Adult Hinds Research Articles

Productivity of farmed wapiti in Alberta

Calving and weaning rates of 1084 wapiti hinds (females) were collected in the 1990 season by an on-farm survey of 50 producers in Alberta, to determine the reproductive performance of farmed wapiti. A calving rate of 81 and 96% for 2-yr-old and adult hinds, respectively, gave a provincial herd average of 93%. Weaning rates of 73% for 2-yr-old and 91% for adult hinds resulted in an 88% weaning rate overall. One set of triplets and three sets of twins gave a multiple birth ratio of one in 271 calvings. Overall calf mortality was 5.2% in the survey, with a trend (P = 0.07) for 2-yr olds to experience higher calf mortalities (9.5%) than adult hinds (4.4%). Dystocia accounted for two-thirds of the total calf mortalities reported in the survey. Although 2-yr olds calved later than adult hinds (11 June vs. 6 June), hind pre-rut weight influenced calving dates. Male calves were heavier (94 vs. 85 kg, (P = 0.0001) than female calves at 100 d due to their faster growth rate (753 vs. 686 g d−1, P = 0.0001). Growth rate and consequently weaning weights were positively influenced by hind pre-rut weight. The mean length of the breeding season was 111 d with producers exposing an average of 21 hinds per breeding stag on 1.2 ha of pasture per wapiti yr−1. The calf production ratio at 200 d was 52.5 kg calf per 100 kg hind for individual females weaning a calf, and was 46.2 kg calf per 100 kg of hind exposed on a herd basis. Pre-rut weaning was associated with improved calving (3.3%), weaning rates (2.6% in adult hinds and 13.4% in young hinds), decreased calf mortality (3.2%), advanced calving dates (5 d), and improved growth to 200 d (8%). Key words: Game farming, wapiti, reproduction, calving, weaning, growth

Cloprostenol-induced luteolysis in the red deer hind: the effects of age, dose, number of corpora lutea and the later stages of the oestrous cycle

The luteolytic effectiveness of the prostaglandin F 2α analogue, cloprostenol, was investigated by monitoring plasma progesterone concentrations. In Experiment 1, pubertal ( n=20) and adult ( n=20) hinds had their oestrus synchronised by intravaginal delivery of exogenous progesterone for 14 days. Fourteen days after progesterone withdrawal 0, 100, 250 or 500 μg of cloprostenol was administered intramuscularly and blood samples were collected by jugular venepuncture. All cloprostenol treatments were equally effective in lowering progesterone concentrations in both age groups. Twelve hours after administration, progesterone concentrations averaged 41% of pretreatment values for the three treated groups and at 24 h were 26% of pretreatment values. However, in some hinds (eight pubertal and four adult) luteal regression was incomplete and progesterone concentrations increased within 24–48 h of the onset of treatment. In Experiment 2, adult hinds ( n=28) were treated to induce synchronised oestrus with either mono-ovulation or superovulation induced with combinations of pregnant mare's serum gonadotrophin (PMSG), follicle stimulating hormone (FSH) and gonadotrophin releasing hormone (GnRH). Hinds were then allocated to receive 750 μg of cloprostenol intramuscularly at either 11 or 15 days after progesterone withdrawal (9–10 or 13–14 days after oestrus). Plasma progesterone concentrations in hinds with single and multiple corpora lutea, were reduced within 6 h of cloprostenol administration, and continued to decline thereafter. Cloprostenol induced complete luteolysis in all 13 hinds treated on Day 15 but in only six out of the 12 hinds treated on Day 11. The six hinds (four mono-ovulation, two superovulation) in which luteolysis appeared incomplete were characterised by short-lived reductions in progesterone concentrations. These results indicate that cloprostenol is luteolytic in both young and adult red deer hinds and in hinds with multiple corpora lutea. However, its effectiveness may be incomplete in some animals.

Haematological reference values for farmed red deer (Cervus elaphus) in New Zealand

An automatic haematology analyser (Technicon H6000/C) providing red cell, white cell and platelet parameters was calibrated for the blood of red deer Cervus elaphus. Haematology reference values for these parameters, plasma viscosity and plasma fibrinogen are presented for defined groups of female weaner red deer (n = 123), adult red deer hinds (n = 86) and weaner male red deer (n = 37), the latter being bled using physical restraint and also using xylazine sedation. Age, sex, sedation and season-related differences were found. Reference values are also presented for serum haptoglobin in adult hinds and levels were similar to those seen in cattle.

