151 research outputs found
Health and diseases of semi-domesticated reindeer in a climate change perspective
Climate change may affect reindeer herding and the health and disease of reindeer in several ways. One way of mitigating such changes is supplementary feeding, both in corrals and by bringing fodder to the animals on natural pastures. Feeding, when the right feed and feeding regime are used, may compensate for the loss of natural pastures and increase animal welfare. However, feeding may also cause issues with health and disease. These challenges may be associated with the feed and feeding regimes themselves, but also indirectly, by creating increased animal-to-animal contact and through the difficulty of maintaining hygienic conditions in corrals. In addition, climate change may have an impact on the presence of arthropod species and populations, such as ticks, mosquitoes and midges. These insects may cause increased levels of stress for the animals but can also be vectors for pathogens that may cause severe disease outbreaks, animal welfare issues and economic loss for reindeer herders. This chapter briefly presents the diseases and health problems that are directly or indirectly associated with reindeer feeding, as well as health challenges associated with arthropods and vector-borne diseases that are expected to be affected by climate change in the Arctic and sub-Arctic regions
A Multi Ant Colony Optimization algorithm for a Mixed Car Assembly Line
This paper presents an ant colony optimization algorithm to sequence the mixed assembly lines considering the inventory and the replenishment of components. This is a NP-problem that cannot be solved to optimality by exact methods when the size of the problem growth. Groups of specialized ants are implemented to solve the different parts of the problem. This is intended to differentiate each part of the problem. Different types of pheromone structures are created to identify good car sequences, and good routes for the replenishment of components vehicle. The contribution of this paper is the collaborative approach of the ACO for the mixed assembly line and the replenishment of components and the jointly solution of the problem
Case Report: Subclinical Verminous Pneumonia and High Ambient Temperatures Had Severe Impact on the Anesthesia of Semi-domesticated Eurasian Tundra Reindeer (Rangifer tarandus tarandus) With Medetomidine-Ketamine
Semidomesticated Eurasian tundra reindeer (Rangifer tarandus tarandus, n = 21) were scheduled twice for chemical immobilization with medetomidine-ketamine as part of a scientific experiment in June 2014. During the first round of immobilizations, seven animals developed severe respiratory depression (RD). Three individuals died, and 4 recovered. The ambient temperature during the 2 days of immobilization (June 3 and 4) was high (mean 13.9-17.6 degrees C) compared to the normal mean temperature for these 2 days (7-8 degrees C) based on statistical records. During the second round of immobilizations, using the same anesthetic protocol for the remaining animals as in the first round but conducted under cooler conditions (mean 6.6 degrees C for the period June 9-18), no signs of RD were observed. Clinical and pathological investigations indicated that the animals suffered from circulatory changes possibly caused by high ambient temperatures and granulomatous interstitial pneumonia due to Elaphostrongylus rangiferi larvae. These conditions, together with the cardiovascular effects of medetomidine, were likely causes of RD and the fatal outcome. We conclude that chemical immobilization of reindeer with medetomidine-ketamine should be avoided in May-June due to the potential risk when animals partly in winter coats encounter rising ambient temperatures and usually have parasites developing in their airways
Effect of dried leaves of Leucaena leucocephala on rumen fermentation, rumen microbial population, and enteric methane production in crossbred heifers
The effects of dietary inclusion of dried Leucaena leucocephala leaves (DLL) on nutrient digestibility, fermentation parameters, microbial rumen population, and production of enteric methane (CH4) in crossbred heifers were evaluated. Four heifers were used in a 4 × 4 Latin square design consisting of four periods and four levels of inclusion of DLL: 0%, 12%, 24%, and 36% of dry matter (DM) intake. Results showed that DM intake (DMI), organic matter intake, and gross energy intake (GEI) were similar (p > 0.05) among treatments. Apparent digestibility of organic matter, neutral detergent fiber, and energy decreased with increasing levels of DLL in the ration (p 0.05) rumen pH and total volatile fatty acids. Rumen microbial community was not affected (p > 0.05) by treatment. There was a linear reduction (p < 0.05) in CH4 emissions as the levels of DLL in the ration were increased. Results of this study suggest that an inclusion of 12% DM of ration as DLL enhances digestible CP and reduces daily production of enteric CH4 without adversely affecting DMI, rumen microbial population, and fermentation parameters
The Illumination and Growth of CRL 2688: An Analysis of New & Archival HST Observations
We present four-color images of CRL 2688 obtained in 2009 using the
Wide-Field Camera 3 on HST. The F606W image is compared with archival images in
very similar filters to monitor the proper motions of nebular structure. We
find that the bright N-S lobes have expanded uniformly by 2.5% and that the
ensemble of rings has translated radially by 0.07 in 6.65 y. The rings were
ejected every 100y for ~4 millennia until the lobes formed 250y ago. Starlight
