This paper describes the relationships between large-scale modes of climate variability and its related weather types with the fluctuations in the yield of maize crops in Veneto, Italy. The teleconnections analysed in this work are the winter North Atlantic Oscillation (NAO) and the summer North Atlantic Oscillation (SNAO); the West African monsoon (WAM) and the Intertropical Front (ITF). Despite that these indices are not rigorously linked to one another, they result in being considerably related to atmospheric circulation regimes and associated weather types. They have an impact on temperature and precipitation patterns in Italy and on yields of maize crops in Veneto, a region located in northeast Italy. Yields are strongly affected by large-scale temperate and tropical variability directly through three main circulation regimes. Troughing weather regimes that produced below average temperatures depress yields over the entire Veneto region, as does the zonal regime that affects rainfall. Results confirm the relevance of large-scale modes and associated weather regimes and types on maize crop yields fluctuations in Veneto.

This paper assesses the influence of heat and drought stress on the economic performance of the European dairy sector. Climatic data from the Gridded Agro-Meteorological data in Europe were combined with dairy enterprise data from the Farm Accountancy Data Network, resulting in a data set of 4412 farms in 22 European Union (EU) countries over the period 2007–2013. Since the performance of dairy farms is influenced by the context in which they operate, farms were grouped into areas representing similar climatic conditions through the use of a latent class analysis. Technical efficiency (TE) and economic downside risk were used as performance indicators against which the effect of climatic stress factors was evaluated. TE was estimated using a ‘true-fixed’ effect stochastic frontier model. Economic downside risk was based on gross margin deviations. Regression analysis suggests a significant negative effect of drought and heat stress on both TE and the downside gross margin difference in most climatic classes, with few exceptions. Results imply that both drought and heat stress-related issues need to be considered when designing adaptation strategies to address threats to the economic performance of the EU dairy sector.

Forage is the primary feed source for livestock in tropical regions and energy is one of the most important nutrients for ruminant nutrition. The effects of harvest management of Marandu palisade grass (Brachiaria brizantha cv. Marandu Syn. Urochloa brizantha cv. Marandu) on non-structural carbohydrate (NSC) concentrations were evaluated. A plot (Experiment 1) and a greenhouse study (Experiment 2) were conducted in 2013–14. In Experiment 1, treatments were the factorial arrangement of two harvest times and two vertical canopy layers (upper and intermediate), distributed in a completely randomized design with five replicates. In Experiment 2, treatments were the factorial arrangement of six harvest times and two morphological fractions (leaf blade and pseudostem). In both experiments, NSC concentration increased during the day. Upper and intermediate canopy layers had greater NSC concentration at 15.00 than 06.00 h during spring and summer. In addition, the magnitude of NSC increase was greater in the upper than intermediate canopy layer and in spring than summer. Marandu palisade grass shows greater digestibility in the afternoon than morning, representing an opportunity to optimize energy concentration through harvest management.

Dry bean (Phaseolus vulgaris L.) is a traditional crop of north-western Macedonia, Greece, where two landraces (plaki Prespas and Chrisoupoli) in particular are grown. The aim of this study was to test whether the grain carbon isotope discrimination (Δ) and ash content (ASH) are related to grain yield (GY), protein content (PC) and mean grain weight (MGW) in dry bean. As a part of a honeycomb selection programme, 21 genotypes (19 lines derived via intra-landrace honeycomb selection for single plant yield at low density plus the two original populations) were grown at two densities, 1·2 and 4·8 plants/m2 under non-limiting water conditions in a glasshouse and in the field. Genotypes differed significantly for Δ, ASH and PC under the low density. In the dense stand, genotypes differed significantly only for ASH and PC. The environment (glasshouse or field conditions) affected all the traits significantly. Neither Δ nor ASH showed strong or consistent relationships with GY and thus, they cannot serve as reliable, indirect selection criteria for GY. Strong, negative relationships between Δ and PC were found especially in the dense stand, confirming analogous results in C3 cereals. Inconsistent genotypic ranking for grain physiological traits under the different densities and environments was indicative of large genotype×environment interaction. Genotypes performed consistently for GY and MGW under both densities, showing the strong stability of these traits.

