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21.
The present study explores the effect of dietary sodium propionate on mucosal immune response and expression of antioxidant enzyme genes in zebra fish (Danio rerio). Six hundred healthy zebra fish (0.42 ± 0.06 g) supplied, randomly stocked in 12 aquariums and fed on basal diets supplemented with different levels of sodium propionate [0 (control), 5, 10 and 20 g kg?1] for 8 weeks. At the end of the feeding trial, mucosal immune parameters (TNF-α, IL-1β, Lyz), antioxidant enzyme (SOD, CAT) as well as heat shock protein 70 (HSP70) gene expression were measured. The results revealed feeding on sodium propionate significantly up-regulated inflammatory response genes (TNF-α, IL-1β, Lyz) in a dose-dependent manner (P < 0.05). However, antioxidant enzyme genes significantly down-regulated in the treated group compared with control (P < 0.05). Also, HSP70 gene expression was higher in the liver of fish fed the basal diet and deceased with elevation of sodium propionate levels in the diet. These results showed beneficial effects of dietary sodium propionate on mucosal immune response as well as the antioxidant defense of zebra fish.  相似文献   
22.
The present study was designed to investigate the effects of dietary apple cider vinegar (ACV) on digestive enzyme activity and growth performance as well as immune responses and antibacterial activity of skin mucus in green terror (Andinoacara rivulatus). Fish were fed diets supplemented with 0%, 1%, 2% and 4% of ACV (40.830 ppm acetic acid concentration) for 63 days. The final weight and weight gain values were observed to be significantly higher in fish fed with 2% of ACV compared to the control group (p < .05). ACV inclusion in the diets had significant effects on SGR (%) and FCR values (p > .05). ACV treatment resulted in a significant increase in the intestinal protease, α‐amylase, lipase and alkaline phosphatase activities compared to control (p < .05). The activities of digestive enzymes in fish fed with 2% and 4% of ACV diets were significantly higher than the other groups (p < .05). The total protein content, alternative haemolytic complement, alkaline phosphatase, total immunoglobulins and lysozyme activities of skin mucus increased significantly in fish fed with ACV diets (p < .05). In conclusion, administration of ACV enhanced digestive enzyme activity, growth performance, immune responses and the immune properties of skin mucus, and it can be used as a natural growth promoter and immunostimulant in green terror culture.  相似文献   
23.
Genetic parameters for carcass and meat quality traits of about 18-month-old Merino rams (n = 5870), the progeny of 543 sires from three research resource flocks, were estimated. The estimates of heritability for hot carcass weight (HCW) and the various fat and muscle dimension measurements were moderate and ranged from 0.20 to 0.37. The brightness of meat (colour L*, 0.18 +/- 0.03 standard error) and meat pH (0.22 +/- 0.03) also had moderate estimates of heritability, although meat relative redness (colour a*, 0.10 +/- 0.03) and relative yellowness (colour b*, 0.10 +/- 0.03) were lower. Heritability estimates for live weights were moderate and ranged from 0.29 to 0.41 with significant permanent maternal environmental effects (0.13 to 0.10). The heritability estimates for the hogget wool traits were moderate to high and ranged from 0.27 to 0.60. The ultrasound measurements of fat depth (FATUS) and eye muscle depth (EMDUS) on live animals were highly genetically correlated with the corresponding carcass measurements (0.69 +/- 0.09 FATC and 0.77 +/- 0.07 EMD). Carcass tissue depth (FATGR) had moderate to low genetic correlations with carcass muscle measurements [0.18 +/- 0.10 EMD and 0.05 +/- 0.10 eye muscle area (EMA)], while those with FATC were negative. The genetic correlation between EMD and eye muscle width (EMW) was 0.41 +/- 0.08, while EMA was highly correlated with EMD (0.89 +/- 0.0) and EMW (0.78 +/- 0.04). The genetic correlations for muscle colour with muscle measurements were moderately negative, while those with fat measurements were close to zero. Meat pH was positively correlated with muscle measurements (0.14 to 0.17) and negatively correlated with fat measurements (-0.06 to -0.18). EMDUS also showed a similar pattern of correlations to EMD with meat quality indicator traits, although FATUS had positive correlations with these traits which were generally smaller than their standard error. The genetic correlations among the meat colour traits were high and positive while those with meat pH were high and negative, which were all in the favourable direction. Generally, phenotypic correlations were similar or slightly lower than the corresponding genetic correlations. There were generally small to moderate negative genetic correlations between clean fleece weight (CFW) and carcass fat traits while those with muscle traits were close to zero. As the Merino is already a relatively lean breed, this implies that particular attention should be given to this relationship in Merino breeding programmes to prevent the reduction of fat reserves as a correlated response to selection for increased fleece weight. The ultrasound scan traits generally showed a similar pattern to the corresponding carcass fat and muscle traits. There was a small unfavourable genetic correlation between CFW and meat pH (0.19 +/- 0.07).  相似文献   
24.