scattered from the edges of the dark E-W dust lane is coincident with extant H2
images and leading tips of eight pairs of CO outflows. We interpret this as
evidence that fingers lie within geometrically opposite cones of opening angles
{\approx} 30{\circ} like those in CRL618. By combining our results of the rings
with 12CO absorption from the extended AGB wind we ascertain that the rings
were ejected at ~18 km s-1 with very little variation and that the distance to
CRL2688, v_{exp}{\dot\theta}_exp$, is 300 - 350 pc. Our 2009 imaging
program included filters that span 0.6 to 1.6{\mu}m. We constructed a
two-dimensional dust scattering model of stellar radiation through CRL2688 that
successfully reproduces the details of the nebular geometry, its integrated
spectral energy distribution, and nearly all of its color variations. The model
implies that the optical opacity of the lobes >~ 1, the dust particle density
in the rings decreases as radius^{-3} and that the mass and momentum of the AGB
winds and their rings have increased over time.Comment: (51 pages, 6 figures; accepted by ApJ
Infectious keratoconjunctivitis in semi-domesticated reindeer (Rangifer tarandus tarandus): a questionnaire-based study among reindeer herders in Norway and Sweden
Background - The effects of climate change, loss of pastureland to other land usage and presence of large carnivores are the main reasons for the increase in supplementary feeding of semi-domesticated reindeer (Rangifer tarandus tarandus) in Fennoscandia over the last decades. Feeding might expose reindeer to stress and increased animal-to-animal contact, leading to an increased risk of infectious disease transmission, such as infectious keratoconjunctivitis (IKC). As it can develop rapidly and be very painful, IKC is described as an important animal welfare concern and a potential source of economic loss. The aim of this study was to investigate the current presence of IKC and potential associations between IKC and supplementary feeding through an online questionnaire survey, distributed among reindeer herders in Norway and Sweden in 2021.
Results - Seventy-six reindeer herders (33 from Norway and 43 from Sweden) responded to the questionnaire, representing 6% and 4% of the registered reindeer herding groups in Norway and Sweden, respectively. Infectious keratoconjunctivitis was common, with 54 (71%) of the 76 herders that responded having observed clinical signs during the past 10 years. These signs were mainly observed as increased lacrimation, causing “wet cheeks”, but also as keratitis and conjunctivitis. Autumn and winter were the seasons in which IKC was observed most. The herders reported several measures, such as slaughter and isolation of affected reindeer, to counteract the spread of disease. The herding year 2019/2020 was associated with reports of outbreaks of IKC in herds as well as being the herding year where most herders (80%) had performed supplementary feeding. A significant association was found between IKC and feeding performed in an enclosure (odds ratio = 15.20), while feeding on free-range areas had a non-significant, negative, relationship with the appearance of IKC outbreaks (odds ratio = 0.29). Finally, there was a trend in the data suggesting that IKC affected calves especially.
Conclusions - Infectious keratoconjunctivitis is a common disease, mainly observed in winter and autumn. It usually has mild to moderately severe clinical signs. Our results imply that IKC is associated with stress and feeding situations and that calves might be more susceptible than adults, however, this needs to be confirmed with further studies, preferably at an individual animal level
Serological screening for tick-borne encephalitis virus in eight Norwegian herds of semi-domesticated reindeer
Tick-borne encephalitis virus (TBEV) is found in Ixodes ricinus ticks throughout the area where viable tick populations exist. In Norway, TBEV is found in I. ricinus from the south coast until Brønnøy municipality in Nordland County and the range of the vector is expanding due to changes in climate, vegetation, host animals and environmental conditions. TBEV might thus have the potential to establish in new areas when I. ricinus expand its geographical distribution. At present, there is little knowledge on the status of the virus in high-altitude areas of inland regions in Norway. It has previously been indicated that reindeer may be an important sentinel species and indicator of the spread of ticks and TBEV in high-altitude regions. In this study, 408 semi-domesticated Eurasian tundra reindeer (Rangifer tarandus tarandus) from eight herds, from Tana in Troms and Finnmark County in northern Norway to Filefjell in Innlandet and Viken Counties in southern Norway, were screened for TBEV antibodies using a commercial enzyme-linked immunosorbent assay (ELISA). We found 16 TBEV reactive reindeer samples by ELISA; however, these results could not be confirmed by the serum neutralization test (SNT). This could indicate that a flavivirusand not necessarily TBEV, may be circulating among Norwegian semi-domesticated reindeer. The results also indicate that TBEV was not enzootic in Norwegian semi-domesticated reindeer in 2013–2015. This knowledge is important as an information base for future TBEV and flavivirus surveillance in Norway
Liver sinusoidal endothelial cells show reduced scavenger function and downregulation of Fc gamma receptor IIB, yet maintain a preserved fenestration the Glmp gt/gt mouse model of slowly progressing liver fibrosis
Liver sinusoidal endothelial cells (LSECs) are fenestrated endothelial cells with a unique,