The use of selective breeding to reduce methane (CH4) emissions is an option for reducing carbon emissions from livestock farming systems. The current study models UK lowland terminal sire (meat) sheep production systems to study the impacts of including CH4 emissions and/or feed intake as breeding objective and selection criteria traits in sheep breeding systems, on the predicted genetic responses of production traits. Nine breeding goal traits and 15 selection index traits were modelled in a Suffolk breeding flock with a deterministic model of trait economic values (EVs). Methane was given an EV equivalent to a carbon price varying from £0 to £538/t CO2-e. When currently used selection indices added feed intake as a breeding objective, CH4 reductions of 0·15 and 0·05 kg CO2-e/sheep/year were predicted when intake was, or was not, measured, respectively, with a zero carbon price. These reductions were relatively insensitive to carbon price. Overall economic (index) response to selection was insensitive to carbon price and increased with higher feed costs, when neither CH4 nor feed intake was measured. When CH4 and/or intake were measured, overall economic responses increased with higher carbon prices, when feed costs were zero. Methane and intake responses were only sensitive to carbon price (whether CH4 and intake were measured or not) when feed costs were zero. To achieve a desired reduction of 0·1 kg CH4/head/year (cumulative 30% reduction in 20 years) when feed costs were zero, CH4 and/or intake needed to be measured. If CH4 was measured, carbon price needed to be >£50/t CO2-e; if intake was measured carbon price needed to be >£100/t CO2-e. Including feed intake as a breeding objective trait with non-zero feed costs should assist in reducing CH4 in breeding programmes. Selective breeding of terminal sheep by index selection has the potential to contribute a reduction of up to 0·27 kg CO2-e per ewe per annum, depending on the traits measured, feed costs and carbon price. This would help meet the UK Government's greenhouse gas reduction targets for farming systems.

The utilization of different levels of protein, supplied mainly as soybean meal, was examined by a feeding experiment with sheep. Measurements of the concentrations of N-containing rumen metabolites and of blood urea showed that protein degradation in the rumen and removal of urea by the kidneys were limited when highly increased amounts of protein were ingested.

1. Two panels of eight students, with no previous experience in scoring bacon sides for eye-muscle qualities or for fatness, co-operated in an experiment involving thirty-five photographs of back rashers of bacon presented to them in batches of twenty at a time. The members of the first panel made their assessments without any guide, whereas those of the second were provided with sets of photographic reference standards showing a graded sequence of rashers scoring from 0 to 10 for each of the two characteristics involved.

2. Those provided with the reference standards spread out their scores over the available range more than those who judged without them.

3. Judging discrimination between markedly different groups of rashers was improved when the reference standards were available. This was not true of discrimination between similar rashers since repeatability of scoring was to some extent decreased when the standards were used.

4. When the reference standards were not available, these inexperienced judges tended to adjust their level of scoring according to the quality of the batch of rashers being assessed. This adaptive effect was eliminated when reference standards were available although apparently random fluctuations of level of scoring from batch to batch still occurred.

5. Differences between judges due to their different uses of the available range of scores were less marked, although not entirely eliminated, when reference standards were used by the naive judges. Systematic differences between the scores awarded by various judges remained, as did a few differences of opinion on the relative quality of certain examples.

Root growth of rice (Oryza saliva L.) is frequentlyinhibited by an adverse physical environment resulting from high moisture stress and strength of soilunder upland conditions, and the effects are often reflected in poor performance of the crop. This necessitates a critical understanding of rice root growth under varying soil physical conditions.

The growth responses of the rice root system to the interaction between moisture regime and bulk density of soil as well as to the induced soil physical characteristics were assessed under controlled glasshouse conditions. Four moisture regimes: 0 (M1), 0–20 (M2), 0–350(M3), and 350–10000 (M4) mb, were superimposed on low, medium and high bulk density treatments in clay, loam and sandy loam soils. The soil physical environment was characterized by measurements of moisture distribution, penetrationenergy and oxygen diffusion rate in soils as functions of depth.

A low moisture stress of 20 mb in low density soils favoured rice root growth. In low density soils, even though the number of roots at the base (proximal end) was maximum under M1, the depth of penetration, volume and dry weight of root were significantly more underM2 than under M1; M3 and M4. Irrespective of bulk density, even though oxygen diffusion rates in soils under M3 and M4 were greater than those under M1 and M2, the number of roots at the base, volume and dry weight of the root system decreased under M3 and M4 owing to low moisture content and high penetration energy in the surface layer (0–5 cm) of all the soil types. Lower moisture content and higher penetration energy at higher bulk densities of the soil types significantly reduced the root growth and especially the depth of penetration.

