1. Two experiments involving length measurements of ninety-six bacon-pig carcasses showed that chopping out the backbones, chilling and laying the carcasses down on a table, each resulted in a decrease in average length. There was variation from carcass to carcass in the magnitude of these decreases which, in the case of the chopping out the backbone and laying down stages, was related to the fatness of the carcass, greater decreases being found in the longer, leaner carcasses than in the shorter, fatter sides.

2. Estimates of the precision of measuring showed that length from the junction of the first rib and the sternum to the symphysis pubis taken on hanging carcasses was less susceptible to errors than the same measurement taken on the lying carcass, and that both these measurements were more accurate than that from the atlas bone to the symphysis pubis taken on carcasses either hanging or lying.

The yield and chemical composition of Sabrina hybrid ryegrass and RvP Italian ryegrass were compared, with special reference to regrowth after defoliation in spring and early summer. Initial cuts were taken on 6, 20 April and 4. and 18 May; subsequently a conservation crop was harvested at either 5 or 7 weeks, and a second regrowth 30 days later. There were four fertilizer treatments. Tiller density, stem development and individual tiller dry weight were recorded in selected treatments.

At the initial cuts and in the conservation crops after the first three initial cuts, varietal differences in yield and dry-matter digestibility (DMD) were relatively small. In all other harvests, RvP was appreciably higher yielding than Sabrina, and it showed greater responses to fertilizer in all second regrowth harvests. The water-soluble carbohydrate (WSC) content of RvP was consistently higher than that of Sabrina in regrowth harvests; the DMD was higher in Sabrina.

In primary growth of the two cultivars, tillering was suppressed at the time of head emergence, but active tillering was resumed earlier in RvP, the later-heading cultivar. In RvP, tillers arising early in the regrowth periods attained head emergence within 5 weeks. In Sabrina there was a marked decline in head production during June, and an increase in the size of individual vegetative tillers.

In regrowth harvests both the yield and the % WSC were markedly reduced when drought conditions were most severe; the most marked varietal differences occurred at this time, both in terms of yield of dry matter and % crude protein responses to fertilizer treatment.

In the two cultivars the DMD of 7-week conservation crops harvested in late May was at least equal to that of 5-week crops harvested later during drought conditions. A distinctly more advanced stage of development was attained in the earlier, heavieryielding crops.

Vigorous cauliflower plants sometimes bear abnormally small curds, yet this common problem has received little recognition or attention from research workers. Curd size is often reduced towards the end of the harvesting period of a crop, and this is more marked if environmental conditions reduce mean curd size and lengthen the time to maturity. Small late curds may be a consequence of their slow growth rather than their late initiation. Cultivars differ in their tendency to produce plants with late maturity and small curds. This may not be due to genetic differences within cultivars. Moreover, breeding to eliminate or reduce this condition may not be possible without affecting overall maturity time and curd size.

Parametric approaches have been used widely to model animal growth and study the impact of growth profile on performance. Individual variation is often not considered in such approaches. However, non-parametric modelling allows this. Such an approach, based on spline functions, was used to study the importance of growth profiles from age 0 to 15 months (i.e. insemination) on milk yield and composition in primiparous cows. A dataset of 447 heifers was used for analysis of growth performance; 296 of them were also used to study impact on lactation. All of them originated from a French experimental herd and were born between 1986 and 2006. Clustering methods were also tested. Comparison of spline methods showed that a cubic spline interpolation method, with no smoothing parameter, was best suited to studying heifer growth. Similarly, partitioning around medoids proved the most accurate clustering method for classifying heifer growth into groups. The results of these analyses agreed with those previously published, supporting the utility of these methods. A final study on the impact of breakdowns in the growth curves was performed. A breakdown was considered only when the derivative of the interpolation function was negative or zero. Of the 447 heifers initially used, 125 (Gr0), 175 (Gr1) and 147 (Gr2) had no, one, or two or more breakpoints during the 0–15 months of age period. Milk yield on a 305 d basis was significantly reduced with an increased number of breakpoints (6548 v. 6828 and 6905 kg for Gr2, Gr1 and Gr0 animals, respectively). Fat content was also higher in Gr2 than in Gr0 groups, but overall, no difference in total fat or protein-corrected milk production was noted. The intersection between groups for growth and groups for breakdowns confirmed that animals with two or more breakdowns belonged more frequently to the group with the lowest growth performance. These results offer the possibility of analysing large databases, originating from an automatic collecting system (e.g. milking robots) or from different herds, breeds, genetics, etc. These approaches could also be used for studies on body score index, girth development, lactation profiles, etc. and in other species, such as dairy goats or beef cattle. They could find use in the development of new models of prediction, e.g. the probability of heat appearance on an animal basis, which could be included among useful management tools.

