Behavioral Interference Between Sympatric Reindeer and Domesticated Sheep in Norway     

Jonathan E. Colman  Diress Tsegaye  Christian Pedersen  Ruben Eidesen  Herbjørg Arntsen  Øystein Holand  Alex Mann  Eigil Reimers  Stein R. Moe 《Strength and Conditioning Journal》2012,65(3):299-308

Interspecific interaction among sympatric ungulates is important in management and conservation. We investigated behavioral interference between sympatric wild or semidomestic reindeer (Rangifer tarandus tarandus) and sheep (Ovis aries) in two field studies and one enclosure experiment. For free-ranging wild and semidomestic reindeer, interference between the two species increased with decreasing distances, occurring only at less than 200 m and 30 m, for wild and semidomestic reindeer, respectively, and neither species consistently dominated the other. In a controlled, duplicated experiment we tested interference and confrontations at the feeding patch level among semidomestic reindeer and sheep within 40 × 50 m enclosures. When new reindeer or sheep were introduced into enclosures already occupied by reindeer, new reindeer resulted in significantly more interference and confrontations among individuals compared to new sheep; i.e., intraspecific interference was more prevalent than interspecific interference at equal densities. For all study areas, confrontations decreased with time after “first encounter,” indicating cohabituation. A sympatric use of pastures was not visually disruptive for recorded grazing behavior for either species.  相似文献   

Efficiency of Two Enucleation Methods Connected to Handmade Cloning to Produce Transgenic Porcine Embryos     

J Li  K Villemoes  Y Zhang  Y Du  PM Kragh  S Purup  Q Xue  AM Pedersen  AL Jørgensen  JE Jakobsen  L Bolund  H Yang  G Vajta 《Reproduction in domestic animals》2009,44(1):122-127

The purpose of our work was to establish an efficient-oriented enucleation method to produce transgenic embryos with handmade cloning (HMC). After 41–42 h oocytes maturation, the oocytes were further cultured with or without 0.4 μg/ml demecolcine for 45 min [chemically assisted handmade enucleation (CAHE) group vs polar body (PB) oriented handmade enucleation (OHE) group respectively]. After removal of the cumulus cells and partial digestion of the zona pellucida, oocytes with visible extrusion cones and/or polar bodies attached to the surface were subjected to oriented bisection. Putative cytoplasts without extrusion cones or PB were selected as recipients. Two cytoplasts were electrofused with one transgenic fibroblasts expressing green fluorescent protein (GFP), while non-transgenic fibroblasts were used as controls. Reconstructed embryos were cultured in Well of Wells (WOWs) with porcine zygote medium 3 (PZM-3) after activation. Cleavage and blastocyst rates were registered on day 2 and day 7 of in vitro culture respectively. Meanwhile, the total blastocyst cell number was counted on day 7. We found that the difference was only observed between blastocyst rates (38.6 ± 2% vs 48.1 ± 3%) of cloned embryos with GFP transgenic fibroblast cells after CAHE vs OHE. With adjusted time-lapse for zonae-free cloned embryos cultured in WOWs with PZM-3, it was obvious that in vitro developmental competence after CAHE was compromised when compared with the OHE method. OHE enucleation method seems to be a potential superior alternative method used for somatic cell nuclear transfer (SCNT) with transgenic fibroblast cells.  相似文献   

Response     

Hanne Kortegaard  & Thomas Eriksen  Vibeke Baelum 《The Journal of small animal practice》2009,50(2):104-105

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Socioeconomic impact of widespread adoption of precision farming and controlled traffic systems in Denmark   总被引：1，自引：0，他引：1  

Hans Grinsted Jensen  Lars-Bo Jacobsen  S?ren Marcus Pedersen  Elena Tavella 《Precision Agriculture》2012,13(6):661-677

