Red Deer Calves Research Articles

Relationship between Plasma and Saliva Urea Nitrogen Concentrations in New Zealand Red Deer Calves (Cervus elaphus).

Red deer (Cervus elaphus), like other ruminants, excrete approximately 70% of the nitrogen they ingest. Developing ways in which to reduce the rate of loss, such as manipulating the diet or selecting for efficiency of growth, requires close monitoring of the plasma urea N (PUN) concentration which, in turn, requires a simple, safe, and reliable method for collecting samples. Saliva is easier to collect than blood, but the relationship between the salivary urea N (SUN) and the PUN is not known for red deer. This was therefore evaluated in two strains of mixed-sex red deer calves (Cervus elaphus): a phenotype with a high seasonality of growth (H, n = 10) and a phenotype with a low seasonality of growth (L, n = 13). Both phenotypes were divided into two groups, which were each offered one of two forage-based diets ad libitum: a medium-quality diverse treatment and a low-quality perennial ryegrass-white clover treatment. Blood and saliva samples for the determination of the PUN and SUN were collected at dawn every four weeks for five months (April to September 2022). There was a strong linear relationship between the PUN and SUN in the pooled sample (R2 = 0.65, p < 0.001). The estimations of the PUN were significantly improved by adding diet and the date of sampling into the model (p < 0.001), but not phenotype (p > 0.75). SUN represents a reliable index of the PUN, and collecting saliva therefore represents a simple and inexpensive alternative to collecting blood samples in studies of nitrogen metabolism in red deer.

O45 Relationship between plasma and saliva urea nitrogen in New Zealand red deer calves (Cervus elaphus)

O45 Relationship between plasma and saliva urea nitrogen in New Zealand red deer calves (Cervus elaphus)

Water sprinkling as a tool for heat abatement in farmed Iberian red deer: Effects on calf growth and behaviour

Climatic models predict scenarios in which ambient temperature will continue increasing worldwide. Under these climatic conditions, fitness and animal welfare of many populations are expected to suffer, especially those that live in captive or semi-natural conditions, where opportunities of heat abatement are limited. We undertook an experimental design to assess the effect of heat abatement that water sprinkling might have on Iberian red deer calf growth and behaviour from birth to weaning (135 days). One group of ten mother-calf pairs lived on plots with water sprinkling (treatment) available during summer’s hottest time of the day, while the control group (nine mother-calf pairs) occupied plots with no available water sprinkling. Treatment and control groups were fed ad libitum and swapped between plots every seven days to minimise any plot effect. Body weight was monitored weekly and individual behaviour was recorded once or twice a week at mid-day. We observed that calves had showers under the sprinklers and wallowed in mud puddles. The results clearly indicated that calves of the treatment group showed a significant increase in body weight at weaning in comparison with the control group, with no differences between sexes (treatment: male = 56.5 kg, female = 50.3 kg; control: male = 50.3 kg, female = 46.5 kg). Mother weight and mother age effects were negligible on calf body weight at weaning. The heavier the mother the faster was the rate of growth of its offspring, irrespective of calf sex. The model indicated that although males grew significantly slower than female calves in the control group, males grew faster than females when exposed to the treatment. Calves of the treatment group spent less time drinking, less time in the shade, similar time eating and more time in motion than calves of the control group. There were no behavioural differences between calf sexes of treatment and control groups. The results indicate the importance of providing animals with opportunities of heat abatement in hot environments to improve animal growth and welfare in farmed Iberian red deer.

Heat stress reduces growth rate of red deer calf: Climate warming implications.

