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71.
TM Hess JK Rexford DK Hansen M Harris N Schauermann T Ross TE Engle KG Allen CM Mulligan 《Journal of animal science》2012,90(9):3023-3031
The objective of this study was to examine the effects of different sources of dietary omega-3 (n-3) fatty acid supplementation on plasma, red blood cell, and skeletal muscle fatty acid compositions in horses. Twenty-one mares were blocked by age, BW, and BCS and assigned to 1 of 3 dietary treatments with 7 mares per treatment. Dietary treatments were: 1) control or no fatty acid supplement (CON), 2) 38 g of n-3 long chain, highly unsaturated fatty acid (LCHUFA) supplement/d provided by algae and fish oil (MARINE) containing alpha-linolenic acid (ALA), eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA), and docosapentaenoic acid (DPA), and 3) 38 g of n-3 LCHUFA supplement/d provided by a flaxseed meal (FLAX) containing ALA. Each supplement was added to a basal diet consisting of hay and barley and was fed for 90 d. Blood samples and muscle middle gluteal biopsies were taken at d 0, 30, 60 and 90 of supplementation. Plasma, red blood cell and skeletal muscle fatty acid profiles were determined via gas chromatography. Plasma linoleic acid (LA) and ALA were at least 10 and 60% less (P < 0.01), respectively, in the MARINE compared with the FLAX and CON groups. Plasma EPA and DHA were only detected in the MARINE group, and EPA increased 40% (P < 0.001) from d 30 to 60, and DHA 19% (P < 0.01) from d 30 to 90. Red blood cell LA and ALA were not different among treatments. Red blood cell EPA and DHA were only detected in the MARINE group, where EPA increased 38% (P < 0.01) from d 30 to 60, and DHA increased 56% (P < 0.001) between d 30 and 90. Skeletal muscle LA was at least 17% less (P < 0.001) in the MARINE group compared with the other treatments. Skeletal muscle ALA was 15% less (P = 0.03) in the MARINE group compared with FLAX and CON groups. Skeletal muscle EPA was at least 25% greater (P < 0.001) in MARINE group compared with other treatments and increased (P < 0.001) by 71% from d 30 to 60. Skeletal muscle DHA was at least 57% greater (P < 0.001) in the MARINE group compared with other groups and increased (P < 0.001) by 40% between d 30 and 90. As far as the authors are aware, this is the first study to demonstrate that dietary fatty acid supplementation will affect muscle fatty acid composition in horses. Incorporation of n-3 LCHUFA into blood and muscle depends directly on dietary supply of specific fatty acids. 相似文献
72.
SUMMARY: Free radical oxidation products, namely conjugated dienes, ultraviolet fluorescence (excitation 325 nm, emission 395 nm) and visible fluorescence (excitation 360 nm, emission 460 nm) were measured in equine synovial fluid exposed to free radicals In vitro and in the plasma and synovial fluids of horses with synovial effusions. The synovial effusions were induced by intra-articularly administered carrageenin (0.3 ml, 1%), which rarely resulted in clinical lameness. The free radicals were generated In vitro by mixtures of iron and ethylene diamine tetra acetate (Fe/EDTA) or mixtures of hypoxanthine and xanthine oxidase (HX/XO). The conjugated diene concentrations and intensity of ultraviolet fluorescence were negligible in plasma and synovial fluid specimens. No increase resulted from incubation of synovial fluids with either a free radical generating system or as a result of the induced inflammation. The intensity of visible fluorescence did not increase in specimens incubated with Fe/EDTA. However, the intensity of visible fluorescence increased in specimens incubated with HX/XO, in synovial effusions induced by carrageenin, in plasma and in synovial fluids aspirated from saline injected controls. The results indicate that the intensity of visible fluorescence of equine synovial fluid increases after exposure to free radicals and during synovitis in the horse, suggesting a possible role for free radicals in the pathogenesis of equine inflammatory joint diseas 相似文献
73.