Cadmium (Cd) is a major pollutant in soils as a result of extensive use of fertilizers, mining and industrial discharges. Zinc (Zn) and certain bacterial species have been known to alleviate Cd toxicity in plants. In this study, the individual and combined effects of the application of Zn and Pseudomonas species with the aim of reducing Cd stress in wheat cultivars were investigated. Plants (durum wheat and bread wheat) were exposed to different concentrations of Cd and Zn, and either P. putida or P. fluorescens in a growth chamber. Concentrations of Zn, Cd, chlorophyll (Chl), carotenoid, hydrogen peroxide (H2O2), and malondialdehyde (MDA), as well as antioxidant enzyme activities were assayed. The addition of Zn in soils reduced the toxicity of Cd in durum wheat more than in bread wheat even though there was more uptake of Zn in bread wheat. Analysis of variance showed that by using Zn fertilizer and Pseudomonas species the amounts of peroxidase (POD), polyphenoloxidase (PPO), MDA, and H2O2 were reduced at three growth stages. Surprisingly, with increasing Zn concentration, Cd concentration in plant tissue was slightly increased, which suggests that adding Zn to soil could facilitate Cd desorption from soil particles. Application of Pseudomonas and Zn could be a promising solution to reduce detrimental effects of Cd, especially in durum wheat.  相似文献   
25.

Milk has a high nutritional value and can affect human health. Therefore, it is important to know the factors affecting its quality. The purpose of this study was to evaluate the raw milk microbial quality and factors affecting it. A total of 4260 raw cow milk samples, which were collected from villages around Garmsar city, Iran, and their microbial load were registered at Garmsar Dairy Cow Association between 2013 and 2014, was used in the present study. The total average ± SD of microbial load concentration was 3.02?×?105?±?2.75?×?105 (CFU/ml). The average concentration of total bacteria in 2013 was 2.73?×?105?±?1.58?×?105 (CFU/ml) and in 2014 it was 3.32?×?105?±?3.93?×?105(CFU/ml). Seasonally, it was 2.94?×?105?±?1.72?×?105 (CFU/ml), 3.69?×?105?±?4.55?×?105 (CFU/ml), 2.91?×?105?±?1.62?×?105 (CFU/ml), and 2.63?×?105?±?1.67?×?105 (CFU/ml) for spring, summer, autumn, and winter, respectively. There was a significant difference in seasonal average microbial concentration of milk samples (p?<?0.05). The present study concludes that microbial load of milk can be affected by environmental and hygienic conditions. Ranchers need to pay more attention to hygiene especially in warm seasons. Because in case of high microbial load in raw milk, even after milk pasteurization, it is not possible to have a high-quality and desirable product. Milk producers and distributors need also awareness in order to reduce the incidence of secondary contamination. But, the main correction is to establish direct supervision of the Ministry of Health onto the health of dairy cow farmers by structural integrity of Veterinary Medical Organization as the global one health.

  相似文献   
26.
The present research was conducted to evaluate the effects of salinized water with boron and sodium chloride (NaCl) on seed germination of basil and cress. Treatments were: boron solution (25 and 50 mM), NaCl solution (25 and 50 mM) and distilled water as control. The highest germination percentage and mean daily germination of both plants were obtained in boron 25 mM. The highest mean germination time of basil and the day of 50% emergence of basil and cress were found in boron 50 mM. Radicle length of basil was reduced by increment of all salinity treatments; however, the highest cress radicle length was observed in 50 mM NaCl. It is concluded that these plants can tolerate salinized water during the germination stage to some extent, however, the cress show more tolerance to these salinities than basil.  相似文献   
27.