Climate models agree in predicting scenarios of global warming. In endothermic species heat stress takes place when they are upper their thermal neutral zone. Any physiological or behavioural mechanism to mitigate heat stress is at the cost of diverting energy from other physiological functions, with negative repercussions for individual fitness. Tolerance to heat stress differs between species, age classes and sexes, those with the highest metabolic rates being the most sensitive to stressing thermal environments. This is especially important during the first months of life, when most growth takes place. Red deer (Cervus elaphus) is supposedly well adapted to a wide range of thermal environments, based on its worldwide distribution range, but little is known about the direct effect that heat stress may have on calf growth. We assessed the effect that heat stress, measured by heat stress indices and physical environment variables (air temperature, relative air humidity, wind speed and solar radiation), have on calf and mother body weights from calf´s birth to weaning. We used 9265 longitudinal weekly body weight records of calf and mother across 19 years in captive Iberian red deer. We hypothesised that (i) heat stress in hot environments has a negative effect on calf growth, especially in males, as they are more energetically demanding to produce than females; and that (ii) the body weight of the mother through lactation should be negatively affected by heat stress. Our results supported hypothesis (i) but not so clearly hypothesis (ii). By weaning (day 143) calves growing under low heat stress environment grew up to 1.2 kg heavier than those growing in high heat stress environment, and males were more affected by heat stress than females. The results have implications in animal welfare, geographical clines in body size and adaptation to climate change.

In Vitro Culture of Deer Embryos.

In vitro embryo production of deer species has the potential to increase valuable traits for the agricultural sector, and from a conservation perspective, it is a propagation tool which can improve genetic diversity in small captive populations. In vitro embryo production is a multistep process consisting of oocyte maturation, fertilization, and embryo culture. These techniques provide the backbone for more advanced assisted reproductive technologies such as intracytoplasmic sperm injection (ICSI), somatic cell nuclear transfer (SCNT), a source of embryonic stem cells, and embryos for gene editing. In vitro-produced embryos are a readily available resource for comparative embryology studies and a functional assay to assess oocyte competence and evaluate in vitro embryo requirements during culture. A semidefined fertilization and culture medium system, deer synthetic oviduct fluid (DSOF), has been formulated based on deer oviduct fluid. Red deer calves (Cervus elaphus) and Thamin Eld's deer fawn (Rucervus eldii thamin) have been produced after the transfer of in vitro embryos (IVF and SCNT) grown in DSOF culture. Here we describe the in vitro method of maturation, fertilization, and embryo culture for deer species.

Low Copper Levels Associated with Low Carcass Weight in Wild Red Deer ( Cervus elaphus ) in Norway.

Copper (Cu) deficiency is associated with several disease syndromes, including poor growth, in farmed red deer ( Cervus elaphus ), but little is known of the consequences of low Cu levels in free-ranging populations. Low hepatic Cu levels have been documented in several wild red deer populations along the west coast of Norway, with the lowest values found on the island of Hitra. We studied the relationship between liver Cu concentration and slaughter weight in 63 red deer calves and 69 yearlings shot on Hitra during the autumn hunting season of 2009. Less than half of each age class had adequate Cu levels (>20 μg/g dry weight) and 14% of the calves and 28% of the yearlings had levels indicating deficiency (<13 μg/g). For yearlings, but not calves, there was a significant increase in slaughter weight with increasing hepatic Cu level. The differences between yearlings and calves could be linked to differences in physiologic Cu status of the two age classes, in that red deer calves are born with much higher levels of hepatic Cu than are their mothers. Our data demonstrate an association between low levels of Cu and reduced growth rate in a free-ranging cervid population.

The power of oral and nasal calls to discriminate individual mothers and offspring in red deer, Cervus elaphus.

