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International audience; The absence of a full pedigree can hinder selective breeding efforts. In honeybees, definitive maternity and especially paternity of queens is difficult to determine, even under managed mating schemes (e.g. using artificial insemination) due to the negative effects of single-drone mating on colony fitness. Here we genotyped 388 living queens from two beekeeping operations using Genotyping-by-Sequencing (GBS). We evaluate two methods to call single-nucleotide polymorphism (SNPs), Tassel 5 and Stacks, for their ability to supply SNPs that can recover known relationships. While Stacks discovered more SNPs (29,433), SNPs called with Tassel 5 (16,757) were found to be more accurate for the derivation of relationships. This methodology presents a low-cost genotyping approach and can be used to support commercial honeybee breeding schemes.

Using internet-based software known as 1000Minds, choice-experiment surveys were administered to experts and farmers from the Irish sheep industry to capture their preferences with respect to the relative importance – represented by part-worth utilities – of target traits in the definition of a breeding objective for sheep in Ireland. Sheep production in Ireland can be broadly separated into lowland and hill farming systems; therefore, each expert was asked to answer the survey first as if he or she were a lowland farmer and second as a hill farmer. In addition to the experts, a group of lowland and a group of hill farmers were surveyed to assess whether, and to what extent, the groups’ preferences differ from the experts’ preferences. The part-worth utilities obtained from the surveys were converted into relative economic value terms per unit change in each trait. These measures – referred to as ‘preference economic values’ (pEVs) – were compared with economic values for the traits obtained from bio-economic models. The traits ‘value per lamb at the meat processor’ and ‘lamb survival to slaughter’ were revealed as being the two most important traits for the surveyed experts responding as lowland and hill farmers, respectively. In contrast, ‘number of foot baths per year for ewes’ and ‘number of anthelmintic treatments per year for ewes’ were the two least important traits. With the exception of ‘carcase fat class’ (P < 0.05), there were no statistically significant differences in the mean pEVs obtained from the surveyed experts under both the lowland and hill farming scenarios. Compared with the economic values obtained from bio-economic models, the pEVs for ‘lambing difficulty’ when the experts responded as lowland farmers were higher (P < 0.001); and they were lower (P < 0.001) for ‘carcase conformation class’, ‘carcase fat class’ (less negative) and ‘ewe mature weight’ (less negative) under both scenarios. Compared with surveyed experts, pEVs from lowland farmers differed significantly for ‘lambing difficulty’, ‘lamb survival to slaughter’, ‘average days to slaughter of lambs’, ‘number of foot baths per year for ewes’, ‘number of anthelmintic treatments per year for ewes’ and ‘ewe mature weight’. Compared with surveyed experts, pEVs from hill farmers differed significantly for ‘lambing difficulty’, ‘average days to slaughter of lambs’ and ‘number of foot baths per year for ewes’. This study indicates that preference-based tools have the potential to contribute to the definition of breeding objectives where production and price data are not available.

Pregnant mares in New Zealand are often kept at pasture with inadequate copper (Cu) concentrations according to National Research Council (1989) recommendations. Many authors recommend Cu supplementation of pregnant mares to reduce the degree and severity of developmental orthopaedic disease (DOD) in their foals. Few data exist on the efficacy of Cu injections in mares in raising liver Cu concentration in pregnant mares or their foals, or the pattern of normal decline in liver Cu concentration of foals after birth. In this study pregnant mares were treated with injectable Cu, or saline, in two different regimens, in 2 consecutive years. Mares and foals had liver biopsies harvested to determine the effect of mare Cu supplementation on liver Cu concentration, and to identify normal patterns of decline in foal liver Cu concentration from birth to 160 days of age. Injectable Cu supplementation had no significant effect on dam or foal liver and plasma Cu concentration. A mathematical model to describe...

