scholarly journals Influence of diet on the morphology of the ruminal papillae in reindeer calves (Rangifer tarandus tarandus L.)

Rangifer ◽  
1996 ◽  
Vol 16 (3) ◽  
pp. 119 ◽  
Author(s):  
Terje D. Josefsen ◽  
Tove H. Aagnes ◽  
Svein D. Mathiesen
Keyword(s):  
Dry Matter ◽  
Rangifer Tarandus ◽  
Seasonal Pattern ◽  
Late Summer ◽  
Late Winter ◽  
Feeding Period ◽  
Cross Sectional ◽  
Sample Site ◽  
Different Seasons ◽  
Free Ranging

The influence of diet on the morphology of reindeer ruminal papillae was investigated in 4 groups of 3 free-ranging reindeer calves at different seasons, and in 11 groups of 3 reindeer calves fed experimental diets. Length, cross-sectional perimeter and density (number/cm2) of the ruminal papillae were measured in 4 sample sites in the rumen wall, and the ruminal surface enlargement factor (SEF) was calculated at each sample site. The range of group means were 2.3 to 3.4 mm for overall papillary length (mean of the four sample sites), 2.2 to 3.5 mm for overall cross-sectional perimeter, 85 to 189 papillae/cm2 for overall papillar density and 5.8 to 18.6 for overall SEF. Differences between sample sites wete observed, atrium ruminis having the highest and caudodorsal blind sac the lowest SEF (25% over and 24% below overall value, respectively). The differences between sample sites were considered to be small, indicating a homogenous ruminal content. The SEF of free-ranging animals showed a seasonal pattern, with high overall SEF (18.6) in September (late summer) and lower overall SEF {9.1) in April (late winter). Groups fed timothy silage with low content of cellulose (18.7% of dry matter) showed highest overall SEFs of the fed animals (17.8 and 13.9), while groups fed timothy silage with high content of cellulose (30.4%' of dry matter) showed lowest overall SEFs (5.8 and 7.0), indicating low ability to ferment silage with high content of cellulose. The SEF in animals fed experimental diets seemed partly to be influenced by SEF at the beginning of the feeding period.

scholarly journals Composition of late summer diet by semi-domesticated reindeer in different grazing conditions in northernmost Finland

Rangifer ◽  
2015 ◽  
Vol 35 (1) ◽  
pp. 39-52 ◽  
Author(s):  
Pauline Bezard ◽  
Sophie Brilland ◽  
Jouko Kumpula
Keyword(s):  
Diet Composition ◽  
Rangifer Tarandus ◽  
Coniferous Forest ◽  
Late Summer ◽  
Early Spring ◽  
Food Plants ◽  
Sample Site ◽  
Rotation System ◽  
Plant Groups ◽  
Microhistological Analysis

 This study aims to investigate the diet composition of semi-domesticated reindeer (Rangifer tarandus tarandus) in late summer in different kinds of grazing conditions in northernmost Finland. The composition of diet by reindeer was determined on the grounds of microhistological analysis of feces samples collected in early August in different seasonal grazing areas (winter or summer/year-round grazing areas) in three reindeer management districts. Although the proportion of different plant groups varied between the studied districts, the quantified group of ground lichens (which also contained small amounts of mushrooms) was the most abundant, varying from 33.0 to 46.4% in the analyzed samples. In general, there were significant differences in the proportions of lichen between districts, but not between grazing areas. The proportion of lichen in samples increased significantly when the amount of lichen pasture around a sample site increased. The proportion of dwarf shrubs and leaves in samples varied from 24.9 to 37.9% and differed significantly between districts, but not between grazing areas. In the same way, the proportion of graminoids varied between 20.9 and 36.2% and differed significantly between districts and also between grazing areas. Higher amounts of graminoids in feces were observed in summer/year-round grazing areas than in winter grazing areas. Finally, the proportion of bryophytes varied between 2.9 and 6.5% and was significantly different between districts, but not between grazing areas. An increase in old and mature coniferous forest around a sample site significantly increased the amounts of bryophytes in samples. The results indicate that reindeer adapt their summer diet composition according to the availability of food plants. The results also show that when reindeer are allowed to select their summer ranges freely, reindeer tend to use lichen pastures intensively also during summer, which causes a considerable reduction in lichens due to grazing and trampling. Therefore, a proper seasonal pasture rotation system to protect lichen pastures from grazing and trampling, from early spring to late autumn, is an essential part of sustainable pasture use in reindeer herding.