Three creep rations were fed in the form of meal, pellets and ground pellets. The compositions of the first two rations were similar to those of the rations used in general farming practice; the compositions of the pellets and ground pellets were identical. The experiment was carried out for 8 weeks from birth at thirteen centres and involved a total of 152 litters. No difference between meal and ground pellets was found in either food consumption or weight gain. Pigs on pellets consumed 18% more than pigs on meal, but this did not result in a significant improvement in weight gain. Treatment × centre interactions were not significant.

Crop rotation serves as a mechanism for developing sustainable crop production systems. Crop-rotation trials are used to identify agronomic input factors suitable for use in a cropping system. In crop-rotation trials, experimental errors within the same plot over time are correlated. The form of the covariance structure of the plot errors may be specific to the data from a rotation trial, but is unknown and is generally assumed. Statistical analyses are usually based on the assumption that plot errors are independent, or have constant covariance. An experiment was conducted using wheat-based, three-course rotations containing tillage treatment subplots over 12 years at ICARDA's experimental station at Tel Hadya, a moderately dry area in northern Syria. This study examined several covariance structures for temporal errors arising over the rotation plots and tillage subplots, in order to model wheat yield data. Eighteen covariance structures were examined, and the best pair was selected using the Akaike Information Criterion. The best pair comprised first-order autocorrelation and homogeneous variance for temporal errors in rotation plots, and uniform correlation with heterogeneous variances for temporal errors in tillage subplots. Using the 12 years of data obtained for wheat yield and the best pair of covariance structures, the tillage and rotation effects were found to be statistically significant and to have significant interactions with the cycle of rotation. The precision of the means calculated differed from those calculated using a control structure based on homogeneous error variances and constant correlation. The cumulative yield build-up over time differed significantly over the rotations and the tillage methods. An increasing yield trend was observed for the bread wheat rotation, while a yield decline was observed in durum wheat when the rotation was repeated. When evaluating the effects of input factors in crop rotations, we therefore recommend that the covariance structures be examined and that a suitably chosen structure be used.

In a previous paper (Pizer, 1937) it has been shown that the physical state of composted horse manure is of great importance as regards the growth of the mushroom mycelium. A granular condition obtained by flocculating the manure with small amounts of calcium—0·5 part of calcium per 100 parts of dry compost, wt./wt. —is most suitable for rapid, vigorous growth, while a dispersed greasy condition arising through a shortage of calcium is very unfavourable and may prevent growth entirely. In both flocculated and dispersed composts, mycelial growth is made more vigorous by small additions of a soluble phosphate, equivalent to 0·031 g. phosphorus per 100 g. of dry compost. Further experiments dealing with the practical application of these results are described in the present paper. The calcium compounds used were commercial flake calcium chloride (26),1 ground gypsum (24), superphosphate of lime (21) and hydrated lime (53), the latter being used in error for ground carbonate of lime (38). All these materials, except hydrated lime, were found to be satisfactory in laboratory trials for promoting mycelial growth, but the best results were given by the first three. The materials differ greatly in composition and properties, in ease of application and reactivity, and probably in their influence on the metabolism and productivity of the mushroom, and it was the main object of the experiments to discover the most suitable one for the grower to use.

Five agricultural by-products, maize stover and cobs, wheat straw, grape marc and sunflower husks, were treated with alkaline reagents under various conditions.

Maize stover and wheat straw reacted quickly with both sodium hydroxide applied at a level of 4 g NaOH/100 g dry residue and a mixture of calcium and sodium hydroxides (1:1), which led to changes in chemical composition and increases in digestibility. However, ensilage of the treated product at about 37% dry matter (D.M.) was not successful.

When dried grape marc was treated with sodium hydroxide (4·3 g NaOH/100 g dry residue) apparent lignin content increased, although other changes in composition and digestibility were similar to the above. Nevertheless, digestibility remained low. Moreover, when previously ground marc was treated in the same way lignin and cellulose fractions increased markedly while digestibility decreased.

