Abortion and stillbirth ranges of 1·8–16·1% and 1·26–6·5% respectively have been reported among Friesian cattle by Asker & El-Itriby (1957), Ragab & Asker (1959), Juma (1968) and Kassir & Juma (1968). Abortions and stillbirths occurred more frequently among heifers than among cows (Philipsson, 1971). Calving interval varied between 367 and 474 days, the first interval being the longest (Ragab & Asker, 1959; Zaki, Abdel Razek & Dessouky, 1965; Marples& Trail, 1967; Trail &Marples, 1968; Anon. 1969; Knudsen & Sohael, 1970; McLntyre, 1971; Kiwuwa, 1972).

Prof. T. B. Wood in the November issue of the Journal of the Ministry of Agriculture discussing the known methods of estimating the nutritive values of foodstuffs says, “there is a method which is within the scope of any experimenter and is capable of yielding accurate results of great practical value,” and he goes on to give examples, in the estimating of the nutritive value of swedes, kale, etc., using the results of an experiment which entailed the use of 40 to 120 animals. From these experiments he gets results showing a very satisfactory agreement between experiment and calculation, notwithstanding that there must be a slight experimental error in the calculation of food consumed.

Four lambs (mean 27 kg liveweight) offered 900 g/day lucerne chaff were prepared with catheters in the portal vein (PV), cranial mesenteric vein (CMV), femoral artery (FA) and abomasum. L-[2,6-3H]phenylalanine (Phe) and 14C-(Phe)casein were infused into the abomasum in separate experiments. Concurrent samples of blood from the PV, CMV and FA were prepared as four fractions: plasma, deproteinized whole blood, free Phe in deproteinized whole blood, and whole blood. Ratios of net label uptakes in different blood fractions indicated that red blood cells and blood proteins were unlikely to contribute to net Phe uptake into the PV or CMV. Small peptides may have contributed up to 20% to total appearance of Phe in the PV and CMV. However, net uptake of peptides from the lumen was probably zero. It was concluded that the Phe uptake and, by implication, total amino acid uptake from the lumen of the small intestine into the PV and CMV were as free amino acids.

Chlorophyll contents per unit leaf area and unit dry weight, chlorophyll a:b ratio, visual colour rating, specific leaf area, and leaf fresh weight: dry weight ratios were estimated for 12 couch (bermudagrass) varieties (Cynodon spp. L.) in winter (July) and spring (October). Net photosynthetic and dark respiration rates were estimated in winter only.

The chlorophyll contents per unit leaf area were higher in all varieties in spring than in winter, but per unit weight were more variable. The varieties differed substantially in the net photosynthetic and dark respiration rates. The specific leaf areas were greater in winter than in spring in five varieties: in others it changed little. The fresh: dry weight ratios of the leaves were almost constant between varieties in the spring but varied greatly during the winter. Visual colour ratings were well correlated with chlorophyll contents per unit area but not with weight. The net photosynthetic rate was closely correlated with chlorophyll content (per unit area) but not so closely with colour rating.

Experiments were conducted in Bangkok clay soil to investigate the influence of planting date, tiller separation and plant density on the yield and yield attributes of parent and clone plants of two transplanted rice varieties. The 15 July transplanting of mother crop and collected vegetative tillers and retransplanting on 15 August showed significantly high grain yield (3·8 t/ha). The photoperiod-insensitive variety RD23 gave higher yield (3·8 t/ha) than the photoperiod-sensitive variety KDML105 (3·0 t/ha). Tiller separation up to 4 tillers/hill did not adversely affect the mother crop. Vegetative tillers transplanted with 2–4 tillers/hill gave a similar yield as the mother crop in both the seasons. Vegetative tillers gave a higher yield than nursery seedlings transplanted on the same date. The yield components, i.e. weight of 1000 grains, grains/panicle and per cent filled grains, showed better responses with early transplanting of KDML105 in the mother crop and vegetative tillers except for panicle number and panicle length of vegetative tillers with RD23. The results suggest that in some flood-prone lowlands, where the transplanted crop is damaged by natural hazards, vegetative propagation using tillers separated (maximum 4/hill) from the previously established transplanted crop is beneficial for higher productivity.

