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1.
Anim Reprod Sci ; 235: 106890, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34847527

RESUMO

Interest in the use of assisted reproductive technology in reindeer husbandry has gradually increased during the last decades. This article reviews Western and Russian literature on reindeer semen collection, semen cryopreservation and artificial insemination. In addition, literature on the synchronisation of the stage of reindeer oestrous cycle among females, recovery of in vivo embryos, embryo transfer, the production of in vitro-produced embryos and pregnancy diagnosis is reviewed.


Assuntos
Prenhez , Rena , Técnicas de Reprodução Assistida/veterinária , Animais , Criopreservação/veterinária , Transferência Embrionária/veterinária , Ciclo Estral , Feminino , Inseminação Artificial/veterinária , Masculino , Gravidez , Sêmen , Manejo de Espécimes/veterinária
2.
Anim Reprod Sci ; 227: 106722, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33621844

RESUMO

The present review provides a comprehensive assessment on the basic aspects of the reproduction of the Rangifer male with a special focus on pubertal development, and the seasonal dynamics of gametogenesis, androgenesis, antler cycle and other physiological and behavioural characteristics of the rutting male. A greater understanding of the reproductive physiology of the males is needed to improve existing management strategies of semi-domestic stocks in the changing climate and to develop species-specific assisted reproductive technologies for improving the in situ and ex situ conservation programs to preserve endangered subspecies as well as to facilitate the transfer of genetic resources between fragmented wild or semi-domestic populations.


Assuntos
Rena/fisiologia , Reprodução/fisiologia , Animais , Masculino
3.
Animal ; 15(1): 100058, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33516010

RESUMO

Pasture-based and small-scale livestock farming systems are the main source of livelihood in the mountain primary sector, ensuring socioeconomic sustainability and biodiversity in rural communities throughout Europe and beyond. Mountain livestock farming (MLF) has attracted substantial research efforts from a wide variety of scientific communities worldwide. In this study, the use of text mining and topic modelling analysis drew a detailed picture of the main research topics dealing with MLF and their trends over the last four decades. The final data corpus used for the analysis counted 2 679 documents, of which 92% were peer-reviewed scientific publications. The number of scientific outputs in MLF doubled every 10 years since 1980. Text mining found that milk, goat and sheep were the terms with the highest weighed frequency in the data corpus. Ten meaningful topics were identified by topic analysis: T1-Livestock management and vegetation dynamics; T2-Animal health and epidemiology; T3-Methodological studies on cattle; T4-Production system and sustainability; T5-Methodological studies; T6-Wildlife and conservation studies; T7-Reproduction and performance; T8-Dairy/meat production and quality; T9-Land use and its change and T10-Genetic/genomic studies. A hierarchical clustering analysis was performed to explore the interrelationships among topics, and three main clusters were identified: the first focused on sustainability, conservation and socioeconomic aspects (T4; T6 and T9), the second was related to food production and quality (T7 and T8) and the last one considered methodological studies on mountain flora and fauna (T1; T2; T3; T5 and T10). The 10 topics identified represent a useful and a starting source of information for further and more detailed analysis (e.g. systematic review) of specific research or geographical areas. A truly holistic and interdisciplinary research approach is needed to identify drivers of change and to understand current and future challenges faced by livestock farming in mountain areas.


Assuntos
Agricultura , Gado , Animais , Bovinos , Mineração de Dados , Europa (Continente) , Fazendas , Ovinos
4.
PLoS One ; 14(5): e0216223, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31071155

RESUMO

Satellite telemetry is an increasingly utilized technology in wildlife research, and current devices can track individual animal movements at unprecedented spatial and temporal resolutions. However, as we enter the golden age of satellite telemetry, we need an in-depth understanding of the main technological, species-specific and environmental factors that determine the success and failure of satellite tracking devices across species and habitats. Here, we assess the relative influence of such factors on the ability of satellite telemetry units to provide the expected amount and quality of data by analyzing data from over 3,000 devices deployed on 62 terrestrial species in 167 projects worldwide. We evaluate the success rate in obtaining GPS fixes as well as in transferring these fixes to the user and we evaluate failure rates. Average fix success and data transfer rates were high and were generally better predicted by species and unit characteristics, while environmental characteristics influenced the variability of performance. However, 48% of the unit deployments ended prematurely, half of them due to technical failure. Nonetheless, this study shows that the performance of satellite telemetry applications has shown improvements over time, and based on our findings, we provide further recommendations for both users and manufacturers.