Seasonality and global public interest in psoriasis: an infodemiology study

2019 ◽  
Vol 96 (1133) ◽  
pp. 139-143 ◽  
Author(s):  
Qian Wu ◽  
Zhiwei Xu ◽  
Yi-Lin Dan ◽  
Chan-Na Zhao ◽  
Yan-Mei Mao ◽  
...  
Keyword(s):  
New Zealand ◽  
Public Interest ◽  
Seasonal Pattern ◽  
Late Summer ◽  
Early Spring ◽  
Late Winter ◽  
Search Volume ◽  
Early Autumn ◽  
Search Data ◽  
Google Search

ObjectiveAlthough patients with psoriasis frequently report seasonal changes in their symptoms, the seasonality of psoriasis has rarely been explored. This study aims to investigate the seasonal pattern of and global public interest in psoriasis using Google search data.MethodsInternet search data were collected from Google Trends. Data on the relative search volume (RSV) from January 2004 to December 2018 were retrieved using the term psoriasis. Cosinor analyses were conducted to examine the seasonality of psoriasis using data from two southern hemisphere countries (Australia and New Zealand) and four northern hemisphere countries (USA, Canada, UK and Ireland).ResultsOverall, searches for psoriasis steadily decreased between 2004 and 2010, and then rose from 2011 to 2018. On cosinor analyses, RSV of ‘psoriasis’ displayed a significant seasonal variation worldwide (p<0.025). Further analyses confirmed the seasonality of psoriasis-related RSV in Australia, New Zealand, USA, Canada, UK and Ireland (p<0.025 for all), with peaks in the late winter/early spring months and troughs in the late summer/early autumn months. The top 11 rising topics were calcipotriol/betamethasone dipropionate, ustekinumab, apremilast, shampoo, eczema, guttate psoriasis, seborrhoeic dermatitis, dermatitis, psoriatic arthritis, atopic dermatitis and arthritis.ConclusionThere was a significant seasonal pattern for psoriasis, with peaks in the late winter/early spring and troughs in the late summer/early autumn. Further studies are warranted to confirm the seasonal pattern of psoriasis using clinical data and to explore the underlying mechanisms.

Timing and synchrony of activity in caribou

1998 ◽  
Vol 76 (11) ◽  
pp. 1999-2009 ◽  
Author(s):  
Julie AK Maier ◽  
Robert G White
Keyword(s):  
Rangifer Tarandus ◽  
Activity Patterns ◽  
Food Limitation ◽  
Late Winter ◽  
Activity Data ◽  
Alaska Range ◽  
Time Activity ◽  
Focal Animal ◽  
Limited Food ◽  
Free Ranging

Activity data were analyzed to assess activity patterns of caribou (Rangifer tarandus granti). We hypothesized that equal day and night activity, termed nychthemeral activity, would be expected if food constitutes a limiting resource for a highly gregarious species. To test this hypothesis, we investigated activity patterns of two caribou populations at the same latitude: one captive with no food limitation and the other wild and free-ranging in the Alaska Range in interior Alaska known to be at the end of a 3-year low plane of nutrition. For captive caribou, activity patterns were determined from focal-animal behavioural observations each month except May. Data were collected on wild caribou using activity-recording radio collars in each of three seasons: late winter, postcalving, and midsummer. Wild and captive caribou exhibited nychthemeral activity and did not time activity to sunrise or sunset. Wild caribou exhibited no among-group synchrony. Within-group synchrony was high in both herds. Wild caribou exhibited significantly fewer cycles of activity than captive caribou. Longer resting bouts in late winter, and longer active bouts postcalving and in midsummer for wild caribou, were interpreted as behavioural responses to ecological effects of limited food availability, with and without snow, and disturbance by insects.