Literature dealing with disposal of farm wastes is mainly concerned with smell, heavy metal toxicity, nutrient accumulation and soil physical conditions. Soil is required to filter and absorb the solid material and release a filtrate free from pollutants while remaining relatively unaltered. The importance of soil type in reducing pollution potential is recognized but little study has been made of the effect of pollutants on soil morphology. This paper reports changes observed in a fine silty and fine loamy typical brown earth of the Rheidol series on terrace gravels after treatment with pig slurry. It is concluded that pig slurry spread at the rate of 50 m3/ha per week will cause this permeable soil to deteriorate under an average rainfall of 1117 mm/year unless rest periods are given.

The present work extends the information on the skin thickness of cattle and shows that generalizations made in previous work were only partly correct, for there are significant differences only between the skin thickness of the Zebu ‘races’ of tropical cattle and Bos taurus.

Again there appeared to be no significant difference between animals of different ages within breeds.

The work confirmed that cattle of eleven tropical breeds comprising four of the major ‘races’ of African indigenous cattle have a significantly thinner papillary layer than temperate breeds, and this was very strongly correlated with their superior heat toleration.

Further support based on wider premises was therefore given to suggestions made by Dowling regarding the importance of the histology of the skin in heat toleration.

The objectives of the current study were to compare and model feed intake responses to ambient temperature across species and to assess opportunities to use cross-species (CS) data to parameterize models when species-specific (SS) data were limited. Literature searches were conducted to identify studies reporting intake during thermal stress compared with thermoneutral (TN) conditions. The resulting data set comprised 614 treatment means from 108 studies on livestock responses to thermal stress. An analysis of variance was conducted with the CS data set to identify the effects of species, temperature and species by temperature interactions on intake as (fractional feed intake; FFI). Four models were derived from the CS data set and root mean squared prediction error (RMSPE) and concordance correlation coefficients (CCC) of these models were compared with models of the same form derived from SS data sets. Models used explanatory variables for (1) duration of exposure; (2) mean temperature; (3) minimum and maximum temperatures; or (4) difference between minimum and maximum temperatures. An additional model accounting for temperature and stage of production was derived from the SS data. Analysis of variance demonstrated that the species by temperature interaction did not have a significant effect on FFI. Across species, intake decreased with temperature. Notably, all species demonstrated a constant decrease in intake across the TN zone indicating the previous assumption of constant intake during thermoneutrality may be not fully valid. When compared on a SS basis, SS-derived models had marginally lower RMSPE and higher CCC when compared with models derived from the CS data sets. The model fit with production data had the lowest RMSPE and highest CCC within the study. When compared over temperature ranges with minimal data available in some species (e.g., cold stress), using CS models often resulted in decreased RMSPE and improved CCC when compared with SS models. Although fitting models based on SS data allows for incorporating unique covariates, like level of production, fitting responses based on CS data can help to improve model estimates when knowledge gaps exist.

Adrenaline was infused at three rates, 40, 15 or 3 μ/kg/h, in normal sheep and in sheep rendered hypercortisolaemic by infusion of cortisol at 150 μg/kg/h. In both normal and hypercortisolaemic animals, plasma concentrations of glucose and free fatty acids were increased by adrenaline treatment; plasma phosphate decreased with all treatments; plasma magnesium and potassium decreased on infusion of adrenaline at 40 or 15, but not at 3 μg/kg/h; plasma calcium decreased only on infusion of adrenaline in hypercortisolaemic animals, and plasma sodium concentration was unaffected by treatment.

Induction of a degree of lipolysis likely to occur in the field was not associated with a marked decrease in plasma magnesium.

Hofuf-Alhassa is one of the important agricultural areas of the Kingdom of Saudi Arabia. The water available for irrigation purposes is limited in quantity and saline in nature.

To maximize the use of available water sources, a technique is described to mix irrigation water with drainage water, taking into consideration the salt balance effect in the soil under the Alhassa conditions.

Under intermediate deepwater (15–50 cm) conditions, sulphur-coated urea (SOU) drilled behind the plough at sowing was superior to other coated (neem, lac, coaltar) urea materials and broadcast incorporation of prilled urea in increasing the yield of direct-sown rice. In transplanted rice, the grain yield was highest with urea super granules (USG) placed 30 days after transplanting (DAT) followed by SOU broadcast incorporation at planting. N-use efficiency increased considerably with SCU drilled behind the plough or USG placed 20 days after sowing in shallow standing water in direct-sown rice and SCU broadcast incorporation or USG placed 30 DAT in transplanted rice.