To assess the effects of levels of concentrate diet on growth and distribution of non-carcass components of feedlot-finished goats, 23 castrated Small East African-SEA (14.5 ± 0.5 month old and 20.1 ± 1.2 kg BWT) and 32 castrated F1 Norwegian crossbred (9.5 ± 0.5 month old, 17.1 ±1.2 kg BWT) goats were allotted to four levels of concentrate supplementation. The concentrate levels were: Zero access to concentrate (T0), 33% access to ad libitum concentrate allowance (T33), 66% access to ad libitum allowance (T66) and 100% access to ad libitum allowance (T100). Each animal had access to ad libitum grass hay. The weight of head, hocks and empty gastro intestinal tract as percentage of empty body weight (EBW) decreased (P < 0.05) with increasing levels of concentrate supplementation. The weight of liver as percentage of EBW increased (P < 0.05) with increasing levels of supplementation. Similarly, percentage of total non-carcass fat in both total body fat (TBF) and EBW increased (P < 0.05) with increasing levels of supplementation, mainly due to omental fat. Seemingly, percentages of total non-carcass fat in TBF for crossbred goats were numerically greater than that of SEA goats. Relative to EBW, liver had allometric growth coefficient greater than one, for both genotypes. Relative to both EBW and TBF, growth rate of omental fat was the fastest followed by kidney, mesenteric and pelvic fats. It is concluded that liver mass is responsive to dietary nutrient density and goats preferentially deposit fat internally as omental fat. Moreover, crossbred goats have higher proportion of non-carcass fat than SEA goats.  相似文献   
28.
This study aimed to evaluate the antilisterial and antioxidative effects of chitosan nanocomposites and rosemary extract coating on the fillet of Huso huso inoculated with Listeria monocytogenes during refrigerated storage (4°C). Fish fillets were subjected as control (without coating), 0.5% rosemary extract (RE), 1% chitosan (CS), and combination of chitosan and rosemary extract as chitosan nanocomposite (CS/RE). Then, samples were inoculated with L. monocytogenes. Subsequently, the chemical parameters (total volatile basic nitrogen (TVB-N), peroxide value (PV), pH, and thiobarbituric acid (TBA)) and antilisterial effects of coatings were monitored during 16 days of storage at 4°C. According to the results, CS/RE demonstrated a significant (p < 0.05) ability to inhibit the growth of L. monocytogenes from 4.14 log cfu/g to 2.23 log cfu/g at the end of the storage period, followed by CT and RET treatments, respectively, compared to the control. Even though samples coated with CS/RE had the lowest pH and TVB-N values (p < 0.05), this coating was not able to pause the protein denaturation after 8 days of storage (p > 0.05) compared to the other treatments. On the other hand, CS/RE coating retarded lipid oxidation by decreasing PV and TBA production in the samples compared to the control up to the end of refrigerated storage (p < 0.05).  相似文献   
29.
This study was designed to investigate the effects of feeding‐protected conjugated linoleic acid (CLA) on the semen production and sperm freezability in Holstein bulls. Twelve bulls were randomly assigned to two groups (n = 6 per group). Bulls received the normal diet (control group) or the normal diet top‐dressed with 50 g of CLA (treated group) for 10 weeks. The control group received 40 g/day calcium soap of fatty acid. Fresh and post‐thaw semen quality was assessed on ejaculates collected at the 0, 4, 6, 8 and 10 week of supplementation. Semen evaluations including sperm concentration, motion characteristics (subjective and computer‐assisted), viability (Eosin–Nigrosin), membrane integrity (hypo‐osmotic swelling test) and abnormality were conducted. Semen volume, sperm concentration and total sperm output were not affected by dietary treatment (p > .05). The proportion of spermatozoa with abnormal morphology in fresh semen significantly increased (p < .05) in the CLA‐fed group compared to control group. Also, in CLA‐fed group, the proportion of post‐thaw spermatozoa with abnormal morphology at week 10 of trial was significantly higher in CLA than control group (p < .05). Progressive motility tended to be increased in the CLA‐fed group, although dietary supplementation did not affect other CASA parameters or viability in fresh and frozen‐thawed sperm. In this study, CLA supplementation had little positive effect on fresh or post‐thaw sperm quality of Holstein bulls.  相似文献   
30.
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