In this study we assess the economic profitability of implementing various precision farming (PF) technologies and controlled traffic farming (CTF) on 4 main crops in Denmark. The study provides insight into technological requirements, and identifies related costs and benefits to farmers and the Danish society as a whole. At the farm level, the findings from the study indicate that an implementation of CTF systems may have a significant impact on fuel savings due to a reduced overlap with auto guidance systems and easier movement with tractors and tools in the field. The PF site-specific weed management approach may facilitate large savings in the use of herbicides. At the national level, the results clearly show that the benefits to the Danish economy of adopting this new technology is positive with increased income to farmers and a reduction in fuel consumption and pesticides/herbicides use. The obtained results reflect the long term economic effect of implementing new production methods in Denmark where soil fertility increases over time due to reduced traffic increasing yields. Over all, the Danish GDP is estimated to increase by 34?million?? due to the implementation of PF and CTF on larger farms in Denmark. The results also clearly show that adoption of PF and CTF farming systems will benefit the environment. The agricultural sectors input of environmental harmful inputs are reduced in all scenarios presented in this paper. The adoption of PF and CTF systems should thus be of interest to politicians since it clearly facilitates aims of environmental policies currently under implementation by the Danish government.  相似文献   

Dimension and design of the mating and control unit     

Bjarne K. Pedersen 《国外畜牧学(猪与禽)》2012,32(3)

1引言 配种和轻胎舍是母猪场中最重要的一个组成部分.因此,它必须能带来高妊娠率、高产仔、均衡的体况、较长的母猪使用寿命和低返情率.也就是说,配种和轻胎舍的设计必须有助于管理者获得较高的生产率.  相似文献   

Captopril caused a far lesser reduction in serum angiotensin-converting enzyme (ACE)     

Pedersen HD  Koch J 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》1999,13(1):76-77

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Dogs with heart diseases causing turbulent high-velocity blood flow have changes in platelet function and von Willebrand factor multimer distribution     

Tarnow I  Kristensen AT  Olsen LH  Falk T  Haubro L  Pedersen LG  Pedersen HD 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(4):515-522

The purpose of this prospective study was to investigate platelet function using in vitro tests based on both high and low shear rates and von Willebrand factor (vWf) multimeric composition in dogs with cardiac disease and turbulent high-velocity blood flow. Client-owned asymptomatic, untreated dogs were divided into 4 groups: 14 Cavalier King Charles Spaniels (Cavaliers) with mitral valve prolapse (MVP) and no or minimal mitral regurgitation (MR), 17 Cavaliers with MVP and moderate to severe MR, 14 control dogs, and 10 dogs with subaortic stenosis (SAS). Clinical examinations and echocardiography were performed in all dogs. PFA100 closure times (the ability of platelets to occlude a hole in a membrane at high shear rates), platelet activation markers (plasma thromboxane B2 concentration, platelet surface P-selectin expression), platelet aggregation (in whole blood and platelet-rich plasma with 3 different agonists), and vWf multimers were analyzed. Cavaliers with moderate to severe MR and dogs with SAS had longer closure times and a lower percentage of the largest vWf multimers than did controls. Maximal aggregation responses were unchanged in dogs with SAS but enhanced in Cavaliers with MVP (regardless of MR status) compared with control dogs. No significant difference in platelet activation markers was found among groups. The data suggest that a form of platelet dysfunction detected at high shear rates was present in dogs with MR and SAS, possibly associated with a qualitative vWf defect. Aggregation results suggest increased platelet reactivity in Cavaliers, but the platelets did not appear to circulate in a preactivated state in either disease.  相似文献   

Circulating concentrations of insulin-like growth factor-1 in dogs with naturally occurring mitral regurgitation     

Pedersen HD  Falk T  Häggström J  Tarnow I  Olsen LH  Kvart C  Nielsen MO 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(4):528-532