Fifty-nine Mutton Merino and cross-bred 2-year-old and older ewes were allotted to two groups according to age, weight and breeding performance in the preceding 1966/67 in-season. In the experimental ewes the treatment started on 22 March 1967 and consisted of vaginal sponges (Syncro-Mate) inserted for 17 days and 750 i.u./ewe of P.M.S. injected on the day of the removal of the sponges.

As from 1 March, all the ewes were ‘teased’ daily but hand service commenced on 20 April, to coincide with the 13th day after the removal of the sponges.

At the time of sponge insertion, approximately a third of the ewes, in each group, were already cycling. The treatment advanced the average post-treatment oestrus by 8 days, out of a possible 15 days, synchronized it in 70% of ewes and shortened the tupping season in 97% of treated ewes to 9 days (23 days in controls), but otherwise the performance of the treated ewes (and their offspring) did not differ from that of the controls. In both groups forty ewes lambed (68%) and fifty lambs were born (85%). Out of nineteen dry ewes, five were in anoestrus and in at least nine, an early death of the embryo could be suspected. Among the reproductive activities during the preceding in-season, date of weaning, days of suckling and barrenness may be implicated in the failure to breed in the spring.

Woodchip pads can be a sustainable alternative to the overwintering of stock on grassland or in conventional housing and can offer benefits in improved animal performance, improved health and environmentally sustainable options for the management of the effluent resulting from the animal excreta (dung, urine and rainfall over the pad). Detailed observations were made on effluent flow and quality from woodchip pads on two commercial farms in the UK, one in Powys (Wales) and the other in Leicestershire (England), over a period of 8 months in 2009/10. Flow data and hydrological characteristics, reported in the companion to the current paper (Jackson & Smith 2012), were combined with the results of effluent sample and soiled woodchip analyses, together with records of animal numbers and activity on the pads, to calculate nutrient fluxes and nutrient balances across the pad for defined periods. Nutrient balances showed that, of the estimated nutrient inputs in animal excreta deposited on the pad, only 0·05–0·10 of the N and P were contained in the effluent draining from the pad, with the rest (>0·90 of N and P inputs) retained in the solids accumulating in the surface layers of soiled woodchip, ‘spent timber residues’ (STR). The STR was similar in analysis to straw-based farmyard manure (FYM), high in organic N, and land spreading of this material should be managed in a similar way to FYM. It also appears suitable for application to grassland, except when based on coarse woodchips. These results confirm the hypothesis that the effluent draining from the pads should be considered as consistently similar to dirty water rather than slurry, as in the current rules associated with Nitrate Vulnerable Zones (NVZs) in England and Wales.

Six parental cultivars (Bragg, Bragg-black seed, Kalitur, Ankur, WT-125 and Glycine formosana), 15 F1's, eight F2's and eight F3's (Bragg × WT-125, Bragg × Glycine formosana, Bragg-black seed × WT 125, Bragg-black seed × Glycine formosana, Kalitur × WT-125, Kalitur × Glycine formosana, Ankur × WT-125 and Ankur × Glycine formosana) were evaluated for seed impermeability. WT-125 and Glycine formosana were identified as impermeable types (92·18, 77·46% impermeability, respectively). The other four varieties, namely Bragg (2·93% impermeable seeds), Bragg-black seed (11·7% impermeable seeds), Kalitur (no impermeable seeds) and Ankur (0·94% impermeable seeds) had soft seed or normal seed.

The segregation pattern for impermeability in the F2 and F3 generations of eight crosses showed the involvement of a pair of dominant genes in Bragg × Glycine formosana, Bragg-black seed × WT-125, and Bragg-black seed × Glycine formosana, three pairs of dominant genes in Bragg × WT-125, Ankur × WT-125 and Ankur × Glycine formosana, and four pairs of dominant genes in Kalitur × WT-125 and Kalitur × Glycine formosana for seed impermeability, assuming maternal control as hard seed was a seed-coat phenomenon.

