcium-sodium exchange under unsaturated flow conditions in saline-sodic soils under consideration has been proposed. Possible implications of the results in actual field situations is discussed.

Two experiments were made, each with 35 autumn-calving cows fed on complete diets containing 40–70% hay and 60–30% concentrates. In both experiments, cows fed to appetite on a diet containing 11 MJ metabolizable energy/kg D.M. for weeks 7–24 of lactation ate about 20% more than cows rationed according to yield, but produced only about 3% more milk. The cows fed to appetite gained more in live weight, but lost their weight advantage during the subsequent grazing season.

In Expt 1, a further group of cows were fed to appetite on diets progressively reduced in metabolizable energy content from 11·0 to 9·2 MJ/kg. Dry-matter intake decreased by about 1·2 kg/day per 1 MJ reduction in energy content. The lower dry-matter and energy intakes of cows on this treatment did not significantly reduce their milk yield, but their response when turned out to grass suggested under-nutrition in late winter. In Expt 2, increasing the energy content of the diet in early lactation (weeks 7–12) and reducing it thereafter had no significant effect on milk yield.

Within each treatment group there were reasonably close relationships between energy intake and energy requirement. Nevertheless, it seems likely that the efficiency of feed utilization of cows fed on complete diets will be low unless intake is controlled by energy dilution.

Urea is not efficiently utilized by ruminants mainly because of its more rapid (about 4 times) rate of hydrolysis than the corresponding uptake of ammonia by the rumen microbes (Bloomfield, Garner & Muhrer, 1960). A number of attempts have been made to slow down the release of ammonia either through the production of urease immunity (Sidhu, Jones & Tillman, 1968) or by complexing urea with starch (Deyoe et al. 1968) or with molasses (Chopra et al. 1974). The present communication reports the method of preparation and in vitro breakdown of urea-hemicellulose complex.

In two field experiments with winter wheat varieties, the grain yields per unit area calculated from entire plots 4·2 × 1·18 m were 25% greater than the yields of the centre row. This occurred mainly because the outer rows in the plots yielded 62% more than the centre row. When the yields were calculated on the basis of a plot width of 1·53 m (the distance from path centre to path centre across the long axis of a plot), it was estimated that they were 4% less than the yields of the centre rows. In the most extreme case when a short variety in a plot of this size was bordered by neighbours 70 cm taller, its yield, relative to that of the tall variety, was underestimated by 10–12%.

A separate experiment showed that the greater yield from plants at the edges of plots was associated mainly with more ears.

The efficiency of digestion and absorption is dependent upon the rate at which digesta moves through the gastrointestinal tract. The following report describes the gastrointestinal transit for digesta markers given to ten species of mammals fed the same diet.

The solitary larval parasite Microplitis rufiventris Kok was recorded for the first time in Egypt by El-Minshawy (1963), parasitizing the lesser cotton leafworm, Spodoptera exigua Hbn. Since it could be an effective summer parasite of the cotton leaf-worm, Spodoptera littoralis Boisd., studies on aspects of its biology by Hegazi (1976), and Hegazi, Hammad & El-Minshawy (1977) have been extended to include the effect of temperature on its development.

Vicia faba, in common with other grain legumes, rarely gives economic yield increases in response to soil application of nitrogenous fertilizer either before sowing or at flowering (McEwen, 1970a, b; Day, Roughley & Witty, 1979). The lack of response was attributed to poor uptake of the applied fertilizer particularly at flowering (Day et al. 1979). Garcia & Hanway (1976), however, increased the yield of soya beans from 3695 to 5225 kg/ha with foliar sprays containing N as urea, P, K and S applied during the seed-filling period. Day et al. (1979) using four foliar sprays of the same composition increased yield of V. faba by 361 kg/ha (8·6%) following the uptake of 15% of the 80 kg N/ha applied. However, Robertson, Hinson & Hammond (1977) reported no yield responses of soya beans with up to five foliar sprays of the same composition and noted that those containing ammonium polyphosphate and KNO3 caused leaf damage that significantly reduced yield.

Seed potatoes are grown on the high plateaux of northern Israel where it is cool enough for a summer crop. The seed are used for winter production of ware potatoes in southern Israel. Irrigation is essential because of the arid summers. It is customary to apply much of the N fertilizer through the irrigation system in numerous small doses. Total N rates have ranged between 300 and 400 kg/ha. In 1975 various aspects of N, P, K fertilization for seed potato (Solanum tuberosum L., var. Up-To-Date) production were examined. There were no responses to P or K fertilizers so only the N fertilizer responses are reported here.

Alternaria blight of sunflower caused by Alternaria helianthi (Hansf.) Tubaki and Nishihara is the most important disease of monsoon-grown sunflower crops in India (Kolte & Mukhopadhyay, 1973; Narain & Saksena, 1973). It is also reported to occur in Rumania (Hulea, Iliescu & Bunescu, 1975), Tanzania (Allen, 1974) and Brazil (Ribeiro et al. 1975). The present studies were carried out to assess the effect of different disease intensities on yield and oil content of the sunflower crop.