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PubMedDate not supplied

Seroprevalence of antibodies to Salmonella spp in semidomesticated reindeer in Norway, determined by enzyme-linked immunosorbent assay.

An indirect ELISA was developed as a possible tool to detect the seroprevalence of antibodies to Salmonella spp in semidomesticated reindeer. To cover a broad spectrum of serogroups a lipopolysaccharide mix of S. typhimurium and S. choleraesuis was used as antigen in this pilot study. Sera from 31 culture-negative reindeer with no clinical or historical evidence of salmonellosis were used as negative serum control. After immunisation with an inactivated S. typhimurium vaccine, pooled sera from 6 reindeer were used as positive serum control as no serum from naturally infected animals was available. A seroprevalence of 0.6% in 2000 clinically healthy, slaughter-reindeer from Norway was determined by using this ELISA. No more information on Salmonella in reindeer in Norway is known to the authors. This is the first ELISA established for indirect detection of Salmonella in reindeer.

Animals↗
PubMed1996

Experimental Toxoplasma gondii infection leading to fatal enteritis in reindeer (Rangifer tarandus).

Two, 50-60-kg yearling reindeer (Rangifer tarandus) were inoculated intraruminally with 5,000 (reindeer 1) or 50,000 (reindeer 2) oocysts of the ME-49 strain of Toxoplasma gondii. Both reindeer became ill day 4 postinoculation (p.i.). Reindeer 2 died because of acute enteritis day 9 p.i. Histologically, extensive necrosis and destruction of the intestinal mucosa were seen. Numerous T. gondii organisms were demonstrated immunohistochemically. Reindeer 1 was treated with sulfatrimethoprim for 2 days from day 9, recovered by day 16 p.i., and remained clinically normal until the last day of observation (day 707 p.i.). It developed high antibody titers to T. gondii between days 7 and 14 p.i.

Animals↗
PubMed2003

Effects of seasonal changes in food quality and food intake on the transport of sodium and butyrate across ruminal epithelium of reindeer.

Transport of 22Na and 14C-butyrate across the ruminal epithelium of captive reindeer fed a concentrate diet in summer (n=5) and in winter (n=5) and from free-ranging reindeer taken from summer (n=3) and winter pasture (n=5) was measured in vitro in Ussing chambers. Significant amounts of both Na+ and butyrate were transported across the isolated epithelium without any external driving force. The ruminal transport of Na+ and butyrate were interacting, as evidenced by both the observed amiloride-induced reduction of net butyrate-transport and by the positive correlation between net transport of butyrate and Na+. Amiloride also reduced the net transport of Na+ without significantly affecting the short-circuit current, indicating the presence of an apical Na+/H+ exchanger in the ruminal epithelium of reindeer. The captive reindeer increased the dry matter intake of a constant quality concentrate from winter to summer, but this neither affected their ruminal transport capacity nor their ruminal surface enlargement factor (SEF). Free-ranging reindeer increased their ruminal transport capacity for Na+ and butyrate from summer to winter but simultaneously reduced their ruminal SEF. The present data indicate that this food-induced increase in transport capacity was attributed to changes in the nutrient composition of the diet.

Amiloride↗
PubMed2005

Effects of natural winter pasture and commercial pellet on the ultrastructure of small intestinal epithelium in reindeer.

Segments of small intestine (duodenum, jejunum and ileum) from slaughtered reindeer (Rangifer tarandus tarandus) grazing natural winter pastures (n=3) and reindeer fed commercially available pellets (RF-80) in winter (n=5) were collected and immediately fixed in McDowell's fixative. Transmission electron microscopy was employed to investigate the ultrastructural features of the epithelium and lamina propria along the small intestine and to relate these to the different diets. Major differences in ultrastructural features were observed between the small intestinal enterocytes of reindeer fed the two diets. Enterocytes in reindeer fed the natural diet displayed a normal appearance with a dense cytoplasm and distinct microvilli. In contrast, reindeer fed the commercial diet showed damaged enterocytes amongst the normal cells. Abnormal changes included disintegration and loss of microvilli, cytoplasmic swelling, loss of membrane integrity and increases in the width of intercellular spaces, especially in the jejunum.

Animal Feed↗
PubMed2000

Reproduction in female reindeer.

