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61.
62.
Etana Debela Adugna Tolera Lars Olav Eik Ragnar Salte 《Tropical animal health and production》2012,44(8):1939-1944
Two experiments were conducted to determine whether the proanthocyanidin (condensed tannin)-containing forage legumes Desmodium intortum cv Greenleaf and Sesbania sesban (accession 15019) could be integrated into a feeding management strategy as a means of Haemonchus contortus control in goats. The anthelmintic effects of condensed tannin extracts from the two legumes on H. contortus L3 larvae were studied in an in vitro larval migration inhibition system. The extracts inhibited larval migration in a dose-dependent manner, and at concentrations from 1,000???g/ml condensed tannin, the extract from D. intortum caused a significantly higher inhibition of larval migration than did the corresponding concentrations of the S. sesban extract (P?<?0.01). Prolonged feeding of tanniniferous forage legumes showed that animals receiving D. intortum had the lowest total worm burden, the lowest female to male parasite ratio, the lowest number of eggs in the uterus of each female worm and the lowest per capita fecundity (P?<?0.01). However, there was no change in the performance (weight gain) of parasite-infected goats probably due to incomplete removal of the parasite or prolonged confinement of goats in small pens, which calls for further investigation. However, since there is no single efficient method in control of parasites, based on the obtained data from this experiment, integrated feeding of D. intortum with other suitable method of parasite control is thus suggested. 相似文献
63.
A survey was conducted between April and July 2007 to generate information on dry season feeding management and livestock
poisoning in the southern rangelands of Ethiopia. A total of 119 pastoralists were interviewed using a semi-structured questionnaire.
Moreover, additional information was obtained through informal discussions. The study revealed that pastoralists have rich
knowledge of natural resource management and utilization and employ various strategies such as migration, collection of grasses
and pods, and cutting branches to overcome feed scarcity during dry/drought periods. Migration of livestock and people to
areas with better grazing is the widely used strategy. However, the implementation of this strategy is diminishing as a result
of changes such as bush encroachment, expansion of settlements, and crop cultivation in dry-season grazing lands. The respondents
also indicated the presence of poisonous plants in the rangeland, and about 20 such plants were identified by the respondents.
Various species and classes of livestock are reported to be affected by toxic plants particularly in the dry and early rainy
seasons when feed is in short supply. A more extensive survey is required to document all poisonous plants in the rangelands
and to identify the major toxic principles in the different species. Future development interventions should consider the
prevailing constraints and potentials of the rangelands with active participation of the pastoralists. 相似文献
64.
Sylvie L Benestad Lars Austb? Michael A Tranulis Arild Espenes Ingrid Olsaker 《Veterinary research》2012,43(1):87
Prion diseases such as scrapie in small ruminants, bovine spongiform encephalopathy (BSE) in cattle and Creutzfeldt-Jakob disease (CJD) in man, are fatal neurodegenerative disorders. These diseases result from the accumulation of misfolded conformers of the host-encoded prion protein (PrP) in the central nervous system. To date naturally-occurring PrP free animals have not been reported. Here we describe healthy non-transgenic animals, Norwegian Dairy Goats, lacking prion protein due to a nonsense mutation early in the gene. These animals are predicted to be resistant to prion disease and will be valuable for research and for production of prion-free products. 相似文献
65.
Krontveit RI Trangerud C Nødtvedt A Dohoo I Moe L Sævik BK 《Veterinary journal (London, England : 1997)》2012,193(1):206-211
The aim of the study was to measure the effect of radiological hip and elbow dysplasia status and breed on overall survival in a cohort of four large dog breeds in Norway. Privately owned dogs of the Newfoundland (NF), Labrador Retriever (LR), Leonberger (LEO), and Irish Wolfhound (IW) breeds were followed prospectively from birth to 10 years of age. The age of death/euthanasia was registered. A total of 501 dogs from 103 litters were enrolled. Kaplan-Meier survival curves were used to describe breed differences in survival times. The effects of radiological hip and elbow dysplasia status as well as breed were assessed using a Cox proportional hazards model. The variables 'sex' and 'living region' were explored as potential confounders. Among LRs, 60.2% of the dogs were still alive at 10 years of age, and the corresponding figures for NFs, LEOs, and IWs were 28.8%, 16.11%, and 6.4%, respectively. Radiological hip dysplasia status and breed were found to influence overall survival. Two different time-varying effects were observed in that with the IW the hazard of death increased linearly through time, while the effect of severe radiological hip dysplasia decreased logarithmically with time. Location influenced the death hazard and dogs living in suburban areas or cities had longer mean time to death and a lower hazard compared to dogs living in the countryside. Radiological elbow dysplasia status was not found to have an effect on overall survival. 相似文献
66.