Assuntos
Animais Selvagens/fisiologia , Ecossistema , Monitoramento Ambiental , Sistemas de Informação Geográfica , Astronave , Telemetria , Animais
5.
Artigo em Inglês | MEDLINE | ID: mdl-16325441

RESUMO

Plasma total protein (TP), albumin (ALB) and globulin (GLOB) concentrations and albumin/globulin ratio (A/G) were analysed from blood samples collected from free-ranging reindeer (Rangifer tarandus tarandus) herds at varying times of year. The same parameters were followed in nine captive reindeer with varying protein and energy intake. Variation in the blood constituents of free-ranging reindeer was analysed in relation to different extrinsic and intrinsic factors and compared to findings from captive animals, allowing the analysis of effects of protein and energy intake. There was large overall variation in TP, ALB, GLOB and A/G ratio in the free-ranging animals, ranging between 36-110 g/L, 18-59 g/L, 17-59 g/L and 0.5-2.1. The variation between months and years was significant for all variables except the A/G ratio, where no year effect was noted. Increase in live body mass was associated with a small significant increase and pregnancy with a small significant decrease in all dependent variables, except for the A/G ratio. Age did not have a significant effect on any of the blood constituents when body mass was included in the same model. In captive animals, feeding lichens with low protein content was related to a significant decline in TP, ALB and GLOB, but not in the A/G ratio, whereas feeding commercial ration increased plasma TP, ALB and GLOB significantly. Extrinsic factors such as season and year explained majority of variation in the blood constituents of free-ranging reindeer, whereas body mass, pregnancy and age had only a minor influence. It is concluded that plasma TP and ALB, and to a lesser extent GLOB and A/G ratio may serve as nutritional biomarkers of reindeer.


Assuntos
Proteínas Sanguíneas/metabolismo , Dieta , Rena/fisiologia , Albumina Sérica/metabolismo , Soroglobulinas/metabolismo , Animais , Proteínas Sanguíneas/análise , Feminino , Análise de Regressão , Estações do Ano , Albumina Sérica/análise , Soroglobulinas/análise , Fatores de Tempo
6.
Radiat Environ Biophys ; 44(2): 107-17, 2005 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-16180038

RESUMO

Sr-85 and (134)Cs in aqueous solution of the chlorides were administered daily to four pregnant reindeer during the last part of gestation. Radionuclide concentrations were determined in calves sacrificed at birth, and secretion of the nuclides was measured in milk. Although the gastrointestinal absorption of (85)Sr was low, an apparently higher transfer of the absorbed fraction of (85)Sr than (134)Cs from the mother to the foetus led to similar accumulation of (85)Sr and (134)Cs in foetuses. At birth 1.4-1.6 and 1.5-2.5% of the total administered activities of (85)Sr and (134)Cs, respectively, were present in the calves' bodies. Transfer coefficients (F (m)) for (85)Sr and (134)Cs from feed to milk were estimated at 0.0218+/-0.0026 and 0.185+/-0.025 day kg(-1), respectively, and the observed ratio (OR(milk-diet)) for (85)Sr was 0.124+/-0.037. Transfer of radiostrontium to reindeer milk was in agreement with previously reported relationships between Ca intake and radiostrontium transfer in ruminants. These relationships suggest that the transfer of radiostrontium to foetuses and milk of free-ranging reindeer can be 3-4 times higher than observed in this experiment (due to lower Ca intake with natural forage), but the transfer to milk will not be as high as that of ionic (134)Cs. The concentrations of (85)Sr in milk suggested that the does mobilized skeletal stores of Ca and (85)Sr for milk production, although the diet appeared to satisfy the Ca requirements. In reindeer with radiostrontium intake during the whole year, radiostrontium concentrations in milk will therefore be higher than indicated by the F (m) value observed in our study. No differences in half-times for (85)Sr and (134)Cs secretion in milk were detected. Both nuclides were secreted with short- and long-term half-times of 1-2 and 12-19 days, respectively. For (85)Sr, 80-90% of the activity was excreted with the short half-time, whereas the corresponding value for (134)Cs was 30-50%.