74.
CEREAL YELLOW DWARF VIRUS IN GREAT BRITAIN 总被引:2,自引:2,他引:0
75.
In the summer of 1998, failures of methoprene field applications to control the mosquito Ochlerotatus nigromaculis (Ludlow) were noticed in several pastures in the outskirts of Fresno, California, USA. Effective control with methoprene had been achieved for over 20 years prior to this discovery. Susceptibility tests indicated that the Fresno Oc nigromaculis populations had developed several thousand‐fold higher LC50 and LC90 tolerance levels to methoprene compared with methoprene‐naïve populations. The synergists piperonyl butoxide (PBO), S,S,S‐tributyl phosphorotrithioate and 3‐octylthio‐1,1,1‐trifluoro‐2‐propanone had little synergistic effect, suggesting that the mechanism of methoprene tolerance was not mediated by P450 monooxygenase or carboxylesterase enzyme degradation. As part of initiating a resistance management strategy, partial reversion back to methoprene susceptibility was achieved in a resistant population after six consecutive applications of Bacillus thuringiensis israelensis Goldberg & Marga coupled with two oil and two pyrethrum + PBO applications. © 2002 Society of Chemical Industry 相似文献
76.
R M Mulligan 《American journal of veterinary research》1975,36(9):1391-1396
Of the 120 cases of mammary cancer occurring in 117 female dogs (15 spayed), 2 male dogs, and 1 dog of undetermined sex, 107 (nearly 90%) were observed in dogs 8 to 15 years old. Mammary tumors occurred in nearly 14% of 875 female dogs with neoplasms. Nearly 60% of 128 neoplasms were located in the 4th and 5th mammary glands. Of the 128 cancers in these 120 dogs, 85 were classified as duct carcinoma, 38 as lobular carcinoma, 3 as malignant mixed tumor, and 2 as duct and lobular carcinomas. Most duct carcinomas originated in the epithelial cells of ducts at all levels, and a few arose in previously benign duct papillomas. The lobular carcinomas arose in alveoli and developed into progressively larger lobules. A negative factor in the development of mammary cancer is ovariectomy before or shortly after the first estrous cycle in the dog and before the age of 40 in women. In both dog and man, aging is a positive factor in the development of mammary cancer. In women, other positive factors are nulliparity and inheritance; e.g., a high rate of breast cancer in close female relatives of Jewish extraction. An epidemiologic study of breast cancer in man and dog in high-risk countries(e.g., United States) and low-risk countries (e.g., Japan) is indicated. 相似文献
77.
R.J. Jørgensen P. Nansen SV.AA. Henriksen KR. Sejrsen J. Brolund Larsen S. Klausen 《Veterinary parasitology》1978,4(1):55-68
The performance of six groups of six calves each from a previous field experiment was followed from the beginning of housing until turning out seven months later. When housed the groups harboured different levels of infection with Ostertagia ostertagi and had corresponding weight and gain reductions. The most heavily infected groups improved rapidly following housing. Elevated serum pepsinogen levels decreased markedly, and approached normal values at eight weeks. Differences in serum pepsinogen levels between groups diminished considerably, but remained significant over the entire stabling period. The serum albumin level was low in the most seriously affected animals at the time of housing, but normal levels were restored within the first twelve weeks. In general, the number of parasite eggs in the faeces of the animals decreased, but there was considerable fluctuation. Apart from a single sampling date, no significant difference in egg per gram (EPG) could be demonstrated between the experimental groups during the stabling period.The calves were fed according to their age. The live weight differences between most and least affected groups diminished from 64 kg at the time of housing to 37 kg at the end of the stabling period. The reduction took place particularly during the first four weeks of housing.Considering both the grazing and stabling periods, it appeared that anthelmintic treatment twice during the period had no effect on the final live weight, whereas remeated treatments at three-week intervals resulted in an increase of 24 kg. Similarly, moving the animals to a clean pasture in mid-July resulted in an increase of 39 kg at the end of the stabling period when compared to calves which were not moved. Treatment of moved animals did not result in further body weight gain after seven months of housing.No significant correlation was found between parasite EPG of faeces and growth rate during the stabling period. However, a positive correlation was found between serum pepsinogen during the first eight weeks of housing and the weight gain over the entire stabling period. This was in contrast to the correlation experienced during the grazing period. 相似文献
78.