Reindeer are either wild or kept under very extensive farming systems. They are seasonal breeders, with mating coinciding with the decreasing photoperiod in the autumn, and with calving in the spring. Little is known regarding the factors that influence reproduction in reindeer or of their reproductive physiology. Studies carried out to date have mainly focused on issues related to the population dynamics of wild populations and semi-domestic herds, and to a limited extent on the reproductive physiology of the female. Nor is much known about reproductive disorders and their medical treatment, or of the possibilities to manipulate or control reproduction by the use of hormones. Modern reproductive techniques such as artificial insemination and in vitro fertilisation, maturation and transfer of embryos have so far received scant attention.In the future, it is possible that reindeer under certain conditions might be kept in more intensive production systems. Limited access to high-quality winter pastures and increased demands for productivity have resulted in artificial feeding becoming a common practice in various reindeer herding areas in Scandinavia. In efforts to enhance the productivity of reindeer herds, attention has been focused on factors affecting reproduction in the female and survival of the offspring. Further knowledge on these issues seems necessary when developing strategies for optimalization of meat production in domestic herds and the harvesting of wild populations. This paper puts a broad focus on various aspects of reproduction, including factors influencing the fecundity of reproductively active females. In order to understand these effects it is important also to have a basic understanding of the reproductive physiology of these animals.

Animals↗
PubMed2003

Genetic variation in caribou and reindeer (Rangifer tarandus).

Genetic variation at seven microsatellite DNA loci was quantified in 19 herds of wild caribou and domestic reindeer (Rangifer tarandus) from North America, Scandinavia and Russia. There is an average of 2.0-6.6 alleles per locus and observed individual heterozygosity of 0.33-0.50 in most herds. A herd on Svalbard Island, Scandinavia, is an exception, with relatively few alleles and low heterozygosity. The Central Arctic, Western Arctic and Porcupine River caribou herds in Alaska have similar allele frequencies and comprise one breeding population. Domestic reindeer in Alaska originated from transplants from Siberia, Russia, more than 100 years ago. Reindeer in Alaska and Siberia have different allele frequencies at several loci, but a relatively low level of genetic differentiation. Wild caribou and domestic reindeer in Alaska have significantly different allele frequencies at the seven loci, indicating that gene flow between reindeer and caribou in Alaska has been limited.

Animals↗
PubMed2002

Microsatellite DNA evidence for genetic drift and philopatry in Svalbard reindeer.

Mainland populations of Arctic reindeer and caribou Rangifer tarandus often undergo extensive movements, whereas populations on islands tend to be isolated and sedentary. To characterize the genetic consequences of this difference, levels of genetic diversity and subdivision of Svalbard reindeer (R. t. platyrhynchus) from two adjacent areas on Nordenskjiöldland, Spitsbergen were estimated using data from up to 14 microsatellites. The mean number of alleles per locus in Svalbard reindeer was 2.4 and mean expected heterozygosity per locus was 0.36. The latter value was significantly lower than in Canadian caribou and Norwegian reindeer but higher than in some other cervid species. Large samples of females (n = 743) and small samples of males (n = 38) from two sites approximately 45 km apart showed genetic subdivision, which could be due to local population fluctuations or limited gene flow. To our knowledge, this is the first study to report significant differentiation at microsatellite loci in Rangifer at such short geographical distances. Neither population showed genetic evidence for recent population bottlenecks when loci unbiased with respect to heterozygosity were analysed. In contrast, false signals of a recent bottleneck were detected when loci upwardly biased with respect to heterozygosity were analysed. Thus, Svalbard reindeer appeared to conform to the paradigm of island populations made genetically depauperate by genetic drift.

Alleles↗
PubMedDate not supplied

[Occurence of Onchocerca tarsicola Bain and Schulz-Key, 1974, in reindeer (author's transl)].

Onchocerca tarsicola is recorded from reindeer (Rangifer tarandus L.). This parasite is originally described from red deer (Cervus elaphus L.). There are indications that reindeer may not be the primary host of O. tarsicola: 1. Reindeer is parasitized only by O, tarsicola whereas red deer, due to speciations, is carrying three related Onchocerca species from the same line. 2. O. tarsicola, usually found along tendons distal of the tarsal and carpal joints, is in reindeer frequently found at aberrant locations which is commonly observed in connection with "transfuga" parasites. 3. Heavy infestations of O. tarsicola in reindeer seem to have started in the late sixties and since then have become more and more extensive.

