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131.
The current study examined the effects of inclusion of flaxseed in a red clover silage diet on growth, carcass quality, adipose tissue and muscle fatty acid (FA) profiles of beef steers. Twelve British×Continental crossbred steers (363±26.5 kg) were randomly assigned to two pens and fed diets containing 70% red clover silage, 15% steam rolled barley/vitamin–mineral supplement and either additional 15% steam rolled barley or 15% triple rolled flaxseed (all DM basis) for 215 d. Diet had no effect (P>0.05) on average daily gain or carcass quality atributes. Overall, FA profiles in all tissues followed similar trends when flaxseed was added to the diet but intramuscular fat had the highest proportions of n-3 and n-6 polyunsaturated FA (PUFA) while subcutaneous fat had largest proportions of conjugated linoleic acids (CLA) and perirenal fat had the highest proportions of trans-18:1 isomers, particularly vaccenic acid (VA). Feeding flaxseed increased (P<0.05) percentages of α-linolenic acid (ALA; 1.1–1.6% of total FA), total n-3 PUFA, conjugated linolenic acids, non-conjugated linoleic acids (mostly t11,c15-18:2), and led to unprecedented increases in CLA (mainly rumenic acid, RA; 1.1–2.9%), and trans-18:1 isomers (chiefly VA; 5.9–9.5%) in muscle and adipose tissues. Flaxseed also reduced individual and total n-6 PUFA, cis-monounsaturated FA, branched-chain FA and saturated FA (mainly 16:0) in beef lipids. Overall, feeding flaxseed in a red clover silage diet enhanced the levels of FA with a positive health image (ALA, 2-fold; RA, 3 to 4-fold and VA, 4 to 5-fold) and reduced the levels of less desirable FA (n-6 PUFA; 14:0, 16:0) in muscle and adipose tissues without adverse effects on growth and carcass quality. Differences in tissue FA composition were also noted, and high levels of VA in perirenal fat in particular have potential for use in testing for health effects and development of value added beef and other food products.  相似文献   
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ObjectiveTo evaluate the sedative effects of intravenous (IV) medetomidine (1 μg kg?1) and butorphanol (0.1 mg kg?1) alone and in combination in dogs.Study designProspective, blinded, randomized clinical trial.AnimalsSixty healthy (American Society of Anesthesiologists I) dogs, aged 6.2 ± 3.2 years and body mass 26 ± 12.5 kg.MethodsDogs were assigned to four groups: Group S (sodium chloride 0.9% IV), Group B (butorphanol IV), Group M (medetomidine IV) and Group MB (medetomidine and butorphanol IV). The same clinician assessed sedation before and 12 minutes after administration using a numerical scoring system in which 19 represented maximum sedation. Heart rate (HR), respiratory rate, pulse quality, capillary refill time and rectal temperature were recorded after each sedation score assessment. Sedation scores, sedation score difference (score after minus score before administration) and patient variables were compared using one-way anova for normally distributed variables and Kruskal–Wallis test for variables with skewed distributions and/or unequal variances. Where significance was found, further evaluation used Bonferroni multiple comparisons for pair-wise testing.ResultsBreed, sex, neuter status, age and body mass did not differ between groups. Sedation scores before substance administration were similar between groups (p = 0.2). Sedation scores after sedation were significantly higher in Group MB (mean 9.5 ± SD 5.5) than in group S (2.5 ± 1.8) (p < 0.001), group M (3.1 ± 2.5) (p < 0.001) and group B (3.7 ± 2.0) (p = 0.003). Sedation score difference was significantly higher in Group MB [7 (0–13)] than in Group S [0 (?1 to 4)] (p < 0.001) and Group M [0 (0–6)] (p < 0.001). HR decreased significantly in Groups M and MB compared with Group S (p < 0.05).Conclusion and clinical relevanceLow-dose medetomidine 1 μg kg?1 IV combined with butorphanol 0.1 mg kg?1 IV produced more sedation than medetomidine or butorphanol alone. HR was significantly decreased in both medetomidine groups.  相似文献   
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A prospective observational study was conducted in two Australian dairy herds to assess the potential for improving pregnancy rates (proportions of inseminations that result in pregnancy) to artificial insemination (AI) if the time of ovulation could be predicted with more certainty. Herd 1 calved year‐round and inseminations were performed during two periods each day. Herd 2 calved during autumn–winter and inseminations were performed only after the morning milking each day. In both herds, the AI to ovulation interval of enrolled cows was determined by trans‐rectal ovarian ultrasonography approximately 0, 12, 24 and 36 h after AI, and pregnancy was assessed by palpation per rectum 35–56 days after AI. Also, in Herd 1 vaginal electrical resistance (VER) measurements were taken at approximately 0, 12, 24 and 36 h after AI, and in Herd 2 cows were fitted with neck mounted activity meters that monitored cow activity count in 2‐h periods. There was substantial variation in the intervals from AI to ovulation within and between herds (mean ± SD 21.2 ± 10.7, n = 102; 14.7 ± 10.4, n = 100 in herds 1 and 2, respectively). Pregnancy rates were higher for inseminations close to, but preceding, ovulation. Using combined herd data (n = 202), the highest pregnancy rate (50.8%) was observed for inseminations between 0 and 16 h before ovulation, a period in which only a modest proportion of inseminations (31.2%) occurred. In contrast, pregnancy rate was significantly lower (28.7%; risk ratio 0.6; 95% CI 0.4–1.0; p = 0.039) for inseminations between 16 and 32 h before ovulation, a period where the highest proportion of inseminations (53.2%) occurred. Thus pregnancy rates could potentially be improved if a greater proportion of inseminations were conducted shortly before ovulation. In Herd 1, mean VER during the peri‐ovulatory period varied with time from ovulation. Lowest values (mean ± SEM, VER = 64.8 ± 1.2, n = 55) occurred approximately 18 h before ovulation and were significantly lower than measurements approximately 6 h before ovulation (67.4 ± 1.0; n = 73; p = 0.003). Further work is required to determine if VER can be used to identify ovulation time and hence the optimal time to inseminate in individual animals. In Herd 2 a modest proportion of inseminations (26.9%) occurred between 24 and 40 h after the onset of increased cow activity where the highest pregnancy rate (67.9%) was observed, whereas a significantly lower pregnancy rate (42.4%; risk ratio 0.6; 95% CI 0.4–0.9; p = 0.036) was observed for inseminations between 8 and 24 h after the onset of increased cow activity where the highest proportion of inseminations (56.7%) occurred. Thus cow activity monitoring may be useful to identify the optimal time to inseminate cows. Results from this study indicate that improved methods of ovulation prediction may allow better insemination timing relative to ovulation and consequently increased pregnancy rates.  相似文献   
135.