BackgroundIn most species, acoustical cues are crucial for mother-offspring recognition. Studies of a few species of ungulates showed that potential for individual recognition may differ between nasal and oral contact calls.ResultsVocalizations of 28 hinds and 31 calves of farmed Iberian red deer (Cervus elaphus hispanicus) were examined with discriminant function analyses (DFA) to determine whether acoustic structure of their oral and nasal contact calls encodes information about the caller’s identity. Contact calls were elicited by brief separation of individually identified animals by a distance over 10 m or by a bar fence. Both oral and nasal calls of both hinds and calves showed high potential to discriminate individuals. In hinds, individuality was significantly higher in the oral than in the nasal calls, whereas in calves, individuality was equally well expressed in both oral and nasal calls. For calves, the maximum fundamental frequency was higher and the duration was longer in oral calls than in nasal calls. For hinds, the maximum fundamental frequency and the duration were indistinguishable between oral and nasal calls. Compared to the pooled sample of oral and nasal calls, separate oral or nasal call samples provided better classifying accuracy to individual in either hinds or calves. Nevertheless, in both hinds and calves, even in the pooled sample of oral and nasal calls, the degree of individual identity was 2–3 times greater than expected by chance. For hinds that provided calls in both years, cross-validation of calls collected in 2012 with discriminant functions created with calls from 2011 showed a strong decrease of classifying accuracy to individual.ConclusionsThese results suggest different potentials of nasal and oral calls to allow the discrimination of individuals among hinds, but not among red deer calves. The high potential of individual recognition even with the pooled sample of oral and nasal calls allows mother and young to remember only one set of acoustic variables for mutual vocal recognition. Poor between-year stability of individual characteristics of hind oral and nasal calls would require updating keys to individual recognition each calving season.Electronic supplementary materialThe online version of this article (doi:10.1186/s12983-014-0094-5) contains supplementary material, which is available to authorized users.

Heritability and cross-sex genetic correlations of early-life circulating testosterone levels in a wild mammal.

Testosterone is an important hormone that has been shown to have sex-specific links to fitness in numerous species. Although testosterone concentrations vary substantially between individuals in a population, little is known about its heritable genetic basis or between-sex genetic correlations that determine its evolutionary potential. We found circulating neonatal testosterone levels to be both heritable (0.160 ± 0.064 s.e.) and correlated between the sexes (0.942 ± 0.648 s.e.) in wild red deer calves (Cervus elaphus). This may have important evolutionary implications if, as in adults, the sexes have divergent optima for circulating testosterone levels.

Hind genotype influences on lactation and calf growth in farmed red deer (Cervus elaphus)

Multiparous red deer (Cervus elaphus scoticus) hinds (n=18) were artificially inseminated with semen from a red deer stag (n=8) or wapiti bull (C.e. nelsoni) (n=10) to produce red deer or F1 crossbred (C.e. scoticus×C.e. nelsoni) calves. A further seven wapiti×red deer (F1) hinds were artificially inseminated with semen from an unrelated F1 stag to test the hypotheses that (1) crossbred hinds rearing crossbred calves will produce more milk to support calf growth than red deer hinds rearing crossbred calves, and (2) the extra lactation demand of crossbred calves will exert a more detrimental effect on red deer hind live weight and body condition than would occur if the dam was a crossbred hind. Hinds and calves were grazed on ryegrass and white clover pastures and supplemented with pasture silage and barley grain when pasture supply was inadequate. Calves were left with their mothers until approximately 240 days of age. Mean body condition score (BCS) was lower in F1 hinds rearing F2 calves during late lactation (days 150 to 240, P<0.05) than red deer hinds rearing either red deer or F1 calves. F1 calves grew significantly faster than red deer calves and were heavier at all ages, while F2 calves were intermediate. Milk intake of both F1 and F2 calves was higher than red deer calves until day 76 of lactation (P>0.05), but similar thereafter. Male calves had a higher milk intake than female calves at 20 days of age only (P=0.004). The average hind pasture intake was greatest in F1 hinds rearing F2 calves, intermediate in red deer hinds rearing F1 calves and lowest in red deer hinds rearing red deer calves (P=0.038). Total milk output for the lactation increased by approximately 14.6kg/kg average calf live weight at weaning for both F1 hinds rearing F2 calves (P=0.008) and red deer hinds rearing red deer calves (P=0.072), suggesting that calf demand rather than hind liveweight was the key determinant of lactation performance. This was not the case for red deer hinds rearing F1 calves suggesting that there is an upper limit to lactation output depending on hind size. These results do not support the hypothesis that a crossbred hind rearing a crossbred calf will produce more milk than a red deer hind rearing a crossbred calf and provides evidence that the milk production of the hind is primarily driven by milk demand of the calf but has an upper limit depending on the size of the hind. The second hypothesis was not supported as F1 hinds rearing F2 calves exhibited greater loss of body condition score relative to the red deer hinds rearing either red deer or F1 calves in this study. This suggests that the additional energetic demands on a hind from feeding an F1 calf may be met with adequate nutrition.