The unique Pere David's (Elaphurus davidianus) x red deer (Cervus elaphus) backcross hybrid has been used to search for evidence of quantitative trait loci (QTL) for antler pubertal (date and live weight at pedicle initiation) and antler seasonality (date of antler cleaning and casting) traits in temperate species of deer. Analyses using marker information revealed evidence for a QTL for date at pedicle initiation (LOD = 3.7) and live weight at pedicle initiation (LOD = 3.1). These QTL explained 13% and 11% of the phenotypic variance in these traits, respectively.

Asian markets for velvet antler perceive the colour of the core as a primary indicator of quality. The factors which influence colour are not known, but the market preference in Korea is for an even mid‐red colour. The aim of the present study was to determine whether removal technique and post‐removal handling influence velvet colour. Investigations took place at AgResearch Invermay and at Mount Hurt Station in mid Canterbury, New Zealand. The influences on velvet antler colour of sedative drug, mild stress, local anaesthetic administration, timing of tourniquet application, and restraint of the stags in a crush or workroom for velvet antler removal were investigated. The effects of antler orientation post‐removal and post‐removal environmental temperature on velvet antler colour were also investigated. In all studies, velvet antler was frozen and held at ‐20°C before being dried either by freeze drying or commercially. In all trials, a consistent pattern of both lightness and hue angle was show...

Objective To determine the changes in Ca, P, Mg, Na, K, S, Cu, Fe and Zn concentrations of milk during the lactation in pasture-fed Thoroughbred mares and then calculate the dietary mineral requirements of the sucking foal and the lactating mare. Procedure Milk was sampled on days 1, 3, 7, 14, 21, 28 and at various times between 55 to 65, 85 to 95 and 135 to 150 days after parturition from 21 pasture-fed mares. The concentrations of macro- and micro-elements in the milk were determined by inductively coupled plasma emission spectrometry. Results Concentrations (mg/L) of these elements were highest in colostrum (Mg 302, Na 561, K 955, S 1035, Cu 0.76, Fe 0.79 and Zn 5.5) except for Ca (1245) and P (895), which where highest on day 7. The mean milk mineral element concentrations (mg/L) over days 55 to 150 were Ca 843, P 543, Mg 47, Na 120, K 590, S 219, Cu 0.19, Fe 0.34 and Zn 2.1. The mean plasma element concentrations (mg/L) over the same period were Ca 120, P 77.1, Mg 17.0, Na 3110, K 168, S 983, Cu 1.1, Fe 1.5 and Zn 0.49. Concentration gradients between plasma and milk were observed and, in the case of Ca, P, Mg, K and Zn, their concentrations in milk were greater than those in plasma, while a reverse situation was observed for Na, S, Cu and Fe. Conclusion With the exception of Ca and P, the highest concentrations of mineral elements were observed in the colostrum. The nursing foal should have access to good pasture or creep feed, because the intakes of Ca, P and Cu from milk may be less than optimum to meet the daily mineral element requirements.

The objective of this study was to determine whether Mo causes secondary Cu deficiency in pasture‐fed horses. Twelve Thoroughbred weanling fillies were divided into two groups and fed either high Mo pasture (8 to 15 mg Mo kg−1 DM) or a low Mo pasture (0.6 to 1.2 Mo kg−1 DM) for 84 days. Both pastures contained 6 to 9 mg Cu kg−1 DM. The animals were challenged with Cu over the last 14 days to determine change in their Cu status to 1.0 mg Cu kg−1 liveweight d−1 given orally three times a week. Copper status was assessed from liver, plasma, blood cell, and plasma trichloroacetic acid‐insoluble Cu concentrations as well as the enzyme activities of plasma caeruloplasmin and red blood cell superoxide dismutase. None of these indices was affected by the increase in Mo intake. Horses grazing pasture high in Mo responded no differently to Cu challenge than did those on low Mo pasture. The results of this study suggest that Mo is unlikely to increase dietary Cu requirements and induce secondary Cu deficien...