Vr, Wr graphical analysis also indicated that WT-125 and Glycine formosana possessed mostly the dominant genes for seed impermeability, while the remaining four cultivars contained mostly the recessive genes. The correlation coefficient of Yr (parental mean) and Vr + Wr was negative and high (— 0·907) confirming that most of the dominant genes in the parental cultivars were acting towards high seed impermeability. Thus the overall results obtained through diallel analysis of 15 F1's were in agreement with those obtained through Mendelian analysis.

Various species of animals, ranging from ordinary laboratory rats to some high-grade beef and dairy cattle, have been imported from the temperate regions of the world to Nigeria in recent years. Most favoured are Large White pigs and this breed of livestock is proving to have very great potential in the livestock production industry in this part of the tropics. Temperate breeds of livestock when introduced to the tropics are said to decline in their general performance, owing partly to direct effects of high ambient temperatures(Yousef & Johnson, 1965). Some generalized statements have also been made on the adverse effects of tropical climate on growth though very little objective field experimental evidence exists (Williamson & Payne, 1978).

Stems of Dactylis glomerata were collected from grass-plots which had received different manurial treatment as regards potash.

The yield of hay from these plots was in close agreement with the average which shows that the season during which the work was done was not abnormal.

The thickness of the wall, the diameter of the lumina and the ratio of the lumen to the wall were measured both in sclerenchyma and metaxylem elements.

It was found that in the early stages the sclerenchyma walls were thinner where potash had been supplied, but that this effect was lost as the season progressed.

The lumina were larger in plants which had received potash, when nitrogenous fertilisers had not been added, but in the presence of ammonium salts, this effect was reversed.

In the xylem the thickness of the walls was unaltered whether potassic fertiliser were added or not. When no nitrogenous manures were added the diameter of the lumen was decreased in the presence of potash, but when ammonium salts had been applied, the diameter was increased by the application of potassic fertilisers.

The performance of Suffolk cross-bred ewe lambs produced either by Suffolk crossbred ewes, 70–90% Suffolk (HS), or by Ossimi ewes, 35–45% Suffolk (LS), was investigated. Forty-three ewe lambs from both groups were available, and were given two different levels of feeding.

The LS ewe lambs showed, insignificantly, better growth performance than the HS group, and breed group differences increased with age. They also reached puberty earlier (305·4 v. 334·6 days for the HS ewe lambs). Using the HS breeding rams rather than the imported Suffolk ones, for improving lamb production from the local sheep flocks, is recommended.

The LS ewe lambs started their first breeding season 18 days earlier, and ended 34 days later, than the HS ewe lambs. Both cross-bred groups showed clear anoestrous periods of 225·4 and 202·2 days, respectively. The onset of their second breeding season was similar, on average 29 August. These figures are close to those of the purebred Suffolk ewes, and far away from the nonseasonal local parents.

1. Experiments are described demonstrating a technique for raising sugar beet seedlings under glass during the winter to provide plants for seed production after transplanting into the field.

2. The use of 24 hr. illumination for this purpose is discussed, and the effect of this illumination in resolving a heterogeneous population is described.

3. The association between the growth habit of the seeding plant and root characters, glomerule yield, weight and size, and the time of anthesis is considered in relation to the recognition of types showing B. maritima and B. vulgaris characteristics.

The effects of changing plant density and nutrient supply on the yield of swedes were measured in nine experiments over 3 years. With small populations, a large nutrient supply was required to reach the maximal yield of roots, but with large plant populations the same nutrient rate depressed yield. This interaction is illustrated by a response surface, and reasons for it are discussed. The interaction is of limited importance in practice because it was small over the range of population and nutrient supply commonly used. Even with small populations, the compensation achieved by applying more fertilizer was uneconomic. On crops with large populations, such as swedes for human consumption, however, the normal recommended rate of fertilizer should not be exceeded because of loss of yield as well as increased cost. More fertilizer and greater plant density were needed to give maximal total yield (roots + tops) than of roots alone. Effects of nutrient supply and plant population on plant establishment and dry-matter content of the swedes are discussed.

1. An experiment was conducted to study the effects of progesterone and pregnant mare serum (p.m.s.) on incidence of oestrus, macroscopic changes in the ovaries, histological appearance of the genital tract, the vaginal smear and cervical mucus of New Zealand Romney Marsh ewes in deep anoestrus. Ten animals served as controls, thirty-five received progesterone daily for 4–12 days and ten were given p.m.s. alone. The remaining fifteen ewes were treated with progesterone for 4–6 days followed by p.m.s.

2. In ewes treated with progesterone alone, neither ovulation nor oestrus resulted. After p.m.s. alone six animals ovulated, while injection with both hormones caused ovulation in all 15 ewes and one was in oestrus.