high endocytic clearance capacity for blood-borne waste macromolecules and colloids. This
LSEC scavenger function has been insufficiently characterized in liver disease. The
Glmpgt/gt mouse lacks expression of a subunit of the MFSD1/GLMP lysosomal membrane
protein transporter complex, is born normal, but soon develops chronic, mild hepatocyte
injury, leading to slowly progressing periportal liver fibrosis, and splenomegaly. This study
examined how LSEC scavenger function and morphology are affected in the Glmpgt/gt
model. FITC-labelled formaldehyde-treated serum albumin (FITC-FSA), a model ligand for
LSEC scavenger receptors was administered intravenously into Glmpgt/gt mice, aged 4
months (peak of liver inflammation), 9–10 month, and age-matched Glmpwt/wt mice. Organs
were harvested for light and electron microscopy, quantitative image analysis of ligand
uptake, collagen accumulation, LSEC ultrastructure, and endocytosis receptor expression
(also examined by qPCR and western blot). In both age groups, the Glmpgt/gt mice showed
multifocal liver injury and fibrosis. The uptake of FITC-FSA in LSECs was significantly
reduced in Glmpgt/gt compared to wild-type mice. Expression of LSEC receptors stabilin-1
(Stab1), and mannose receptor (Mcr1) was almost similar in liver of Glmpgt/gt mice and agematched controls. At the same time, immunostaining revealed differences in the stabilin-1
expression pattern in sinusoids and accumulation of stabilin-1-positive macrophages in
Glmpgt/gt liver. FcγRIIb (Fcgr2b), which mediates LSEC endocytosis of soluble immune
complexes was widely and significantly downregulated in Glmpgt/gt liver. Despite increased collagen in space of Disse, LSECs of Glmpgt/gt mice showed well-preserved fenestrae organized in sieve plates but the frequency of holes >400 nm in diameter was increased, especially in areas with hepatocyte damage. In both genotypes, FITC-FSA also distributed to
endothelial cells of spleen and bone marrow sinusoids, suggesting that these locations may
function as possible compensatory sites of clearance of blood-borne scavenger receptor
ligands in liver fibrosis
Chlamydia pecorum Associated With an Outbreak of Infectious Keratoconjunctivitis in Semi-domesticated Reindeer in Sweden
Infectious keratoconjunctivitis (IKC), the most common ocular disease in ruminants worldwide, has affected semi-domesticated Eurasian reindeer (Rangifer tarandus tarandus) for over 100 years, both as individual cases and in outbreaks affecting tens to hundreds of animals. Recurrent IKC outbreaks have been affecting a semi-domesticated reindeer herd in Östra Kikkejaure (Norrbotten county, Sweden) from 2014. The latest episode of these recurrent outbreaks, in winter 2016/2017, was investigated in this study. Clinical findings were in line with previous reports of IKC in semi-domesticated reindeer and the clinical signs displayed by the affected animals (n = 30) included increased lacrimation, follicular conjunctivitis, purulent secretions around the affected eyes and corneal edema. Laboratory analyses of the samples revealed the presence of Chlamydiaceae in most samples obtained from the clinically affected animals (98.3%, n = 60), but also a high seroprevalence of cervid herpesvirus 2 (CvHV2) antibodies (56.6%, n = 53). Moraxella bovoculi was isolated from nine IKC-affected animals during the outbreak (45.0%, n = 20). All affected animals were treated with long-acting antibiotics and recovered from the disease, testing negative for the presence of Chlamydiaceae DNA by PCR 16 days and 3 months after the initial treatment. For the first time, Chlamydia pecorum was identified in semi-domesticated reindeer, and the involvement of Chlamydiaceae in a clinical outbreak of IKC is reported. The CvHV2 seroprevalence (56.6%) and the data obtained from a previous outbreak in 2014 also suggest the involvement of the reindeer alphaherpesvirus in the recurrent outbreaks
Infectious Disease Outbreak Associated With Supplementary Feeding of Semi-domesticated Reindeer
Supplementary winter feeding of semi-domesticated reindeer (Rangifer tarandus tarandus) has become more common in Sweden and Norway due to reindeer pasture fragmentation and climatic conditions. With increased corralling and feeding, often associated with animal stress, increased animal-to-animal contact, and poor hygienic conditions, an altered range of health challenges and diseases may emerge. An outbreak of three different infectious diseases appeared simultaneously in a reindeer herd in Norrbotten County, Sweden. The animals were corralled and fed silage. Several animals in poor body condition stopped eating, with drool and discoloration of the hair coat around the mouth. There were large, black, necrotic lesions on the tongue and gingiva, with holes perforating the chin, indicative of oral necrobacillosis and Fusobacterium spp. infection. Simultaneously, animals were seen with proliferative lesions in the oral mucosa and on the lips, characteristic of contagious ecthyma and Orf virus infection. Furthermore, three animals had keratoconjunctivitis suggesting exposure to cervid herpesvirus 2 (CvHV2) and possibly secondary bacterial infections. DNA specific for Fusobacterium necrophorum and ORFV was detected in relevant tissue samples. Antibodies against CvHV2 were detected in 10 of 13 diseased and in four of 11 apparently healthy reindeer. Nine animals were found dead or were euthanized during the outbreak. Health risk factors associated with feeding and corralling may severely impact animal welfare and the herder's economy, and may represent an underestimated cost when replacing natural grazing with feeding
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