The allometric relationship (Y = AX b ) between velvet antler weight (Y) harvested at 2, 3, and 4 years of age and the respective winter lean liveweight (X), was examined in 145 farmed red deer stags (Cervus elaphus). The stags which were the progeny of 10 sires, were born in 1982 and 1983. The allometric coefficients (b) for the 1982‐and 1983‐born stags were 2.4 and 1.7 respectively which indicated that velvet antler was late maturing relative to winter lean liveweight. Sire had a significant effect on the scaling factor (A, P < 0.05) of the allometric equation, which indicated that over the liveweight range in this study, there was up to a 30% difference in velvet antler weight adjusted for winter lean liveweight for stags from the different progeny groups. The sire effect on the relationship between velvet antler weight and winter lean liveweight indicates the possibilities for selection of genetically superior sires for velvet antler production relative to winter lean liveweight.

The five fattest and five leanest rams were selected on the basis of their liveweight-adjusted ultrasonic backfat thickness from a flock of 100 Coopworths at around 6 months of age. A total of 110 male progeny of these 10 rams were slaughtered between January and April at a mean hot carcass weight (HCW) of 17.13 kg. There were no significant differences between sire classes (i.e., lean, fat) in the weights of the progeny (HCW of 16.95 and 17.31 kg, SED ±0.621). However, there were very marked differences in the regression slopes for the allometric relationships between several carcass variables and HCW, with the lean class having significantly lower slopes for carcass chemical fat content and three subcutaneous fat depths than the fat class. The estimated heritability for backfat thickness (progeny-sire regression) was 0.25. The results indicate that significant progress in terms of carcass leanness should be achievable through the use of suitable ultrasonic devices for measuring backfat thicknes...

Ewes hcterozygous (1+) for the Inverdale prolificacy gene (FecX’) located on the X chromosome have ovulation rates about 1.0 units higher than noncarriers. The purpose of this study was to examine the reproductive performance of ewes that were either heterozygous or homozygous (II) carriers of the Inverdale gene. Carrier rams (I) were mated with heterozygous ewes (1+) to produce females, half of which were expected to be 1+ and half II. The 59 female progeny were examined by laparoscopy at 8 mo or 1.5 yr of age; 48% were found to have nonfunctional “streak” ovaries, which were about one eighth the volume of normal ovaries and showed no sign of follicular activity. There were four examples of full sib pairs where within each pair one had normal ovaries and the other had streak ovaries. Since these streak ovaries have not been observed in ewes known to be 1+ or noncarriers (+ +), it is concluded that this condition is associated with animals homozygous for the Inverdale gene.

In a flock of highly prolific Romney ewes obtained from industry flocks, one ewe (A281), with a production record of 33 lambs born in 11 lambings, produced a number of female descendants with high ovulation rates. The mode of inheritance of this trait was determined in a series of four progeny tests of male descendants of this ewe. The first progeny test produced strong evidence for a new major gene affecting ovulation rate in this family line; this finding was supported by two subsequent progeny tests. The fourth progeny test was designed to test the hypothesis that this gene is carried on the X chromosome. The results showed that six sons of a carrier ram did not inherit the gene, but it was passed on to three of his five maternal grandsons. This finding, together with evidence of genetic segregation in the progeny of carrier females, demonstrates for the first time the presence of a major gene for prolificacy specifically located on the X chromosome. The effect of the gene is to increase ovulation rate by about one additional egg per ewe.

The concurrent and long-term effects of feeding high (H) and low (L) levels of nutrition from weaning to 4 years of age were measured in 188 high fecundity heterozygous Booroola Merino × Coopworth (BC) ewes (FecB Fec+) and 58 low fecundity New Zealand Merino × Coopworth (MC) ewes. Following the cessation of differential feeding, all groups were grazed on a common plane of nutrition for 2 years. There were no significant nutrition by genotype interactions for liveweight, lamb performance, or ewe lambing performance. During common feeding, carryover effects of restricted feeding were apparent only for liveweight and barrenness. The mature liveweight of H ewes was 60–70 kg throughout differential feeding, which was 12–15 kg heavier than L ewes. L ewes showed 58% compensatory growth but were still 5.1 kg lighter than H ewes (P < 0.05) at the end of the experiment. Ovulation rates of L ewes were 0.07–0.51 lower than their H contemporaries during differential feeding and this was significant (P < 0.05 ...