Behaviour and weight change of red deer calves during different weaning procedures

Two studies were carried out to examine the effectiveness of confinement indoors and the presence of adult hinds in reducing stress in farmed red deer calves separated from their dams for weaning at 3–4 months of age. In a preliminary pilot trial, 30 male and 30 female calves were weighed and randomly allocated to five groups of 12 animals (six males and six females). Each group was assigned to a different treatment: not weaned, or weaned and then confined in a paddock or indoors for 7 days, with or without two hand-reared hinds added to the group of calves during confinement. Activities observed over 5 days following weaning differed between the groups. The unweaned group spent the most time lying in sternal recumbency, indoor groups spent the most time standing and eating, and the outdoor group without hinds spent the most time pacing the fenceline. Analysis of variance revealed that both confinement indoors and the presence of hinds improved weight gain over the 7-day period following weaning. In an experiment carried out to determine how the presence of hinds might reduce weaning stress, 90 calves were allocated randomly to 15 groups of six. The distance maintained by the calves from: (a) a human, and (b) a novel object was tested, with either no adult hind ( n=5 groups), or one of two hinds ( n=10 groups) added to the group. Groups with a hind present showed less fear of the human and the novel object, and the behaviour of the groups varied according to the particular hind they were tested with. It was concluded from the two experiments that both confinement indoors and the presence of a hind were effective methods of reducing weaning stress, and that the hind reduced fear responses in the calves.

Influence of prenatal photoperiod on postnatal prolactin secretion in red deer (Cervus elaphus)

Plasma prolactin concentrations were higher (P < 0.001) in newborn red deer calves whose mothers had been maintained for the last 14 weeks of gestation in long days (18 h light) (group L, n = 9) than in those whose mothers had been kept over the same period in short days (6 h light) (group S, n = 5). After transfer of all hinds and suckled calves on the day of birth to constant intermediate daylength (12 h light), prolactin concentrations decreased exponentially (P < 0.001) in group L calves, but not in group S, during the first 21 days. Thereafter, prolactin fell to a nadir in group L calves and rose to peak values in group S calves at 8-12 weeks post partum (P = 0.003), before converging again by 14 weeks. The pattern of prolactin secretion over the first 14 weeks of life was therefore significantly affected by prenatal photoperiod. Plasma prolactin concentrations in the adult hinds were higher (P < 0.001) in group L than group S at 4-10 weeks before parturition; they were similarly high around parturition and fell thereafter to baseline values after 7 weeks. These results provide evidence that deer fetuses respond to photoperiodic information, thereby acquiring a photoperiodic history in utero that influences postnatal responses to photoperiod.

Hoof and foot loads for reindeer (Rangifer tarandus)

Hoof and foot measurements and body weights were taken from 60 living semi-domesticated reindeer (Rangifer tarandus tarandus L.) (8 female and 13 male calves, 10 young females (age 2 yrs), 9 young males (age 2-3 yrs) and 20 adult hinds) at the Kaamanen Reindeer Research Station during the winter 1988. The outline of the hooves and the feet (hoof + dew claws) from front and hind legs were drawn when pressed down on a hard substrate in a natural position. Measurements were taken also from foot prints of 26 wild forest reindeer (R. t. fennicus Ldnn.) (7 calves, 11 hinds and 8 stags) made on hard snow surfaces in Kuhmo and Salamajarvi national park during 1985-88. Reindeer had bigger hooves and feet on front than on hind legs, and male calves had bigger hooves and feet than female calves. Hoof and foot areas of wild forest reindeer (means 74.6 and 200.3 cm2 for calves, 79.4 and 230.4 cm2 for hinds and 83.6 and 258.6 cm2 for stags) were bigger than those of semi-domesticated reindeer (means, front legs, 60.9 and 165.3 cm2 for calves and 78.9 and 214.1 cm2 for hinds, respectively). There were significant correlations between live weight and hoof areas (r=0.839 and 0.792), between live weight and foot areas in front and hind legs (r = 0.714 and 0.664) and between live weight and foot area when supported by 4 legs (r = 0.726) in semi-domesticated reindeer. Load on ground and foot load in semi-domesticated reindeer when supported by 4 legs were 235 and 85 g/cm2 in calves and 268 and 102 g/cm2 in hinds.