Animals↗
PubMed1975

Seasonal and nutritional effects on serum proteins and urea concentration in the reindeer (Rangifer tarandus tarandus L.).

1. The effects of seasonal conditions and nutrition on serum proteins and serum urea concentrations were studied in female reindeer and reindeer calves in Finland. With the exception of one group in winter, the reindeer were roaming wild in the forests. This one group was kept in captivity, out of doors, on a comparatively high nutritional plane. One group lived wild during the winter in very poor nutritional conditions. 2. A very clear seasonal variation in the serum protein and urea concentration was found. The serum protein concentration was low in late winter and increased rapidly during the summer, being high in the autumn. The serum urea concentration was also low in the winter and high in the summer. In the autumn, however, the serum urea concentration was again low. 3. Changes in the serum protein concentration were normally associated with the serum globulins. Only in the very poor-nutrition group did the albumin content decrease significantly. As a result of the large changes in the concentration of serum globulins, there were also considerable changes in the albumin: globulin ratio. 4. The serum protein concentration was much lower in the reindeer calves than in the adult reindeer. The concentration of globulins in particular was much lower than in the adults.

Animal Nutritional Physiological Phenomena↗
PubMed2002

The role of parasites in the dynamics of a reindeer population.

Even though theoretical models show that parasites may regulate host population densities, few empirical studies have given support to this hypothesis. We present experimental and observational evidence for a host-parasite interaction where the parasite has sufficient impact on host population dynamics for regulation to occur. During a six year study of the Svalbard reindeer and its parasitic gastrointestinal nematode Ostertagia gruehneri we found that anthelminthic treatment in April-May increased the probability of a reindeer having a calf in the next year, compared with untreated controls. However, treatment did not influence the over-winter survival of the reindeer. The annual variation in the degree to which parasites depressed fecundity was positively related to the abundance of O. gruehneri infection the previous October, which in turn was related to host density two years earlier. In addition to the treatment effect, there was a strong negative effect of winter precipitation on the probability of female reindeer having a calf. A simple matrix model was parameterized using estimates from our experimental and observational data. This model shows that the parasite-mediated effect on fecundity was sufficient to regulate reindeer densities around observed host densities.

Animal Diseases↗
PubMed1993

Seasonal changes in the adherent microflora of the rumen in high-arctic Svalbard reindeer.

Seasonal changes in bacterial colonization of the epithelial tissue were examined in the rumen of high-arctic Svalbard reindeer. Samples of tissue were collected from eight sites in the rumen of reindeer during summer and winter and bacterial colonization was examined using scanning and transmission electron microscopy. At two of these sites, colonization by adherent bacteria was estimated to cover approximately 30% of the ruminal epithelium in specimens collected from reindeer during summer. Bacteria at these sites resembled Ruminococcus sp. and were surrounded by large amounts of glycocalyx. In winter specimens, less than 10% of the epithelial surface was covered by adherent bacteria. Those bacteria that did colonize the epithelial surface were smaller and had virtually no glycocalyx on their surface. Bacteria attached to plant cell wall material in summer samples of reindeer ingesta contained large intracellular glycogen deposits, whereas feed particle-associated bacteria in ingesta collected in winter contained no intracellular glycogen. These data demonstrate that the ruminal bacterial population responds to seasonal changes in feed intake and quality. It is yet to be determined if these bacterial changes enhance the ability of Svalbard reindeer to survive in the hostile environment of the high Arctic.

Animals↗
PubMed1991

Brown fat-specific mitochondrial uncoupling protein in adipose tissues of newborn reindeer.