Assuntos
Radioisótopos de Césio/farmacocinética , Contaminação Radioativa de Alimentos , Rena/metabolismo , Radioisótopos de Estrôncio/farmacocinética , Animais , Animais Recém-Nascidos , Fenômenos Biofísicos , Biofísica , Cálcio da Dieta/administração & dosagem , Dieta , Feminino , Feto/metabolismo , Contaminação Radioativa de Alimentos/análise , Humanos , Troca Materno-Fetal , Leite/metabolismo , Gravidez
7.
Theriogenology ; 63(6): 1775-88, 2005 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-15763117

RESUMO

The endocrinology was studied throughout pregnancy in reindeer (Rangifer tarandus tarandus) located in Oulu, Finland (65 degrees N, 25 degrees E) with 13 captive, semi domestic adult females. Blood samples were analyzed for plasma progesterone (P4), estradiol (E2) and estrone sulphate (E1SO4), 15-ketodihydro-PGF2alpha (PG-metabolite) and pregnancy associated glycoproteins (PAG). The mean plasma P4 concentration peaked twice during gestation: at around 24 and three weeks prior to calving. In pregnant females the plasma PAG concentration increased over basal concentrations 21-30 days after the estimated day of conception and peaked at the time of calving. The concentrations of E2 and E1SO4 remained low until 60 days before calving when a rapid increase was found for both hormones. The mean plasma concentration of PG-metabolite increased throughout pregnancy to a maximum at parturition. The estimated mean (range) gestation length was 216 (212-220) days. Judged from measures on reproductive organs collected from 86 free-ranging, semi-domestic female reindeer of unknown age presented for slaughter at Roros, Norway (63 degrees N, 11 degrees E) in the second week of December 1999, it was concluded that the breeding season lasted from early September until the end of November. The results also showed that plasma PAG concentration could provide a tool for detection of pregnancy in reindeer.


Assuntos
Estrona/análogos & derivados , Hormônios/sangue , Testes de Gravidez/veterinária , Prenhez/sangue , Rena/sangue , Animais , Animais de Zoológico , Estradiol/sangue , Estrona/sangue , Feminino , Finlândia , Idade Gestacional , Glicoproteínas/sangue , Gravidez , Proteínas da Gravidez/sangue , Progesterona/sangue , Prostaglandinas/sangue
8.
Physiol Biochem Zool ; 74(6): 907-16, 2001.
Artigo em Inglês | MEDLINE | ID: mdl-11731982

RESUMO

Variation in plasma urea and creatinine concentration and plasma urea:creatinine ratio (U:C) were studied in semidomestic free-ranging reindeer (Rangifer tarandus tarandus) on the Norwegian mainland, in wild Svalbard reindeer (Rangifer tarandus platyrhynchus), and in captive reindeer maintained either on a lichen-based diet or a protein-rich concentrate to investigate whether these parameters could be used as indicators of the nutritional status of reindeer. In the mainland animals, plasma creatinine concentration was high in winter and early spring and decreased by two-thirds toward the summer. The overall range in mean plasma creatinine concentration (+/-SE) was from 90+/-1.26 to 280+/-2.88 micromol/L. Mean plasma urea concentration (+/-SE) varied from 2.46+/-0.10 in winter up to 17.44+/-0.29 mmol/L in summer and autumn. Month of sampling explained 65% and 90% of the variation in plasma urea and creatinine concentrations, respectively, indicating that seasonality in the diet had the greatest influence on these parameters. Reindeer given lichens as the only feed showed an increase in plasma creatinine and a decrease in plasma urea concentration. Food restriction caused a temporary elevation in urea level but had no significant effect on plasma creatinine concentration. The slight effect of energy intake on urea and creatinine levels was supported by the fact that severe undernutrition in the Svalbard reindeer population had only a small effect on plasma urea and creatinine levels. Protein-rich pellet feed increased plasma urea from around 3 mmol/L to above 10 mmol/L and reduced creatinine concentrations to less than 100 micromol/L, suggesting that the protein content of forage is an important determinant of these blood parameters. Mean U:C ratio (+/-SE) in plasma varied from 8.9+/-0.28 to 120.8+/-1.88. Ratios above 20 appeared when protein intake was low and energy intake was restricted or when protein intake was high. Low ratios occurred when protein intake was low but energy intake adequate. Plasma urea and creatinine concentrations and the U:C ratio showed complex dynamics that were affected by both season and the protein and feed intake. We conclude that they appear to be difficult to interpret as single measures of nutritional status of reindeer.