Use of urine samples collected from bladder and snow to indicate condition of semi-domesticated reindeer

Arctic and subarctic reindeer respond to energetically costly winter conditions by behavioral modifications and physiological adaptations. Blood usually permit quantification of this integrated response to variations in nutrition (Nieminen 1980). Recently the search for indicators of nutrition in animals has turned to urinalysis (see DelGiudice et al. 1988). Urinalysis has been employed by Eriksson and Valtonen (1974) for freely grazing semi-domesticated reindeer in Finland. Altogether 52 semi-domesticated reindeer (49 adult females and 3 castrated males) were used in present study. Reindeer were freely grazing in Kaamanen Reindeer Research Station or fed with rouhage (dried Equisetum fluviatile) or concentrates (Poron-Herkku, Raision Tehtaat Oy) during winter and summer 1989. During winter reindeer were grazing mainly Cladina lichens and during spring and early summer common reindeer forage plants (see Nieminen and Heiskari 1989). The blood samples were taken from the jugular vein and blood serum parameters were determined by standard methods (see Nieminen 1980). Urine samples from the bladder of castrated males were collected during slaughtering and those of living females by catheterization. After sampling reindeer were weighed. Urine samples in snow were collected from different feeding groups using the method by DelGiudice et al. (1988). Urine samples were poured into snow and collected as described by DelGiudice et al. (1988). Urine and urine-snow samples were kept at 20°C until analysed. Urea N and creatinine were assayed by spectrophotometry. Urea and creatinine ratios were calculated. The obvious disadvantage of urinalysis in wild species may be the difficulty of urine collection. Urine collection from bladder of adult reindeer females by catheterization during spring and summer was, however, nearly 100 % successful. During winter time it was slightly difficult to collect samples because urine content in the bladders was very low. The decline in water flux of reindeer during winter is about five to sevenfold compared with that during summer (see White 1975). There were no significant differences in body weight between different reindeer groups in present study, but body weights decreased slightly during winter and spring, and the lowest body weights were measured for the adult hinds in June after calving. Significant differences were found in blood parameters between different reindeer groups at same sampling date. Some significant differences were also measured in blood parameters between different sampling dates indicating changes in nutrition and nutritional status of reindeer. The highest serum urea: creatinine (U:C) ratios were measured for ad libitum fed hinds and freely grazing hinds in June. There was significant positive correlation between serum urea and bladder urine urea in present study (r = 0.504, n = 28, P < 0.01). Significant positive correlations were also found between serum creatinine and bladder urine creatinine values (r = 0.729, n = 28, P < 0.001), and between serum U : C and bladder urine U : C ratios (r = 0.920,

A note on melatonin-treated red deer stags advancing the onset of the calving season in hinds

ABSTRACTThe effects of treating adult red deer hinds nutritional demands to coincide better with and stags with exogenous melatonin on the food production on improved pastures. One calving season in hinds were evaluated in a 2 such method has been the administration of × 2 factorial experiment. Treated stags were implanted with melatonin monthly beginning in December and hinds post calving in January, Melatonin advanced the timing of rutting behaviour in both treated stags. Calving date was significantly influenced by melatonin treatment of hinds (a mean 10-day advancement; P &lt; 0·01) or stags (12-day advancement; P &lt; 0·001). The interaction of hind and stag treatments was not significant, however treatment of both sexes resulted in the greatest advancement in mean calving date (21 days; P &lt; 0·001). These results indicate that treatment of red deer hinds or stags with exogenous melatonin can result in an earlier calving season and suggest seasonally advanced stags can stimulate earlier breeding activity in hinds.