Sex and age-class differences in calls of Iberian red deer during the rut: reversed sex dimorphism of pitch and contrasting roars from farmed and wild stags

Stag rutting calls differ among subspecies of red deer Cervus elaphus. Studying sex-, age-, and subspecies-related vocal variation may highlight the forces driving this evolution. This study presents the first bioacoustical comparison of oral calls produced during the rut by Iberian red deer Cervus elaphus hispanicus stags, hinds and calves and compares the acoustics of nasal and oral calls of hinds and calves. Also, it provides the first comparison of rutting roars between farmed and wild stags. Call maximum and mean fundamental frequencies (f0max and f0mean) were higher in farmed than in wild stags. Moreover, hinds had lower f0max and f0mean compared with both farmed and wild stags. The call minimum fundamental frequency (f0min) was indistinguishable between all groups of adults, irrespective of sex, farming and nasal versus oral vocal emission. In calves, but not in hinds, oral calls had higher f0max and f0mean compared with nasal calls. The higher fundamental frequencies in farmed as compared with wild stags may have resulted from emotional arousal due to human presence at recordings or from the higher body conditions of stags reared under a farm. The comparison of our results with previously published data on various subspecies of red deer suggests that there are different pathways of vocal ontogeny in eastern and western branches of Cervus elaphus and that the acoustics of stag and hind calls are more similar within the various subspecies than they are among the subspecies.

Influence of calf genotype on dam lactation and calf growth in farmed red deer (Cervus elaphus)

Multiparous red deer (Cervus elaphus scoticus) hinds (n=17) were either mated to a red deer stag or artificially inseminated with semen from a wapiti bull (C.e. nelsoni) to produce red deer or F1 crossbred (C.e. scoticus × C.e. nelsoni) calves to test the hypotheses that (1) red deer hinds rearing crossbred calves will produce significantly more milk to support calf growth than hinds rearing red deer calves, and (2) hind live weight and body condition may suffer as a result. Hinds and calves were grazed on ryegrass and white clover pastures and supplemented with pasture silage and barley grain when pasture supply was inadequate. Calves were left with their mothers until 9–10 months of age when lactation had terminated naturally. Mean body condition score (BCS) loss was greater in hinds rearing F1 calves than in hinds rearing red calves in the period from late gestation to mid-lactation (September–March, P<0.05). F1 calves grew significantly faster than red deer calves and were heavier at all ages. From February onwards there was a consistent decline in milk intake, and by the latest measurement (22 July) milk production was negligible, and most hinds had ceased lactating. Milk intake by the F1 calves was significantly greater until day 114, after which the measured milk intake was not significantly different. Pasture intake of the F1 calves was significantly greater at day 114 but not at other times (P<0.05). The average hind pasture intake was also not significantly affected by calf genotype when adjusted for post calving hind live weight. The results support the hypothesis that a red deer hind rearing an F1 calf produces significantly more milk than a hind rearing a red deer calf, suggesting that the growth of a red deer calf is limited by its milk demand rather than milk supply by the hind. The study also supported the second hypothesis. Hinds rearing F1 calves exhibited greater losses of body condition score relative to the hinds rearing red deer calves, indicating that the hinds rearing F1 calves were in a greater negative energy balance that hinds rearing red deer calves. This highlights the additional energetic demands on a hind from feeding an F1 calf and in a farmed context the need to ensure that adequate nutrition is provided.