Studying the impregnation and distribution of oil-based preservative in dried wood is complicated as wood is a nonhomogeneous, hygroscopic and porous material, and especially of anisotropic nature. However, this study is important since it has influence on the durability of wood. To enhance the durability of thermally modified wood, a new method for preservative impregnation is introduced, avoiding the need for external pressure or vacuum. This article presents a study on preservative distribution in thermally treated Scots pine (Pinus sylvestris L.) and Norway spruce (Picea abies (L.) Karst.) sapwood using computed tomography scanning, light microscopy, and scanning electron microscopy. Secondary treatment of thermally modified wood was performed on a laboratory scale by impregnation with two types of preservatives, viz. Elit Träskydd (Beckers) and pine tar (tar), to evaluate their distribution in the wood cells. Preservative solutions were impregnated in the wood using a simple and effective method. Samples were preheated to 170 °C in a drying oven and immediately submerged in preservative solutions for simultaneous impregnation and cooling. Tar penetration was found higher than Beckers, and their distribution decreased with increasing sample length. Owing to some anatomical properties, uptake of preservatives was low in spruce. Besides, dry-induced interstitial spaces, which are proven important flow paths for seasoned wood, were not observed in this species. 相似文献
67.
The objective of this experiment was to evaluate the effect of feeding different levels of enset corm as a supplement to sheep fed Rhodes grass hay. Thirty local yearling rams with a mean (±SD) body weight of 16.97 (±1.13) kg were used. Six sheep were allocated to each of the five treatments in a completely randomized design. The treatments were hay ad libitum and 129 g dry matter (DM) corm (T1), 188 g DM corm (T2), 248 g DM corm (T3), 100 g DM noug (T4) cake, and hay alone (T5). One hundred grams of noug seedcake was supplemented for all treatments except T5. Total DM and organic matter (OM) intakes of sheep in T1, T2, and T3 were the highest (P?<?0.05) compared with sheep in other treatments, while sheep in T5 consumed the lowest DM and OM. The total crude protein (CP) intakes of sheep in T3 and T2 were greater (P?<?0.05) than the other treatments, while sheep in T5 consumed the lowest CP. The apparent DM and OM digestibility coefficients of T1, T2, and T3 diets were higher (P?<?0.05) compared with T5. The lowest (P?<?0.05) CP digestibility was in T5, whereas the digestibility among the supplemented groups was similar (P?>?0.05). The daily body weight gain for T1, T2, and T3 diets was greater (P?<?0.05) than that of T5. The feed conversion efficiency for T1 and T2 was higher (P?<?0.05) than T5, while T4 had an intermediate value. The highest (P?<?0.05) nitrogen retention was in sheep fed T3 diet, while the lowest was in those fed T5. It is concluded that farmers can supplement enset corm at 129 g DM/day as an alternative energy source to improve the productivity of sheep for small-scale farmers under enset-livestock production systems. 相似文献
68.
69.
Lina J?nsson Lars Roepstorff Agneta Egenvall Anna N?sholm G?ran Dalin Jan Philipsson 《Acta veterinaria Scandinavica》2013,55(1):34
Background
Soundness of an individual horse is important for animal welfare and owner economy. However, knowledge of health status in normal horse populations is limited due to lack of systematic health recordings. The aim of the investigation was to study the prevalence of veterinary clinical findings in 4-5-year-old Swedish warmblood riding horses, and their influence on overall health scores, where associations to future longevity has been indicated.Results
The prevalence of clinical findings in 8,281 horses examined during 1983–2005 was studied according to a standardised protocol and related to overall health scores in linear statistical models. Effects of sex, age, examination event and changes over time were included. In total, 49% of the horses had clinical findings of medical health (MED), 42% in hooves (HOOF) and 74% of palpatory orthopaedic health (PALP). However, only 6%, 3% and 24% had moderate or severe findings, of MED, HOOF and PALP, respectively. Flexion test reactions were reported in 21% of the horses (5% moderate/severe), heavily influencing the overall score (H2). One fifth of these horses also had findings of unprovoked lameness while 83% had PALP findings (44% with moderate/severe findings). Acute clinical signs, i.e. heat or soreness, had a large influence on the H2 score but were rare, whereas more common clinical findings had smaller effects on overall health. Large variations in recorded health results were observed among events. A decrease in findings has occurred since 1983, in particular for PALP findings.Conclusions
Results of occurrence and relevance of evaluated clinical findings could be used for advice on preventive actions to keep horses sound, and possibly for benchmarking, and genetic evaluation of health traits. The distinct effect of event on recorded clinical findings emphasises that further harmonisation of veterinary examinations are desirable. 相似文献70.
Jan J. Olli Åshild Krogdahl Ted S. G. A. M. van den Ingh Lars E. Brattås 《Acta Agriculturae Scandinavica, Section A - Animal Sciences》2013,63(1):50-60
Abstract Four processed soybean products were evaluated as protein sources for Atlantic salmon: solvent-extracted soybean meal (SBM44), dehulled and solvent-extracted soybean meal (SBM50), dehulled full-fat soybean meal (FFSBM) and soybean concentrate (SBC). The soybean products replaced high-quality fish meal at levels corresponding to 0, 14, 28, 42 and 56% soybean protein of total protein. Dietary inclusion of SBC, at the expense of fish meal, did not affect weight gain, carcass lipids, fecal excretion of nutrients or fecal dry matter content significantly. The nutritive value of the SBC protein appeared comparable to that of the fish meal. The three other soybean products impaired performance increasingly with increasing levels of inclusion, indicating lower nutritive value than for the fish meal. The favourable results seen with SBC indicated a great potential of soybean to become an important protein source for Atlantic salmon through improved processing. 相似文献