Measurements have been made of the electrical conductivity of aqueous suspensions of stored soil samples taken at intervals of several years from four of the Rothamsted classical plots bearing the same crop every year. The results show that under continuous cropping:

1. The initial conductivity (and therefore the soluble salt content) of an unmanured soil decreases steadily to a minimum value, which then remains fairly constant over a long period of years. There is reason to believe that, under the same conditions, the normal initial conductivity of a continuously manured plot (excluding the temporary increased measurements due to application of manure) decreases similarly to a fairly constant minimum value, which is slightly greater than that of an adjacent unmanured soil depending on the kind and probably on the quantity of manure applied.

2. The 7 days’ increase of both unmanured and manured soil decreases progressively. In the case of an unmanured soil for which earlier samples were available, the 7 days’ increase is found to decrease comparatively rapidly during the first few years of continuous cropping.

The results of an experiment, conducted over one cycle of a four-course rotation to study the effects of nine nitrogenous fertilizers on crops and soil, are described.

All the crops gave fairly good responses to nitrogen but in no case was there a significant difference between the effects of the various nitrogenous fertilizers. The “recovery” of added nitrogen was about 40–50 % with all the fertilizers.

Figures are given for the changes in exchangeable CaO content of the soil. The results confirm Crowther and Basu's deduction that “the loss of calcium exceeds that for equivalent nitrogen added as nitrate by an amount equivalent to the excess of anions over the cations in the added fertilizer, all added nitrogen being regarded as nitrate and all carbon and phosphates being ignored”.

The fact that phosphate should be ignored is shown by results for mono- and diammonium phosphates. Precipitation of phosphates in the soil almost certainly involves removal of calcium from the exchange complex but the calcium in such precipitated phosphates is exchangeable.

Since phosphate has no effect on calcium status, it is clear that fertilizers based on ammonium phosphates remove less calcium from the soil than do mixtures based on ammonium sulphate and superphosphate.

Reduced glutathione (GSH) is synthesized within blood erythrocytes from the constituent nonessential amino acids, glutamic acid, cysteine and glycine. The concentration of GSH in. erythrocytes can therefore be affected by the permeability of erythrocyte membranes to certain of these amino acids and their availability within the erythrocyte (Young, Ellory & Tucker, 1976; Smith, 1977). Alterations in the activity of the two enzymes responsible for GSH synthesis, γ-glutamyl cysteine synthetase and glutathione synthetase can likewise influence GSH concentration (Smith, Lee & Mia, 1973; Blume, Paniker & Beutler, 1974; Wellner et al. 1974; Board, Morris & Peter, 1976).

It has been reported recently (Stott, 1974) that in cattle, reproductive efficiency is increased by keeping the animals under cool climatic conditions. However, in buffaloes very limited information is available. Roy, Sengupta & Misra (1962) have reported that all buffaloes exhibited oestrus and were inseminated in a group protected from direct sun radiation whereas in a non-protected group only one showed oestrus. There is no systematic information available on the effect of wallowing and showers on the oestrual behaviour of buffaloes. Therefore, the present investigation was undertaken to study the effect of cooling on oestrual behaviour in buffaloes.

The efficiency of the utilization of the energy of casein in adult fowls at different feeding levels both for maintenance and for lipogenesis, was studied. The casein was utilized for maintenance with an efficiency of 66·6 ± 1·3% of the gross energy and of 83·7 ± 1·4% of the metabolizable energy. For lipogenesis efficiencies were 51·6 ± 2·15%, and 61·3 ± 2·6% respectively.