Treatment of maize cobs with increasing amounts of sodium hydroxide (2·1–4·2 g/100 g dry residue) at 80% D.M. gave progressively more favourable results, although no improvement in digestibility was noted when half the sodium hydroxide was replaced by calcium hydroxide. Similar positive results were obtained under industrial conditions at application rates of 3·2 and 4·5 g sodium hydroxide per 100 g dry residue. Pelleting the product led to a further increase in digestibility.

Sunflower husks also showed a decrease in hemicellulose content and increases in digestibility and volatile acid content after treatment with 4·4 g NaOH/100 g dry residvie under industrial conditions. Lignin content was unchanged. The pelleted products (about 80% D.M.) were stable for more than 6 months when stored in paper sacks.

Except with grape marc loss of hemicellulose provided a general indication of the success of alkali treatment, although correlation with increased digestibility did not reach statistical significance (r = 0·34). Volatile acid production and alterations in lignin content were not suitable as general indicators.

In general, alkali treatment of the examined materials improved digestibility, although the products with a high water content were subject to undesirable fermentative changes during storage and therefore should be used within a few days.

The effect of nitrogen fertilizer and irrigation treatments on the leaf-area index (L) and net assimilation rate (E) of a monthly cut sward of Italian ryegrass (Lolium multifolium) is considered.

Response to nitrogen was due to increase in both L and E, whereas response to irrigation was largely due to increase in L.

The data show little evidence of a seasonal decline in E. This may have been due to the mid-season replacement of old tillers by new, and by the encouragement to new leaf production caused by periodic harvesting.

Internal and external follicle diameters of both primary and secondary follicles of Texel x Ossimi and Merino x Barki ewes were greater, at birth, than those in either respective parent breed; the density of primary follicles at birth was less in the cross-breds than in the parental breeds, for both crosses. There was a greater increase of follicle diameter with age in the Egyptian breeds, and mean follicle diameters of the crossbreds were intermediate between those of parent breeds at ages of 3–6 months and above.

Grading up Ossimi sheep with the Caucasian Merino resulted in progressive decrease of mean internal follicle diameter. The F2, with more merino blood, had a greater frequency of the smallest diameter follicles than had the F1.

An attempt has been made to ascertain the best interval between calvings, so that the cow's average weekly yield over a long period may be at a maximum. It was only possible to consider the case of the “average cow,” but it is claimed that the general principle has been established, that cows should calve at intervals of not less than a year, and not more than thirteen months; this optimum will probably be subject to a slight variation in particular cases. This is approximately the state of affairs in practice—though Norfolk farmers appear to err on the side of serving too early in the lactation, rather than too late.

At three sites in the Sudan Gezira the variations in seed cotton yields between 1941 and 1961 were due, in the main, to variations in insect pest damage and, at one site only, to a downward trend in soil nitrogen level.

At each site seed cotton yield was predetermined by total plant top dry weight before the opening of the first cotton bolls. The cotton crop was sown in August. At Turabi in the northern Gezira and at the Gezira Research Station in the south-central Gezira, variations in plant growth up to early October had little effect on subsequent yield. The yield was determined by growth during October, November and December; the total top dry weight at the end of December was much more important than the pattern of growth by which this weight was attained. At these sites yield was much more closely dependent on the amount of leaf recorded as free from pest and disease damage than on total leaf weight. Damage due to jassid (Empoasca lybica), thrips (Caliothrips spp.) and leaf curl accounted for 69% of the year to year yield variation at Turabi. Damage due to jassid and thrips accounted for 56% of the year-to-year variation at the Gezira Research Station.

Severe pest damage was associated with low July plus August rains and high temperatures during the growing season but was not found to be dependent on leaf nitrogen levels.

At Hag Abdulla in the southern Gezira, there was a general downward trend in yields over the years as well as variation from year to year consequent on variations in thrips damage. The downward trend inyields was associated with a trend to lower soil nitrate and plant nitrogen levels which resulted in anearlier cessation of leaf growth in recent years than hitherto.

Variation in the level of pest attack accounted for 61% of the year-to-year variation in nitrogen response at Turabi, while at Hag Abdulla the response to nitrogen was determined by the deleterious effect of thrips and by a trend to increasing response as natural soil nitrate levels declined.