Reindeer inhabit a severe arctic or subarctic environment, with the young born in early spring under adverse weather conditions. The extreme northern climate imposes a major thermal challenge to the newborn, and in the present study we have examined fetal, neonatal, and young (from 2 wk before birth to 16 mo postpartum) semidomesticated reindeer from northern Finland for the presence of thermogenic brown adipose tissue. Adipose tissues were removed, mitochondria were prepared, and the proteins were separated by molecular weight and blotted onto nitrocellulose membranes. The membranes were then probed for the presence of the 32,000-relative molecular weight mitochondrial uncoupling protein (UCP) unique to brown fat by use of a rabbit anti-(ground squirrel UCP) serum. Immunoreactivity at the molecular weight characteristic of UCP was present in perirenal, abdominal, inter(pre)scapular, sternal, intralumbar, vertebral, tracheal, inguinal, and omental-mesenteral adipose tissues of newborn reindeer (0-2 days of age). No immunoreactivity was detected in coronary adipose tissue. UCP was found at high levels in interscapular and perirenal adipose tissues of fetal reindeer at 2 wk before birth. Although the protein was present during the first few days postpartum, little immunoreactivity was found at 1 mo of age, and none was evident by 2 mo. UCP and its mRNA were also apparent in perirenal adipose tissue of the newborn of another species of Cervidae, the red deer. It is concluded, on the basis of the immunologic identification of UCP, that most adipose tissues of newborn reindeer represent functional brown fat but that there is a subsequent conversion to white adipose tissue by the 2nd mo of life.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗
PubMed2004

Rumen ciliate protozoal fauna of reindeer in Inner Mongolia, China.

Rumen ciliate species and composition were surveyed on the reindeer kept in Inner Mongolia, China. As a result of survey, all the reindeer had the same 18 species of 8 genera of the ciliates in their rumen. Appearance of Entodinium parvum is the first record in this host species. Of the species detected, 15 species including Entodinium anteronucleatum, E. bicornutum, Enoploplastron confluens and Epidinium gigas which have been detected only from reindeer were common with those in the reindeer kept in the other areas, such as Alaska, Russia and Finland, indicating that every rumen ciliate faunae in reindeer has high similarity to each other, and suggesting that these hosts have been isolated from the other ruminants for long time and established characteristic ciliate fauna. The ciliate density was estimated as 1.1-2.5 x 10 (6)/ml, which value was fairly higher than those in domestic ruminants. Surface structures of characteristic species were observed by SEM.

Animals↗
PubMed1983

Ovarian characteristics and reproductive performance of reindeer, Rangifer tarandus.

A total of 301 female reindeer of various ages was shot on South Georgia in all months of the year to study seasonal and age-related changes in ovarian structures, and to undertake an intraspecific comparison with North American caribou. Ovarian weights and follicle numbers did not change in reindeer calves, and it is concluded that the South Georgia population do not attain physiological puberty in their first year. Compared with caribou, reindeer showed an earlier onset of ovarian activity, and had twice as many follicles greater than 2 mm diameter and secondary corpora lutea. The relationship between luteal scars and age was significant (P less than 0.001), despite an overcount of scars relative to age in some individuals, and indicated a fecundity rate of 0.93. The left and right ovaries of reindeer were equally productive. It remains unclear whether the differences in reproductive performance between reindeer and caribou are of genetic origin.

Aging↗
PubMed1999

Role of oestradiol in the regulation of the seasonal antler cycle in female reindeer, Rangifer tarandus.

Reindeer (or caribou), Rangifer tarandus, is the only extant species of deer in which females as well as males normally develop antlers that are cast and regrown each year. This study investigated the role of ovarian oestradiol in the regulation of the seasonal antler cycle in female reindeer. Ovariectomized Norwegian reindeer living outdoors in northern Norway (69 degrees N) were treated with continuous-release subcutaneous Silastic implants containing oestradiol, which maintained the blood concentrations of oestradiol within the physiological range for the mating season from June to October-November. The treatment with oestradiol induced the synchronized maturation of the antlers and rapid cleaning of the velvet-like skin in August-September in the ovariectomized reindeer, a pattern very similar to that observed in ovary-intact controls living under the same conditions. The removal of the steroid implant in October-November caused the premature casting of the antlers in early winter in two of five animals, while the remainder cast at the normal time in spring; this response was seen whether the animals had received one or two oestradiol implants in autumn. The antlers developed by the ovariectomized, oestradiol-treated females were significantly heavier and carried more branches than the ovariectomized animals without oestradiol replacement, and were marginally heavier than the antlers of intact controls. These results support the view that oestradiol is the biologically active steroid secreted by the ovary in intact female reindeers that induces the normal development of the antlers. Oestradiol stimulates the growth and mineralization of the antler bone, the cleaning of the velvet, and suppresses the casting of the hard antlers. This endocrine control ensures that the hard antlers, which function as weapons, are retained throughout the autumn and winter when the females are normally pregnant and when competition between females over food in the snow is most intense; hence there is a reproductive advantage to explain the evolution of antlers in females.