Assuntos
Creatinina/sangue , Dieta , Proteínas Alimentares/metabolismo , Rena/fisiologia , Ureia/sangue , Animais , Animais Selvagens , Ingestão de Energia , Feminino , Líquens , Estado Nutricional , Estações do Ano
9.
Comp Biochem Physiol A Physiol ; 110(3): 243-52, 1995 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7712067

RESUMO

Concentrations of macrominerals; Na, K, Ca, Mg, P, and Cl were measured in different sections of the alimentary tract of five roe deer, Capreolus capreolus, kept in captivity and fed a diet of grass pellets and oats. By means of the non-absorbed marker-slaughter technique (using 51CrEDTA as marker), sites of secretion and absorption of minerals in the alimentary tract were determined. Large amounts of P, Na and K were secreted into the rumen, whereas Cl was secreted into the abomasum. The larger amounts of these minerals were absorbed from the distal small intestine and caecum/proximal colon. In the coiled colon, small quantities of Na, K and Cl were absorbed which is essential for the maintenance of mineral balance. Emphasis is put on the role of the large hindgut in concentrate selectors both with respect to fermentation and conservation of minerals and other nutrients.


Assuntos
Cervos/metabolismo , Sistema Digestório/metabolismo , Absorção Intestinal/fisiologia , Minerais/metabolismo , Animais , Avena , Cálcio/metabolismo , Cálcio/farmacocinética , Ceco/metabolismo , Cloro/metabolismo , Cloro/farmacocinética , Cromo/química , Colo/metabolismo , Dieta , Ácido Edético/metabolismo , Fezes/química , Intestino Delgado/metabolismo , Marcação por Isótopo , Magnésio/metabolismo , Magnésio/farmacocinética , Masculino , Minerais/farmacocinética , Fósforo/metabolismo , Fósforo/farmacocinética , Poaceae , Potássio/metabolismo , Potássio/farmacocinética , Sódio/metabolismo , Sódio/farmacocinética , Estômago de Ruminante/metabolismo , Distribuição Tecidual
10.
Comp Biochem Physiol Comp Physiol ; 107(3): 563-71, 1994 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-7909738

RESUMO

Alimentary and entire body pools of mineral (K, Na, P, Ca and Mg) and nitrogen were measured in 20 roe deer collected in February, April; May/June and September. Seasonal variations in nutrient concentration of the vegetation were recorded. The nitrogen, K, P, Ca and Mg concentration in the alimentary tract was in general synchronized with the seasonal nutrient concentration in the vegetation. The lower Na ruminal concentration and pool in early summer coincided with increased K intake. No seasonal variation in total body pools in relation to body mass were recorded, indicating no severe seasonal mineral constraints.


Assuntos
Fenômenos Fisiológicos da Nutrição Animal , Cervos/fisiologia , Estações do Ano , Ração Animal/análise , Animais , Proteínas Alimentares/análise , Minerais/análise , Minerais/metabolismo , Nitrogênio/análise , Nitrogênio/metabolismo , Noruega , Poaceae/química , Rúmen/metabolismo , Espectrofotometria , Espectrofotometria Atômica
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