An increasing interest in sustainable forms of agriculture exists worldwide and the demand for varieties specifically adapted to organic and low-input agriculture is rising. As a consequence, breeding methods need to be refined accordingly. In order to get better insight into needs and possibilities with this regard, a comprehensive ring test was performed from 2006 to 2008 with 14 winter wheat varieties in 36 environments in major cropping regions of Austria, France, Romania and Switzerland. Environments were grouped into 9 different subsets according to input systems, years, and countries. Input system N0 consisted of 13 organic and 6 no-input trials; 17 trials in input system N received various levels of synthetic nitrogen. For grain yield (YLD) and protein yield (PYLD), significant G × E was detected. Countries had a stronger effect on both traits than systems. Overall, it was more efficient to select YLD and PYLD in N, for targeting both systems N and N0. For PYLD, direct testing within a given country was always more efficient than indirect selection. Many traits could be scored equally well in both systems, N and N0, but for some traits particularly important for organic agriculture, such as soil coverage, better differentiation was observed under organic conditions. Therefore, we agree with other authors that a commercially sustainable breeding program for organic and low-input agriculture should combine information from high and low-input levels and from diverse regions. Local testing of varieties, however, remains indispensable.  相似文献   
136.
Inherited epidermal dysplasia (IED), formerly called baldy calf syndrome, is a lethal disease of calves of Holstein-Friesian ancestry. The disease causes progressive illthrift and skin, horn and hoof lesions, which can be confused with inherited zinc deficiency. The clinicopathological features and ancestry of 10 affected calves in Gippsland, Victoria are described.  相似文献   
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It is widely accepted that sperm morphology is a strong indicator of semen quality. As the sperm head mainly comprises the sperm DNA, it is have been proposed that subtle changes in sperm morphology may be related to abnormal DNA content. Semen from four mongrel dogs was used to investigate DNA quality by means of the sperm chromatin structure assay (SCSA), and for computerized sperm morphometry (CASMA). Each sperm head was measured for nine primary parameters [head area (A), head perimeter (P), head length (L), head width (W), midpiece width (w), midpiece area (a), distance (d) between the major axes of the head and midpiece, angle (theta) of divergence of the midpiece from the head axis] and four parameters of head shape [FUN1, L/W; FUN2, 4piA/P(2); FUN3, (L - W)/(L + W); FUN4, piLW/4A]. Significant differences were found in all CASMA-derived parameters among dogs (p < 0.001). Linear regression models including sperm head shape factors 1, 3 and 4 predicted the extent of DNA denaturation (p < 0.001). We conclude that the CASMA analysis can be considered a powerful tool to improve the spermiogram.  相似文献   
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The study of multiple pathosystems has played a central role in the development of botanical epidemiology, leading to a number of approaches and concepts. Multiple pathosystems are facts, which are experienced by many non-cultivated, or cultivated, plant communities. The shapes and composition of multiple pathosystems vary in space and time because of their inherent structure of relationships, and also in response to management. Examples of variation in multiple pathosystems are given, of groundnut in Côte d’Ivoire, of wheat in Brittany, and of upland rice in northern Laos. Variation in the yield-reducing effects of multiple pathosystems is discussed, including interactions among disease elements, relationships with attainable performances, and linkages with production situations. Progress has been achieved in understanding the links between injury profiles, production situations, and attainable performances. Questions about the functioning and consequences of multiple pathosystems are central to defining the scientific bases for, the design of, and the implementing of IPM. The complexity of multiple pathosystems, however, remains a deterrent, not a challenge, to many plant pathologists. Progress achieved in designing production systems for hardy wheat in France, however, is very promising, because of the multidisciplinary science it involves, and because of the promise to deliver it carries. The concepts of epidemiological guilds and of guilds of harmful agents are offered as perspectives to address and manage syndromes of production and syndromes of disease.  相似文献   
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