In a series of experiments, involving 372 lambs over 2 years, the effects of subcutaneous implants of Cimaterol (CL263, 780; anthranilonitrile, 5-[1-hydroxy-2-(isoproplyamino)ethyl]-), in young sheep grazing pasture were examined. Treatment with Cimaterol increased carcass weight gain by 37% averaged over the experiments. Wool growth was reduced by 16% in the experiments where it was measured. Cimaterol treatment also increased dressing percentages by 1.3-3.7 percentage units, increased the cross-sectional area of L. dorsi muscle, and decreased fat depot weights and subcutaneous fat thickness measurements in all experiments. These changes were accompanied by increased protein and water contents and a decreased fat content in the carcass. Analysis of the growth rates of carcass components revealed that the changes were a consequence of marked increases in the rates of carcass protein deposition (up to c. 3-fold) in Cimaterol-treated lambs accompanied by markedly reduced rates of lipid deposition. ...

Despite the large number of active programs breeding improved forage plants, relatively little is known about the weightings that breeders consciously or sub-consciously give to specific traits when selecting individual plants, or that agronomists and producers use when assessing the relative merits of contrasting cultivars. This is in contrast to most modern animal breeding programs where the relative merits of novel genetics may be assessed against an index-based breeding objective. There are numbers of reasons why these technologies have not been used widely in plant breeding although applications in forest tree breeding are relatively common. A first step in defining breeding objectives for forage species can be to define the relative importance of specific traits and to interpret how these contribute to the relative potential advantage to a new plant or cultivar. One method of defining these weightings is through surveys of users followed by analyses of their combined experience. Therefore in this study, we have assessed the usefulness of discrete choice techniques in the development of weightings for specific traits in forage plant improvement based on views of both expert users (agronomists and farm consultants) and farmers who were asked to define their relative priorities when considering the renovation of a pasture. The surveys were conducted in three distinct regions of, or environments within, Australia of special relevance to meat production from beef and sheep (high rainfall, temperate (inland), and Mediterranean). In summary this study defines the focus of breeding objectives and selection criteria for different pasture species across production systems.

Interspecies hybrids between Pere David's deer (Elaphurus davidianus) and red deer (Cervus elaphus) have proved to be a powerful resource in the search for quantitative trait loci (QTL) in deer. Several regions of the genome with significant effects on live weight and growth rates in backcross hybrids were detected. These include putative QTL for 6-month live weight (LOD 3.90) on linkage group 12, for 14-month live weight (LOD 3.19) on linkage group 1, three putative QTL for growth rate from 3 to 6 months (LOD 4.19 on linkage group 12, LOD 3.92 on linkage group 12, and LOD 3.34 on linkage group 5). In addition, linkage groups 20 and 1 appear to be associated with live weight traits between 9 and 16 months. The variance in traits explained by these QTL ranged between 5.3% and 11.2%. Allele substitution with Pere David's alleles at different loci had both positive and negative effects on live weights and growth rates.

Growth in temperate and arctic deer is seasonal, with higher growth rates in spring and summer while growth rates are low or negative in autumn and winter. We have measured IGF1 concentrations in the plasma of reindeer calves exposed to a manipulated photoperiod, indoors, of either 16 hours light followed by 8 hours dark each day (16L:8D) (n = 3) or 8L:16D (n = 3) from about the autumnal to the vernal equinox, to determine whether the seasonal growth spurt normally seen in spring is associated with changes in the circulating level of IGF1. A high quality concentrate diet was available ad libitum. The animals were weighed, and bled every 2 weeks and plasma samples assayed for IGF1 by radioimmunoassay. 6-8 weeks after the start of the study those calves exposed to 16L.-8D showed a significant increase in plasma IGF1 concentration which was maintained until the close of the experiment, 24 weeks after the start. In contrast IGF1 plasma concentrations in those calves exposed to a daylength of 8L:16D did not significantly alter during the study. The elevated IFG1 in the 16L:8D group was associated with rapid weight gain compared with the 8L:16D group. We have shown that the seasonal growth spurt is preceded by an elevation in plasma IFG1 concentration. Further, this elevation in IGF1 is daylength dependent. For comparison IGF1 and growth rate seasonal profiles from temperate and tropical deer are included. This comparison reveals that seasonal increases in IGF1 take place only in animals with a seasonal growth spurt. Thus IGF1 plasma level elevations seem most closely associated with the resumption of rapid growth in spring following the winter.