3. Sections cut from the mid-region of the fallopian tube, uterine horn and cervix were examined. Histological responses to progesterone and p.m.s. were found in all positions of the tract and were greatest in the ewes which had ovulated.

4. In the ewes which ovulated a sequence of macroscopic and microscopic changes occurred in the vagina and these seemed similar to those associated with ovulation during the oestrous cycle.

5. Crystallization patterns in cervical mucus were seen in some ewes of all groups. Accompanying ovulation the phenomenon was seen for several days but was absent during most of the luteal period. When no follicles ruptured cervical mucus patterns often persisted. In most cases the presence and absence of arborization was presumably related to follicular oestrogen and progesterone from an induced corpus luteum and was in similar time relationship to that normally accompanying ovulation in the oestrous cycle. Some inconsistency in the response of cervical mucus following hormone treatment was noted.

6. No evidence was found that hormone treatment had initiated a regular cycle of ovarian activity.

Previous work has shown that the technique of laparoscopy in anaesthetized ewes is a practical and reasonably accurate method for the diagnosis of pregnancy between 17 and 28 days after conception and for estimating numbers of foetuses (Phillippo et al. 1972). This method in common with other reported endoscopic techniques for sheep positions the animal on its back, necessitating the use of either general anaesthesia (Roberts, 1968; Boyd & Ducker, 1973) or tranquillization and local anaesthesia (Kelly & Allison, 1976). These methods have the disadvantages of the necessity to withhold food and water for up to 24 h prior to surgery and the risk associated with general anaesthesia and the positioning of the animal. A new procedure with the sheep standing was therefore developed from the method used in cows (Mariana, 1969; Wishart & Snowball, 1973).

Some androgen-dependent constituents of seminal plasma of Sudan Desert rams were measured during the hot dry summer, the hot rainy season and the winter under tropical conditions in the Sudan. Higher concentrations of both fructose and citric acid were obtained between July and October during the rainy season and low values between January and April during winter, with marked monthly and seasonal variation in both characters. Considerable monthly variation in the hydrogen-ion concentration of semen was obtained with lower values between August and January and higher values between February and July. The androgenic status of the animals appears not to be decreased during the hot weather, but no explanation can be offered for the decrease during the winter.

This experiment was carried out in a newly reclaimed desert area south-west of Alexandria. The purpose was to study the effect of breeding Barki ewes more than once per year on body weights and mortality rates of their lambs. Lambs were weighed 24 h after birth and at the ages of 1, 2, 2·5 (weaning age), 3, 4, 5, 6, 9 and 12 months.

The experiment comprised three groups of single-born lambs of both sexes. The first group included 385 lambs born (in October–November) to ewes lambing once per year; tho second group comprised 155 lambs born (in January–February) to ewes lambing twice in twelve months and the third comprised 102 lambs also born in January–February to ewes lambing thrice in two consecutive years.

Lambs born to ewes lambing once were heavier from the age of 1 month to the age of 5 months than lambs born to ewes lambing twice in the same year or three times in two consecutive years. However, the three groups of lambs did not significantly differ in their body weights from 5 to 12 months of age.

Rebreedi ng did not significantly affect the mortality rate of lambs at the three studied ago periods, i.e. from birth to 1 month of age, from 1 month to weaning and from weaning to the age of 12 months.

Sex had a significant effect on body weights of lambs but did not affect their mortality rates.

1. Four cereal experiments, comprising 210 plots each about l/40th acre in area, were harvested by a sampling method. Three of the experiments were later harvested by large-scale methods, so that a direct comparison could be made.

2. The field technique is described, and an account is given of the small combined thresher and winnower which was constructed for the purpose of dealing rapidly with the numerous small sheaflets.

3. The results are analysed in detail and it is shown that the samplingerrors per plot lie between 5 and 6 per cent. of the mean yield, and that these errors are sufficiently low for there to be little loss of information.

1. The Valmari-Devarda method of estimating nitrates (i.e. distillation with magnesium oxide and Devarda's alloy) is unsatisfactory in presence of organic matter. Attempts to make it quantitative under these conditions by modifications of alkali and temperature proved unsuccessful.

2. Two new methods for the estimation of nitrate in plant juices are described. The first depends on the use of Devarda's alloy in cold weakly alkaline solutions, the second on the reducing power of titanous hydroxide, under conditions suitable for use with plant products.