Food intake of reindeer in winter

2003 ◽  
Vol 141 (1) ◽  
pp. 93-101 ◽  
Author(s):  
P. V. STOREHEIER ◽  
B. E. H. VAN OORT ◽  
M. A. SUNDSET ◽  
S. D. MATHIESEN
Keyword(s):  
Food Intake ◽  
Dry Matter ◽  
Rangifer Tarandus ◽  
Dry Matter Intake ◽  
Faecal Output ◽  
Northern Regions ◽  
In Captivity ◽  
Ad Libitum ◽  
Few Data ◽  
Free Ranging

Management of semi-domesticated reindeer (Rangifer tarandus tarandus) in the northern regions have historically focused on reindeer–vegetation interactions, while few data on the food intake of these animals exist. Dry matter intake (DMI) was therefore estimated successively during winter in reindeer calves fed (i) ad libitum pelleted reindeer feed (RF-80; n=6), (ii) fed ad libitum mixed lichens (n=6) and (iii) in free-ranging reindeer calves (n=3) on natural winter pasture (March/April; 69 °N). Faecal output, determined with faeces collection bags, was 24±4, 6±3 and 22±3 g DM/day/kg BM0·75 in reindeer fed RF-80, mixed lichens and on winter pasture, respectively. Actual DMI of reindeer in captivity fed RF-80 and mixed lichens was 70±10 g DM/day/kg BM0·75 and 27±8 g DM/day/kg BM0·75, respectively. The DMI of the captive reindeer calves was accurately estimated on both diets on the basis of the digestibility of their diet and their faecal output. Using the same method, the DMI of free-ranging reindeer calves on natural winter pastures in northern Norway was estimated to be 34–61 g DM/day/kg BM0·75. The present study discusses factors that influence the food intake of reindeer in winter with emphasis on the seasonal regulation of appetite and DMI in these Arctic ruminants.

scholarly journals Estimating the daily dry matter intake of Svalbard reindeer in late winter

Rangifer ◽  
1987 ◽  
Vol 7 (1) ◽  
pp. 29 ◽  
Author(s):  
Nicholas Tyler
Keyword(s):  
Dry Matter ◽  
Rangifer Tarandus ◽  
Subcutaneous Fat ◽  
High Arctic ◽  
Energy Requirements ◽  
Late Winter ◽  
Substantial Part ◽  
Svalbard Reindeer ◽  
Fat Reserves ◽  
Alternative Suggestion

Svalbard reindeer (Rangifer tarandus platyrhynchus) store large reserves of subcutaneous fat during summer and autumn which, it has been suggested, might be sufficient to meet a substantial part of their energy requirements during winter. An alternative suggestion, however, is that fat is not their main source of energy after all and, moreover, that the principal role of their fat reserves is for enhancing reproductive success rather than for substituting for forage (Tyler, in press). Is it realistic to suggest that these high arctic herbivores could meet the greater part of their energy requirements in winter by feeding, given that the aerial biomass of available forage in Svalbard in late winter is very low? This question was investigated by using a simple model to predict what rate of food intake Svalbard reindeer would have to achieve to maintain energy balance in late winter. The results were surprisingly low: pregnant and nonpregnant females could mett their daily energy demands by consuming 3.1 and 1.7 g dry matter per grazing minute, respectively. This supports the suggestion that Svalbard reindeer could live principally off forage in winter.