Gastrointestinal tract development in red deer (Cervus elaphus) calves from 1 to 12 months of age

This study provides a detailed description of the development of the gastrointestinal tract (GIT) of farmed red deer (Cervus elaphus) calves over the first 12 months of age. GIT development was measured using a combination of computerised tomography (CT) scanning and traditional slaughter plus dissection techniques. Red deer calves of a known birth date were randomly assigned to two treatment groups. A group of five animals were repeatedly CT scanned at 31, 63, 92, 135, 207, 275 and 351 days of age to identify GIT organs and determine their volume. From a group of 20 animals, subsets of four individuals were also scanned at corresponding ages (except 135 days of age). They were immediately euthanised and dissected after CT scanning to compare CT-scanned results with actual anatomical measurements. Individual organ weights were compared with their respective organ volumes determined by CT scanning and were found to have a strong, positive relationship. The combined rumen and reticulum (RR) CT-scanned volume was compared with its volume determined by the water-displacement technique and this also showed good correlation between the two techniques (R = 0.92). The allometric growth rates of organs, relative to animal live weight gains, in descending order, were the rumen, omasum, reticulum, abomasum, caecum blind sac, kidneys, spleen and liver. The red deer GIT was continuing to grow and develop when the last measurement was taken at 351 days of age. The greatest growth of the RR, when expressed in terms of empty weight, was between 31 and 92 days of age. Compared with sheep and cattle, it appears that the red deer have a similar or greater rate of RR development up until approximately 60 to 90 days of age; however, the final increments of GIT maturity in deer may take longer to complete, with the empty weight of the RR gaining 7.5 g/day between 275 and 351 days of age. CT scanning was validated in this study as a viable technique to follow GIT development in the same animals over time, and it provided novel information on allometric organ growth. The success of CT scanning highlights the potential future use of diagnostic imaging for GIT development studies.

Pre-orbital gland opening: Part of sucking behavior in red deer (Cervus elaphus) calves1

Opening of the pre-orbital gland in red deer (Cervus elaphus) was previously found to be associated with feeding and negatively associated with achieving satiety in bottle-reared red deer calves. We speculated that this acted as a signal from a calf to the mother that it was hungry. Thus, we focused on a possible association between the pre-orbital gland opening and the sucking behavior in red deer calves. We recorded 63 sucking attempts and 150 sucking bouts within a stable social group of 24 farmed red deer females with 19 calves ages 16 to 90 d. The probability of the pre-orbital gland opening or remaining open during a sucking bout rapidly decreased with the on-going sucking phase (P < 0.001), and it was less after than during a sucking attempt (P < 0.03). The proportion of open pre-orbital glands at the end of sucking depended on whether the nursing female (27.85%) or the calf (0%, P < 0.01) terminated the sucking bout. The open pre-orbital gland of the calf after the sucking bout significantly predicted a subsequent sucking attempt (P < 0.001). The probability of open pre-orbital gland was not significantly affected by the age of the calf, sex or birth weight, or age of the nursing female. In conclusion, our study provides evidence that the opening of the pre-orbital gland is one of the general patterns of calf sucking behavior, specifically that it reflects the level of satisfying calf needs.

Pre-orbital gland opening in farmed red deer (Cervus elaphus) during stressful handling1

Stressful manipulation by humans has been previously shown to result in opening the pre-orbital gland of the newborn red deer. We hypothesized that exposure of red deer to stressful handling would result in opening the pre-orbital gland. Further, we tested the potential factors associated with pre-orbital opening, including season, sex, age and struggling behavior. Pre-orbital gland status was observed in 76 red deer (48 males, 28 females) during 281 handling events with the animal isolated and fixed in a mechanical restraint cradle (crush) within 3 consecutive years. The deer age ranged from 1 to 5 yr in males, and from 1 to 11 yr in females at the beginning of observations. The proportion of handling events with an open gland was considerably greater during than before handling (27.76 vs. 0%, respectively, P < 0.001). The deer that struggled or stiffened revealed 2-fold greater incidence of pre-orbital opening (P < 0.01), regardless of sex. Thus, pre-orbital opening seemed to accompany the behaviors that have been found to be related to acute stress. The probability that the animal opens its pre-orbitals during handling sharply increased at the beginning of the rut (mating season, P < 0.01). Deer that threatened the handler (10% out of 215 observations) opened their pre-orbitals 30 times more often than nonthreatening ones. These effects indicate that other motivations are likely involved in the opening of pre-orbitals, in addition to the perception of a stressful event. Incidence of pre-orbital opening decreased with age in both sexes (P < 0.05) across 3 consecutive yr of observations, which suggests habituation to repeated handling. Sex of the animal did not influence the probability of pre-orbital opening. We found significant variability in pre-orbital opening across the individuals (P < 0.001). In conclusion, we confirmed an association between opening of the pre-orbital gland and stressful handling in sub-adult and adult red deer, although repeated human handling did not elicit such incidence of pre-orbital opening as found in newborn red deer calves. Our results support multifactorial origins of pre-orbital opening and prompt the necessity of further research to distinguish between different motivations that might have been involved in opening of pre-orbitals.