Alpha‐Linolenic Acid Supplementation in Tris Extender Can Improve Frozen–Thawed Bull Semen Quality
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A Kaka H Wahid Y Rosnina N Yimer AM Khumran AA Behan M Ebrahimi 《Reproduction in domestic animals》2015,50(1):29-33
The study was conducted to evaluate the effects of α ‐linolenic acid (ALA) on frozen–thawed quality and fatty acid composition of bull sperm. For that, twenty‐four ejaculates obtained from three bulls were diluted in a Tris extender containing 0 (control), 3, 5, 10 and 15 ng/ml of ALA. Extended semen was incubated at 37°C for 15 min, to allow absorption of ALA by sperm cell membrane. The sample was chilled for 2 h, packed into 0.25‐ml straws and frozen in liquid nitrogen for 24 h. Subsequently, straws were thawed and evaluated for total sperm motility (computer‐assisted semen analysis), membrane functional integrity (hypo‐osmotic swelling test), viability (eosin‐nigrosin), fatty acid composition (gas chromatography) and lipid peroxidation (thiobarbituric acid‐reactive substances (TBARS)). A higher (p < 0.05) percentage of total sperm motility was observed in ALA groups 5 ng/ml (47.74 ± 07) and 10 ng/ml (44.90 ± 0.7) in comparison with control (34.53 ± 3.0), 3 ng/ml (34.40 ± 2.6) and 15 ng/ml (34.60 ± 2.9). Still, the 5 ng/ml ALA group presented a higher (p < 0.05) percentage of viable sperms (74.13 ± 0.8) and sperms with intact membrane (74.46 ± 09) than all other experimental groups. ALA concentration and lipid peroxidation in post‐thawed sperm was higher in all treated groups when compared to the control group. As such, the addition of 5 ng/ml of ALA to Tris extender improved quality of frozen–thawed bull spermatozoa. 相似文献
79.
80.
The effects on the performance of dairy cows offered kale, swedes, and perennial ryegrass in situ and perennial ryegrass silage fed indoors to dairy cows pre‐partum during winter in Ireland was examined. Eighty‐eight spring‐calving dairy cows were randomly assigned to one of four offered treatments; (i) 8 kg of dry matter (DM) of kale leaf and stem + 4 kg DM of perennial ryegrass silage (treatment K), (ii) 8 kg DM of the root and leaf of swedes + 4 kg DM of perennial ryegrass silage (treatment S), (iii) 12 kg DM of perennial ryegrass herbage (treatment G) offered in situ and (iv) perennial ryegrass silage offered ad libitum indoors (treatment ID). Cows on treatments K, S and ID had a greater (P < 0·001) increase in body condition score (0·20, 0·14 and 0·50 units respectively) pre‐partum than cows on treatment G which lost 0·22 units. Pre‐partum treatment had no effect on variables of milk production in the following lactation. In the first 100 d of lactation, cows on treatment G pre‐partum had a lower milk fat concentration (35·6 g kg?1) compared with cows on treatments S and ID (38·3 and 39·3 g kg?1 respectively). There was no effect of treatment on the intervals between parturition and first insemination (mean 74·6 d) and conception (mean 96·1 d). The results suggest that offering kale and swedes to dairy cows pre‐partum resulted in a similar lactation performance to dairy cows grazing a perennial ryegrass sward or offered perennial ryegrass silage indoors. 相似文献