Insulin-like growth factor-1 (IGF-1), which mediates most effects of growth hormone, has effects on cardiac mass and function, and plays an important role in the regulation of vascular tone. In humans, an inverse relationship between degree of heart failure (HF) and circulating IGF-1 concentrations has been found in several studies. In dogs with HF, few studies have focused on IGF-1. We examined circulating IGF-1 concentrations in dogs with mitral regurgitation (MR) caused by myxomatous mitral valve disease. Study 1 included 88 Cavalier King Charles Spaniels (CKCSs) with a broad range of asymptomatic MR (median serum IGF-1: 76.7 microg/L; 25-75 percentile, 59.8-104.9 microg/L). As expected, standard body weight and percentage under- or overweight correlated directly with IGF-1. MR (assessed in 4 different ways) did not correlate with IGF-1. In study 2, 28 dogs with severe MR and stable, treated congestive HF had similar serum IGF-1 concentrations (median, 100.8 g/L; 25-75 percentile, 74.9-156.5 microg/L) as 11 control dogs (79.6 microg/L; 25-75 percentile, 64.1-187.4 microg/L; P = .84). In study 3, the plasma IGF-1 concentration of 15 untreated CKCSs with severe MR was 16.4 +/- 24.2 microg/L lower (P = .02) at the examination when decompensated HF had developed (80.8 +/- 30.9 microg/L) than at a visit 1-12 months earlier (97.2 +/- 39.8 microg/L), possibly in part due to an altered state of nutrition. The studies document that circulating IGF-1 concentrations are not altered before development of congestive HF in dogs with naturally occurring MR, but decrease by approximately 20% with the development of untreated HE In treated HF, circulating IGF-1 concentrations apparently return to within the reference range.  相似文献   

Feline lymphoma in the post-feline leukemia virus era     

Louwerens M  London CA  Pedersen NC  Lyons LA 《Journal of veterinary internal medicine / American College of Veterinary Internal Medicine》2005,19(3):329-335

Lymphoma (lymphosarcoma or malignant lymphoma) is the most common neoplasm of the hematopoietic system of cats and reportedly the cat has the highest incidence for lymphoma of any species. A 21-year retrospective survey of feline lymphoma covering the period 1983-2003 was conducted with the patient database at the Veterinary Medicine Teaching Hospital (VMTH) at the University of California, Davis, School of Veterinary Medicine. This period comprises the post-feline leukemia virus (FeLV) era. Feline lymphoma historically has been highly associated with retrovirus infection. Mass testing and elimination and quarantine programs beginning in the 1970s and vaccination programs in the 1980s dramatically reduced the subsequent FeLV infection rate among pet cats. The results of this survey confirm a significant decrease in the importance of FeLV-associated types of lymphoma in cats. In spite of this decrease in FeLV infection, the incidence of lymphoma in cats treated at the VMTH actually increased from 1982 to 2003. This increase was due largely to a rise in the incidence of intestinal lymphoma, and to a lesser degree, of atypical lymphoma. A high incidence of mediastinal lymphomas in young Siamese or Oriental breeds also was observed, supporting previous studies. Associations of intestinal lymphoma and inflammatory bowel disease and diet should be further considered.  相似文献   

Assessment of changes in hemostatic markers in Cavalier King Charles Spaniels with myxomatous mitral valve disease     

Tarnow I  Kristensen AT  Olsen LH  Pedersen HD 《American journal of veterinary research》2004,65(12):1644-1652

OBJECTIVE: To evaluate markers of hemostasis and their relationship to the degree of mitral regurgitation (MR) and platelet function in Cavalier King Charles Spaniels (CKCSs) with myxomatous mitral valve disease. ANIMALS: 76 clinically healthy CKCSs and 24 control dogs. PROCEDURE: All dogs underwent echocardiographic examination; various hemostatic, hematologic, and biochemical variables were evaluated in blood. The CKCSs were allocated to 1 of 3 groups on the basis of MR severity. In 8 control dogs and 8 CKCSs, plasma von Willebrand factor (vWF) multimer analysis was performed. RESULTS: Compared with control dogs, plasma fibrinogen concentration was higher in all CKCSs and related to left ventricular end diastolic diameter and left atrial-to-aortic root ratio among all CKCSs. The activated partial thromboplastin times and plasma D-dimer concentration were similar among the 4 groups. Plasma vWF concentration was lower in CKCSs with moderate to severe MR, compared with that of CKCSs with no MR and control dogs. There was a relationship between plasma vWF concentration and platelet function in CKCSs but not in control dogs. In 4 CKCSs with moderate to severe MR and low plasma vWF concentration, amounts of vWF high-molecular-weight multimers (HMWMs) were low. CONCLUSIONS AND CLINICAL RELEVANCE: In CKCSs, MR appeared to be associated with a low plasma vWF concentration and likely a loss of vWF HMWMs (possibly through their destruction via shear stress to the blood). The importance of the changes in plasma fibrinogen concentration and the thromboembolic risk in dogs with MR remain to be investigated.  相似文献