Pre-weaning growth of red deer calves is not determined by ability of hinds to produce milk

Three experiments were carried out to determine whether growth of suckling red deer calves is determined by the potential of their mothers to produce milk. In the first experiment red deer hinds (n = 10, calves 6 weeks old) were treated either with bovine somatotrophin (bST, 54 mg s.c. injected every 2 weeks for 8 weeks then 108 mg every 2 weeks for a further 8 weeks) or saline. There was no effect of bST treatment on calf or hind liveweight, calf liveweight gain or body condition score of hinds. The second experiment used red and red-wapiti crossbred deer calves (n = 8–11) suckled by red deer dams that had been treated with bST or had received excipient only for 12 weeks from when the calves were 5 weeks old. Calf liveweight was affected by genotype (wapiti-red crossbreds were heavier than their red counterparts) but there was no effect of bST treatment of the hinds on calf growth in either of the genotypes. Although bST treatment of the suckled hinds elevated their plasma insulin-like growth factor-1 concentration it had no effect on milk yield. A third experiment ruled out the possibility that bST ingested by calves in milk from treated hinds would have had any influence on growth of calves in the other experiments. From these results it is concluded that the inherent demand from suckling calves, rather than the ability of adequately nourished hinds to produce milk, determines growth rate of red deer calves from birth to weaning.

Bilateral Microphthalmia and Aphakia Associated with Multiple Eye Abnormalities in a Free-Living European Red Deer Calf (&lt;i&gt;Cervus elaphus&lt;/i&gt;)

A free-living European red deer calf (Cervus elaphus) was euthanized due to bilateral microphthalmia. Lens was missing, replaced by proliferating squamous epithelial cells; hyperplastic squamous cells, sebaceous and mucinous glands were observed within the cornea with the characteristics of inclusion cyst. Findings were consistent with congenital microphthalmia/aphakia, with multiple eye abnormalities.

Energy and protein as nutritional drivers of lactation and calf growth of farmed red deer

Red deer calf growth rates from birth to 12weeks of age seldom exceed 450g/day on the best quality ryegrass/white clover pastures offered to lactating hinds over summer. However, the genetic potential for calf growth exceeds that observed on most farms. The metabolisable energy (ME) content of feed is traditionally used as the measure of feed quality for lactating hinds. The present study investigated the possibility that protein, rather than energy, content of forage may be a more important determinant of hind lactation performance and calf growth for red deer. A total of 16 mature red deer hinds pregnant to a red deer stag were calved indoors in individual pens. For the duration of their 12-week lactation they were each given daily ad libitum offers of pellet ration (+5% by weight of lucerne hay) that contained either low energy/low protein (LE/LP), low energy/high protein (LE/HP), high energy/low protein (HE/LP) or high energy/high protein (HE/HP) (i.e. n=4 per treatment). Calves and hinds were weighed weekly during the study. The mean dry matter intake of hinds was significantly higher (by about 35–40%) for hinds receiving low energy rations (i.e. LE/LP and LE/HP groups) irrespective of protein content. This resulted in all treatment groups exhibiting the same average energy intake, providing strong evidence for ‘energy balancing’ of feed intake (i.e. intake compensates for energy content of feed). As a consequence of “energy balancing” there was substantial between-treatment group variance in mean protein intake (400–1200gcrudeprotein/hind/day). However, there was no relationship between protein intake and calf growth performance. In contrast, regression analysis of individual hind variation in energy intake and calf growth revealed that energy intake during lactation was a major determinant of calf growth performance. Overall, calf growth during the 10–12weeks of lactation was lower than expected within the indoor system, and probably reflects a low intake of pellets by the calves themselves. The results of the study support the concepts of energy maximisation and do not support the central hypothesis of potential protein deficiency. Data from this experiment suggest that 400g/day crude protein intake is adequate for lactation in red deer hinds.