Glasshouse and field experiments were conducted in 1993 at the International Livestock Research Institute (ILRI) in Addis Ababa to identify effective combinations of Trifolium semipilosum genotypes and Rhizobium leguminosarum bv. trifolii strains and to investigate the effects of waterlogging of Vertisols on the response of clover to inoculation. In the glasshouse, the Rhizobium strain ILCA372str produced nearly ten times as much nodule DM, three times as much shoot DM, five times as much root DM, and twice as much plant N on cv. Safari as it did on accession ILCA7609 under normal watering conditions. This spontaneous streptomycin-resistant mutant strain performed better than its parent strain. Shoot DM and N yields of this combination were, however, only 55 and 71%, respectively, of the corresponding N-fertilizer (150 kg N ha−1) treatment. Waterlogging reduced nodule DM by 33%, shoot DM by 41%, root DM by 25% and N yield by 33%, and responses of both plant genotypes to inoculation and to N fertilizer were reduced. In the field, there were no significant differences in nodulation, plant DM and plant N between seed and soil inoculation methods. Dry matter and N yields of Safari inoculated with strain ILCA372str were at least twice as high as those produced by any other strain or N fertilizer supplied at 100 kg N ha−1. Waterlogging during early establishment in the field probably reduced the availability of N fertilizer to the plants. Further field testing of the Safari-ILCA372str combination is recommended, particularly in combination with broad-bed and furrow (BBF) technology to drain Vertisols.

Animal recording is an interactive process that involves several practices. The efficiency of the process is essential to ensure the utility of outcomes necessary for sustainable participation. Most evaluation approaches define efficiency in economic terms. Animal recording systems lack outputs of direct economic benefits; hence, efficiency evaluation based on utility derived from the records would be more laudable. In that case, a system is considered efficient when outcome-utility-dependent participation is sustained. Approaches for evaluating efficiency based on the utility of outputs are, however, unavailable. The current study presents an approach for evaluating the efficiency of animal recording based on output utility using the institutional analysis and development framework. The approach evaluates efficiency by incorporating institutional issues influencing the operations of the system and its outcomes. It considers animal recording as an action arena with various actors in three action situations, namely: animal identification and registration, pedigree and performance recording and animal evaluation and information utilization. The variables include the positions occupied by actors, their actions, the outcomes associated with the actions, the level of control over choice, available information and the cost and benefits of engagement. As an interactive process, animal recording has rules that order relationships between actors. It also exists within a biophysical system and community whose attributes, combined with the rules, influence the actions and outcomes of recording. These are evaluated by looking at rule formation structures, enforcement and compliance and the level of interaction between the recording system and other biophysical characteristics and the community for their effects on outcomes, their utility and sustainability of recording. Participatory tools, Stakeholder matrix and Venn diagrams are used to identify the variables, quantify their interactions and link them to outputs. The applicability of the approach is tested using a case where information systems are imperfect. The approach successfully identifies missing actors within the action arena, poor rule conformance due to weak enforcement agencies and the absence of rules that govern outcomes and ensure the utility of outcomes as hindrances to the utility of recording and hence the efficiency of the system. It may therefore be used to evaluate the efficiency of systems whose outputs do not have a direct market value and in situations where quantitative market information is scarce.

A standardized butcher-type method (B) in which anatomical reference points were used to determine cutting lines was compared with a semi-anatomical method (A) in which the jointing was based still more closely upon the anatomy of meat animals. Thirty-two lamb carcasses were split by hand sawing and the sides prepared for quartering, quartered and finally jointed into five hindquarter and five forequarter joints by one or other of two operators by either method A or method B according to a pre-arranged plan. Operator bias in the preparation of the sides for quartering was only noteworthy for the removal of internal fats.

Method A proved to be more consistent than method B, but the degree of advantage varied for different joints. In terms of the coefficients of variation for different joints by the two methods, method A had an advantage in consistency over method B for eight of the ten joints into which each side was divided.

The reproducibility of the semi-anatomical method (A) could be further improved by adopting more fully anatomical methods of joining.

The application and implications of an anatomical method in the excision of sample joints is noted.

In a study with chicks, the metabolizable energy (ME) values of two maize and two wheat offal samples were estimated using regression procedures in which the ME of the fishmeal supplement, common to all diets, was first calculated.

From chemical analysis, the wheat offal samples would have been expected to yield at least as much ME as oats, but results fell short of expectation by as much as a quarter in the case of one sample of wheat middlings. The significance of these findings is discussed.

By comparison with previously determined ME values on the same samples fed to sheep, the chicken tended to metabolize more of the maize energy and less of the wheat offal energy.