Gezira commercial crop yields were closely correlated with those of the appropriate experimental plots for the years considered (r = 0·859 for the S-type crop, 0·736 for the L-type crop) inspite of some differences in cultural practice. This suggests that the major causes of variation were the same in both cases and that adequate protection against insect pests should do much to prevent the recurrence of seasons of extremely low yield with their serious economic consequences.

One of the commonest grasses found in hedges and thickets in this country, more especially on the lighter soils, is the Tall Oat Grass (Arrhenatherum avenaceum, Beauvais). In meadows it is generally present, abundantly on some soils, while occasionally it forms part of the “seeds” mixture put down for temporary or permanent pasture. In some localities a form of this grass known as “Onion Couch” becomes a dangerous weed on the arable land—this plant is identical in outward appearance with the Tall Oat Grass except at the base of the stems where the nodes swell and form chains of bulbs each of which is capable of breaking off and giving rise to a new plant. This habit of growth together with a liberal supply of seeds formed in June and July make it a very difficult weed to eradicate. Its occurrence is usually reported from the lighter soils, but in the West of England the heavy land is equally badly affected.

Research into the mechanisms that control the initiation and development of wool follicles has been severely hampered by the inaccessibility of fetal skin in utero. The aims of this study were to determine whether ovine fetal skin, when grafted onto the athymic nude mouse (nu/nu), could be maintained outside the uterine environment and, if so, whether it would retain its ability to initiate and develop wool follicles capable of producing wool fibres.

Skin was removed from the mid-side region of ovine fetuses on days 45, 55, 65, 75, 85 and 95 of gestation, and transferred to graft beds prepared on anaesthetized nude mice. After developing for 20 days on the recipients, the grafts were excised for histological examination. Control ovine fetal skin was also obtained at the above times and from fetuses on days 105 and 115, and similarly processed for histological examination.

Fetal skin at all ages was successfully grafted onto nude mice; 90% of all grafts were accepted and maintained by the recipients. Follicle initiation and/or development occurred in all grafts, including those formed from day 45 fetal skin, collected and grafted prior to follicle initiation in vivo. The number of follicles in grafted skin was reduced compared to that in control fetal skin of equivalent age; however, follicle development was generally accelerated. Follicle initiation and development occurred predominantly in the peripheral zone of the grafts. Some of the follicles present in the skin at grafting were lost due to the grafting procedure, while others continued to develop and produce wool fibres. Follicle development varied considerably between grafts. All grafted skin exhibited premature loss of the periderm layer and cornification of the epidermis, probably in response to the exposure of the skin surface to the atmosphere. There was a notable absence of both arrector pili muscles and sweat glands associated with graft follicles, and a retardation of sebaceous gland development.

The grafting technique developed in this study has enabled ovine fetal skin to be maintained outside the uterine environment for extended periods of time and may provide an improved means for future investigation of wool follicle initiation and development.

Data representing 1928 lambing records were analysed to study the effects of inbreeding and cross-breeding on lamb survival to the ages of 7, 30, 120 and 180 days. The sheep flock consisted of two native breeds, Barki (B) and Rahmani (R); and the imported Fleisch Merino (M) as well as the crosses M × B and M × MB. Analysis was made by fitting a least-squares linear model that included the main effects of year and season of birth, sex, age of dam, type of birth, inbreeding of the lamb (Fd) and the dam (Fd) and breed group and the interactions season × type of birth, season × Fo and season × breed group. Lambs were classified into six groups according to the magnitude of the inbreeding coefficient: F ≤ 0·05, 0·05 < F ≤S 0·10, 0·10 < F ≤ 0·15, 0·15 < F ≤ 0·20, 0·20 < F ≤ 0·25 and F > 0·25. The average inbreeding coefficient in the flock was 0·12 and 0·08 For the lambs and their dams, respectively.

Sex of lamb and age of dam had no significant effect on lamb survival at any age while single-born lambs had a higher (P < 0·01 or P < 0·05) survival than twins at all ages except 7 days. Inbreeding of the lambs showed significant effect at 7 and 120 days. Increase in inbreeding of the dams was associated with higher mortality at all ages but the trend was not significant.

Differences among breed groups were not significant at 7 and 30 days, but were highly significant at later ages. The contribution of breed group to the total variance in survival increased with age. Hybrid vigour was highly significant in both crosses at 120 and 180 days.