Inbreeding depression in red deer calves

BackgroundUnderstanding the fitness consequences of inbreeding is of major importance for evolutionary and conservation biology. However, there are few studies using pedigree-based estimates of inbreeding or investigating the influence of environment and age variation on inbreeding depression in natural populations. Here we investigated the consequences of variation in inbreeding coefficient for three juvenile traits, birth date, birth weight and first year survival, in a wild population of red deer, considering both calf and mother's inbreeding coefficient. We also tested whether inbreeding depression varied with environmental conditions and maternal age.ResultsWe detected non-zero inbreeding coefficients for 22% of individuals with both parents and at least one grandparent known (increasing to 42% if the dataset was restricted to those with four known grandparents). Inbreeding depression was evident for birth weight and first year survival but not for birth date: the first year survival of offspring with an inbreeding coefficient of 0.25 was reduced by 77% compared to offspring with an inbreeding coefficient of zero. However, it was independent of measures of environmental variation and maternal age. The effect of inbreeding on birth weight appeared to be driven by highly inbred individuals (F = 0.25). On the other hand first year survival showed strong inbreeding depression that was not solely driven by individuals with the highest inbreeding coefficients, corresponding to an estimate of 4.35 lethal equivalents.ConclusionsThese results represent a rare demonstration of inbreeding depression using pedigree-based estimates in a wild mammal population and highlight the potential strength of effects on key components of fitness.

Effects of ad libitum mineral consumption in Iberian red deer hinds and calves

Minerals are essential nutrients for ungulates because they cannot be synthesised. Lactation is the most mineral-demanding stage for hinds, whereas for calves both the pre- and post-weaning growth periods are important for bone formation, among other processes. Because both physiological effort and hot Mediterranean climate may increase mineral needs even in a situation under an ad libitum high plane of nutrition, we examined the effects of free-choice, single-mineral consumption in red deer hinds and their calves during lactation, and in the calves, from 18 to 56 weeks after lactation. Group M had permanent access to minerals, the control group had no access, whereas the LM and PLM groups of calves had access to minerals only during lactation or after lactation, respectively. Hinds with or without mineral supplements during lactation did not show differences in weight or body condition, neither did female calves of any group during or after lactation. However, after controlling the effect of year, LM male calves achieved greater weight gains during the post-lactation experiment, whereas the PLM and M groups showed negative results in weight at the end of the post-lactation experiment and age of antler growth initiation, respectively. The LM group also achieved higher scores in all the studied first antler variables (length, weight, burr perimeter, and perimeter in the middle of the antler) after controlling the effects of weight and year. The results thus suggest that, under ad libitum access to high-quality food, mineral supplementation is only positive during lactation. However, it cannot be ruled out that minerals may be beneficial in other stages in free-ranging deer.

Congenital nutritional myodegeneration (white muscle disease) in a red deer (Cervus elaphus) calf

CASE HISTORY A 5-day-old red deer calf was submitted with tachypnoea and dyspnoea, and was reluctant to move. CLINICAL FINDINGS: Muscular damage was established via elevated creatinine phosphokinase (CPK) activities (5,000 U/L), while concentrations of Se in whole blood were low (24.8 nmol/L). The animal died despite treatment with penicillin-streptomycin and 0.1 mg/kg Se/vitamin E administered by S/C injection. DIAGNOSIS: Necropsy and histological examination of cardiac and skeletal muscle confirmed the presumptive diagnosis of congenital white muscle disease (WMD). Prophylactic administration of a Se/vitamin E commercial preparation (as above) to another calf born in the same herd one month later was associated with good health and apparently normal growth and development. CLINICAL RELEVANCE: Congenital WMD due to Se deficiency can be fatal in red deer calves. However, prophylactic administration of Se and vitamin E to neonatal calves may be beneficial for neonatal red deer calves.