Animals↗
PubMed1990

Respiratory symptoms and ventilatory function among Finnish reindeer herders.

Prevalence of respiratory symptoms in relation to occupation and smoking habits were evaluated in 211 randomly selected male reindeer herders in Northern Finland. Clinical examination with skin prick tests (SPT) and spirometry was conducted in 23 local health centers. No significant differences could be determined in respiratory symptoms, smoking habits or ventilatory function between full-time reindeer herders and their controls. Positive SPT reactions to common allergens in reindeer herders were to some extent lower than expected. Only one test subject had positive SPT to reindeer epithelium. 35% were non-smokers, 32% smokers and 33% ex-smokers. Prevalence of chronic bronchitis was 10% in non-smokers and 28% in regular smokers, while the prevalence of cough was 18% and 23%, and that of the phlegm 10% and 34%, respectively. 14% had dyspnoea caused by cold air inhalation. In the age groups of 21-39 FVC and FEV1 increased by age in ex- and non-smokers but decreased in smokers. The mean FEV1% was lowest in regular smokers. Further studies are needed to establish the possible disadvantage of cold air to reindeer herder's working capacity.

Adult↗
PubMed1994

Microbiological contamination of reindeer carcass during slaughter.

Microbiological counts for 10 different sampling sites of 28 reindeer carcasses were studied in 3 reindeer slaughterhouses in Finland. On each carcass the hindshank, round, abdomen, flank, brisket, foreleg, shoulder, neck, foreback and back were sampled immediately after slaughter, using a non-destructive swabbing method. The overall mean bacterial count for 10 sampling sites of reindeer carcasses was 1.51 +/- 0.51 log10 cfu/cm. Statistically significant differences were detected between sampling sites. The back part of the reindeer carcass, i.e. hindshank, round, back and foreback, seemed to be relatively clean. The most contaminated parts were the foreleg, brisket and abdomen (2.05-2.95 log10 cfu/cm2); these could be used for monitoring the hygiene of the reindeer carcass after slaughter. Differences between the 3 slaughterhouses were detected for some sampling sites, which may be due to differences in slaughter techniques and hygiene.

Abattoirs↗
PubMed2004

Nutritional development of feeding strategies in arctic ruminants: digestive morphometry of reindeer, Rangifer tarandus, and muskoxen, Ovibos moschatus.

Reindeer have been classified as intermediate feeders and muskoxen as grazers based on differences in digestive morphology and consumption of fibrous plants. We hypothesized that the digestive morphology of young (< 2 months) reindeer and muskoxen anticipates transitions in diet and determines the feeding strategy of each species at adulthood. We compared structural morphology and rates of cell division in the rumen, abomasum, duodenum and liver of reindeer and muskoxen as neonates (1 day old), during the transition from milk to forage (30-60 days old) and in adults (> 7 yr). Development in utero provided the neonate with a functioning mucosa of the gastric abomasum and duodenal mucosa with high surface enlargement for digestion and absorption of concentrated milks. Transition to forage was preceded by changes in ruminal papillae structure that increased surface area and likely contributed to active fermentation by 60 days of age. The abomasum also increased in acid-secreting parietal cells during the transition to forage, which may enhance digestion of plant and microbial proteins. Rates of cell division also indicated a sustained differentiation of tissue structure during the transitional period. Young arctic ruminants expressed digestive structures that preceded full function, which indicated the ultimate feeding strategy of each species. For example, the rumen of young muskoxen had thick cornified epithelia and muscle layers that would provide ruminal mucosa with better protection from fibrous abrasion and enhance motility of bulky diets. Conversely, young reindeer had more complex papillary shapes in the rumen and more foliate villi in the duodenum, indicating a greater absorptive capacity of these structures than in muskoxen. Ontogenetic programs, therefore, play the primary role for digestive development of reindeer and muskoxen and determine the nutritional strategies of adults.

Journal Article↗