The effect of nitrogen fertilizer on the seasonal production of irriagted perennial grasses in coastal New South Wales

1969 ◽  
Vol 9 (41) ◽  
pp. 610 ◽  
Author(s):  
EC Wolfe ◽  
FC Crofts
Keyword(s):  
Dry Matter ◽  
New South ◽  
New South Wales ◽  
Late Summer ◽  
Early Spring ◽  
Perennial Grasses ◽  
Late Winter ◽  
Late Autumn ◽  
Nitrogen Levels ◽  
South Wales

The seasonal productivity of eight perennial grasses at three nitrogen levels was measured in small pure-grass swards at Badgery's Creek, New South Wales. Highly significant differences in seasonal productivity were found between nitrogen levels in all four seasons, and between cultivars in summer, autumn, and winter. The response of the grasses to nitrogen was slightly greater at the high than at the medium level of nitrogen application in all seasons, and was highest in spring (about 40 lb of dry matter per lb of applied nitrogen) and lowest in mid-winter (about 8 lb/lb). Tall fescue was the most efficient responder to nitrogen in late summer and early autumn, Kangaroo Valley ryegrass in late autumn and late winter, and Currie cocksfoot in mid-winter. At a high level of nitrogen, the dry matter produced by Kangaroo Valley ryegrass and Currie cocksfoot in the late autumn to early spring period, the period of greatest feed shortage, was nearly as great as that produced over a similar period by sod-sown oats in earlier experiments at Badgery's Creek.

The rice rat Oryzomys palustris in a Delaware salt marsh: annual reproductive cycle

1993 ◽  
Vol 71 (7) ◽  
pp. 1457-1460 ◽  
Author(s):  
Kent E. Edmonds ◽  
Milton H. Stetson
Keyword(s):  
Salt Marsh ◽  
Breeding Season ◽  
Seasonal Pattern ◽  
Late Summer ◽  
Early Summer ◽  
Late Winter ◽  
Annual Reproductive Cycle ◽  
Monthly Basis ◽  
Lactating Females ◽  
Oryzomys Palustris

A population of the rice rat Oryzomys palustris inhabiting the Canary Creek salt marsh in Lewes, Delaware, was sampled on a monthly basis from September 1988 to December 1990. Males were assigned to the following age-classes on the basis of body mass: juveniles, 0 – 30 g; subadults, 31 – 50 g; adults, 51 g or greater. Testicular mass exhibited a seasonal pattern with lowest adult values in late autumn and early winter and peak values in late spring and early summer. Females showed similar patterns in uterine mass and vaginal patency. Pregnant and (or) lactating females were found from March to late September. The data suggest that the breeding season of the rice rat in southern Delaware begins in late winter and extends into late summer. Favorable environmental conditions may extend the breeding season for some individuals into autumn.

Comparative body composition strategies of breeding and nonbreeding female caribou

1999 ◽  
Vol 77 (12) ◽  
pp. 1901-1907 ◽  
Author(s):  
Ann C. Allaye Chan-McLeod ◽  
Robert G White ◽  
Don E Russell
Keyword(s):  
Body Composition ◽  
Body Fat ◽  
Rangifer Tarandus ◽  
Early Spring ◽  
Fat Deposition ◽  
Late Winter ◽  
Body Protein ◽  
Protein Deposition ◽  
Protein Mass ◽  
Free Ranging

We evaluated the effects of season and reproductive status on body fat and body protein masses of free-ranging female barren-ground caribou (Rangifer tarandus granti). Body fat mass fluctuated markedly during the year (by a factor of at least 2) in both reproductive classes, but whereas maximum fatness occurred in autumn (September-November) in nonbreeding females, it did not occur until late winter (March-April) in breeding females. Seasonal changes in dry body protein mass were relatively modest, with annual maxima averaging only 31-43% higher than annual minima. Moreover, seasonal differences between the reproductive classes were not significant except in November-December. Absolute fat deposition by both breeding and nonbreeding females was highest in summer, though fat deposition increased relative to protein deposition in autumn. Between June and September, the primary deposition of body protein in breeding females contrasted with the primary deposition of body fat in nonbreeding females. As a result, breeding females were highly compromised in their fat deposition but not in their protein deposition, which approximated levels in nonlactating females. Differences in body composition between breeding and nonbreeding females were highest in autumn and lowest in early spring because of divergence in summer and convergence in winter.