Blood from stages aged 15 months (n = 6) was sampled at monthly intervals every 30 min for 24 h for 12 months, at 45 degrees S in New Zealand. Three extra samplings each for 24 h were carried out at about the anticipated time of antler casting. All samples were analysed for luteinizing hormone (LH) and testosterone and the resulting data further analysed by the Pulsar pulse detection routine. The animals were kept indoors under natural daylength and were fed ad libitum. All animals were weighed, antler status and size recorded and testes diameter was measured on each sampling day. Mean LH and testosterone pulsatily and plasma concentration varied seasonally. LH pulse frequency was low during autumn (2.5 pulses in 24 h), winter (1.0-1.5 pulses in 24 h) and early spring (1 pulse in 24 h) and lowest in late spring (0.2 pulse in 24 h) before rising in summer (1.0-4.0 pulses in 24 h). LH pulse amplitude and mean plasma concentration were low (< 1 ng ml-1) from March to November (autumn-spring); both rose to a peak in January (summer) of 3.4 and 1.6 ng ml-1, respectively. Testosterone pulse frequency was generally similar to LH except that slightly more pulses of testosterone than of LH were detected from March to November and more pulses of LH from November to February (summer). Testosterone pulse amplitude fell from March to November (5.3 ng ml-1 to undetectable) although there was a conspicuous peak in July (midwinter) of almost 5 ng ml-1.(ABSTRACT TRUNCATED AT 250 WORDS)

Body and carcass characteristics were determined for 128 wether and ewe lambs from the mating of Invermay lean and fat Coopworth selection line rams to randomly selected Romney ewes. The lambs were grazed from 5 to 8 months of age on a tussock grassland overs own with either lotus (Lotus pedunculatus Cav.) or clover (Trifolium sp.) at two allowances, 2 kg (low) or 4 kg (high) dry matter per animal per day. When adjusted to mean cold carcass weight, sire genotype was the only treatment to affect carcass chemical composition. The lambs by lean sires had more water and protein and less fat in their carcasses than the lambs by fat sires. The lean lambs were also heavier and had carcass fat depths that were 15 – 33% lower. In comparison, any significant effects of diet and allowance on subcutaneous fat depths or carcass chemical composition were smaller.

Six red deer stags from age 4 months were kept in a light-proof room under an artificial photoperiod consisting of 5.5 cycles of alternate 2-month periods of 16 h light and 8 h dark (16L:8D) and 8L:16D. At 2 or 3 weekly intervals from 10 months of age through 4 cycles, the stags were anaesthetized with xylazine and challenged i.v. with 10 micrograms GnRH. Blood samples were withdrawn immediately before and 10 and 60 min after injection. LH and testosterone concentrations were measured in all samples by RIA. Antler status was recorded daily. Peak LH values on each sampling day occurred in the sample taken 10 min after GnRH stimulation while peak testosterone occurred in the sample taken at 60 min. There were 4 cycles of LH and testosterone secretion accompanied by 4 antler cycles in the stags. The highest LH responses were detected during short days (8L:16D), and the highest testosterone responses were detected around the time of the change from short to long days. The responses of both hormones were lowest at the end of periods of long days or the beginning of short days. The increased pituitary LH response to GnRH was evident 4 weeks after the change to short days which are stimulatory for gonadal development. Antler casting occurred at the end of long days and cleaning at the end of short days. It is considered that antler cycles were due to the ability of the stags to vary release of LH and testosterone in response to changes in the artificial photoperiod.