Performance and population dynamics in relation to management of red deer Cervus elaphus at Glenfeshie, inverness-shire, Scotland

Most of Britain's red deer live at high density on some of Britain' least fertile land, i.e. poor hill-land in Scotland, which has lost most of its original woodland. For well over a century, deer have been actively conserved on such land, on privately owned estates known as ‘deer-forests’, devoted mainly to deer-stalking (i.e. stag hunting with a rifle), but with venison output also becoming important latterly. This land is both atypical and suboptimal as red deer habitat, and these deer are markedly poorer in performance than those in their more usual woodland habitats elsewhere. For information relevant to improved harvesting, red deer were studied over a 9-year period at Glendeshie, a 16 600 ha deer-forest in the Cairngorms. Here the population density was 30% higher than average for Scottish hill-land, and deer performance was comparable with other high-density populations in Scotland. Early growth was slow, and puberty in hinds relatively late. Whereas some hinds in low-density populations can be sexually mature as yearlinhs ( 1 1 2 - year-olds ), no pregnant yearlings or lactating 2-year-olds occurred at Glenfeshie. Each year, about 34% of the adult hinds failed to breed, giving rise to the high frequency of ‘yeld’ adult hinds which typify populations in this type of habitat. The birthrate of about 44 calves per 100 hinds was probably a little lower than average for Scottish hill-land, but much lower than in the best red deer habitats where all hinds are mature as yearlings and able to breed every year thereafter. Apart from losses of calves soon after birth, most natural mortality was in late winter and early spring, but the incidence was quite low over the study period due to unusually mild winters. The main causes seemed to be under-nutrition and exposure which affected individuals already in poor condition, i.e. stunted youngsters and adults past their best years. It was estimated that the population could sustain an annual crop of about 15% of the adult stock, this being about twice the traditional level. Although carcase-meat production (about 1 kg ha −1 year −1) would be still low by agricultural standards, such land would otherwise be difficult to exploit, and other income arises from leasing out stalking. However, the actual cropping-rate would have to be reviewed periodically; it would be impossible to anticipate the effects of severe winters or of neighbouring management changes. Therefore, much depends on regular stock assessment, and since individual deer-forests seldom contain discrete deer populations, efficient management must also depend on co-operation among those exploiting a common stock.

Incidence of ovulation before the onset of the rut and during pregnancy in red deer hinds

Abstract Ovaries were recovered from red deer hinds culled in South West and in 1973–1976 during late pregnancy/early lactation (13 November – 18 December), the non-breeding season (10 January – 23 February), the period just before the onset of the rut (16 March – 11 April), and early pregnancy (13 May – 1 June). The percentage of hinds with a corpus luteum just before the onset of the rut was low (16.3% of adult hinds). An accessory corpus luteum of pregnancy was found in 46.8% of hinds in early pregnancy and in 58.9% in late pregnancy/early lactation (the difference is not significant). The accessory corpus luteum was about half the size of the primary corpus luteum of pregnancy. It appeared that the accessory corpus luteum was formed early in the breeding season, and persisted until parturition.

The development and control of sexual behaviour in red deer

Despite obvious difficulties, the use of free-living red deer in the study of sexual differentiation is justified on account of their elaborate sexually dimorphic reproductive behaviour, their extreme seasonality in both sexes and the presence of conspicuous hormone dependant secondary sexual characteristics, especially antlers. Castration of free-living male red deer calves at birth on the Isle of Rhum, Scotland, did not eliminate the adult’s ability to distinguish oestrous hinds, follow and mount them and show flehmen. This was taken as being due to prenatal differentiation under the influence of testosterone. Nevertheless, administration of testosterone by subcutaneous implant to adult hinds elicited almost all components of rutting behaviour, suggesting that exposure to androgen early in life may not be essential for subsequent masculine behaviour. However immature stags (less than three years old) did not rut in response to testosterone implants and it seems likely that a maturation process is required for the display of sexual behaviour and that this process continues irrespective of the animal’s sex and hormone status. Administration of oestradiol-17p implants to adult castrated stags elicited full rutting activity including coitus, and currently oestradiol-170 implants are proving effective in stimulating rutting behaviour from an adult hind. These experiments suggest that, qualitatively, there is little difference between oestradiol-17P and testosterone in their effects on behaviour; the duration of the exposure is more critical than the nature of the steroid. This is in line with the hypothesis that testosterone may be aromatised to oestrogen in the central nervous system before being able to produce male behaviour. MOTHER-INFANT RELATIONSHIPS IN RED DEER