scholarly journals Early fall and late winter diets of migratory caribou in northwest Alaska

Rangifer ◽  
2018 ◽  
Vol 38 (1) ◽  
pp. 27-38 ◽  
Author(s):  
Kyle Joly ◽  
Matthew D. Cameron
Keyword(s):  
Rangifer Tarandus ◽  
Physiological Stress ◽  
Late Summer ◽  
Late Winter ◽  
Winter Habitat ◽  
Pregnant Females ◽  
Winter Diet ◽  
Early Fall ◽  
Forage Type ◽  
Winter Diets

Lichens are the primary winter forage for large herds of migratory caribou (Rangifer tarandus). Caribou select for lichens more than they are available across the landscape and they generally avoid, during winter, habitat that has been burned by wildfires for decades while lichen abundance recovers. However, the relative importance of lichens in the diet is subject to debate. From 2010-2013, we conducted one of the largest microhistological studies of the early fall (58 samples from 1 site) and late winter (338 samples from 58 sites) diets of barren-ground caribou. Lichens con­stituted ~ 71% of the late winter diets of caribou in northwest Alaska, whereas moss (11%) and shrubs (9%) were the next most common forage items. Early fall diets were very similar to late winter, perhaps because deciduous vegetation is senescent during both periods. Diets of males, non-pregnant females and pregnant females were not significantly different. Pregnancy was not associated with the abundance of any forage type during winter but was associated with higher physiological stress. This result was expected as fall body condition dictates conception, caribou are ‘capital’ breeders, and gestation can be energetically demanding. Caribou that migrated south (i.e., wintered south of 67.1°N) had lower levels of nutritional stress, higher levels of lichen in the diet, and lower levels of moss and shrubs compared to caribou that did not migrate south. Future investigations into the potential connection between lichen abundance in the winter diet and survivorship, as well as linking the late summer diets of individuals to their reproductive success, should be undertaken.

scholarly journals Dry matter accumulation and sheep grazing preference of six winter active annual legumes

2003 ◽  
Vol 11 ◽  
pp. 117-121
Author(s):  
M.G. Hyslop ◽  
M.W.A. Slay ◽  
C.A. Moffat
Keyword(s):  
Medicago Truncatula ◽  
Dry Matter ◽  
Seasonal Pattern ◽  
Block Design ◽  
Subterranean Clover ◽  
Late Winter ◽  
Dry Matter Accumulation ◽  
Sweet Clover ◽  
High Quality ◽  
Annual Legumes

Winter active legumes are suited to the mild winter areas of New Zealand, where they provide high quality forage in late winter and early to mid-spring. Six winter active annual legumes, persian clover, balansa clover, sweet clover, hybrid serradella, subterranean clover, and Medicago truncatula, were sown in a randomised complete block design with four replicates. Their dry matter (DM) accumulation and grazing preference to young sheep were measured every 3-6 weeks from sowing on 6 April 2000 until 24 October 2000. Total ungrazed DM production ranged from 5 500 kg/ha (sweet clover) to 9 300 kg/ha (balansa clover) over this period. The seasonal pattern of growth varied significantly between species, as did hogget grazing preference, with persian, balansa, and subterranean clover most preferred. These six plant species are capable of producing large amounts of high quality dry matter, but at all grazings, preference was extreme (measured by the number of sheep preferring to graze any one of the species when given a choice of all six), which may indicate the limited usefulness of some species. Key words: accumulative yield, grazing preference, Medicago truncatula, Melilotus albus, Ornithopus sativus x compressus, seasonal growth, sheep, Trifolium balansae, Trifolium respinatum, Trifolium subterraneum, winter active legumes

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