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11.
The objective of this study was to evaluate the effect of dietary supplementation of whole flaxseed on sperm traits and sperm fatty acid profile in aged broiler breeder roosters. Twelve Ross 308 broiler breeder roosters (age: 52 weeks; weight: 4,900 ± 210 g) haphazardly allotted to three dietary treatments (each treatment contained four replicates and one bird in each replicate) for six weeks. Treatments were different levels of flaxseed (0% flaxseed [GFL0], 2% flaxseed [GFL2] and 4% flaxseed [GFL4]). The feed intake quadratically decreased (p < .05) with increasing whole flaxseed levels for the period (58 to 60 weeks). Sperm traits (semen volume and sperm concentration, sperm total and forward motility, sperm viability and morphology, sperm plasma membrane functionality) were evaluated every two weeks (four times), and sperm fatty acid profile was assessed at the end of the experiment. Semen volume, sperm concentration and sperm morphology were not affected by treatments. On week 60, GFL2 group showed a significantly lower percentage of total and progressive sperm motility and sperm membrane functionality in comparison with the control and GFL4 groups. Also, sperm viability was lower in GFL2 group compared with other groups on week 58 (p < .05). In terms of sperm fatty acid profile, GFL2 group significantly reduced the percentage of linoleic acid (C18:2 [n-6]) in comparison with other groups. However, any of the other fatty acids were not affected by dietary flaxseed. In conclusion, dietary supplementation of whole flaxseed could not improve the quality of aged broiler breeder roosters' sperm in this study, nor it could alter the sperm fatty acid profile; thus, it seems necessary to use some antioxidants such as vitamin E in the diet of aged broiler breeder roosters, when supplementing the diets with oils or oilseeds such as flaxseed.  相似文献   
12.
13.
Abdollah Bassiri 《Euphytica》1977,26(3):709-719
Summary Acid phosphatase and cathodal peroxidase isozyme patterns were used to identify nine introduced and five local cultivars of common safflower (Carthamus tinctorius L.) and seven ecotypes of wild safflower (C. oxyacantha Bieb.). Nineteen and nine bands, respectively, were readily observed for the phosphatase and peroxidase systems in the extracts from seedling shoots. Results indicated that both systems could be used jointly for complete identification of all the 21 seed sources used.Band frequencies and polymorphic indices (PI) were determined from acid phosphatase patterns using at least 92 individual seedlings of five introduced and five local cultivars and three wild ecotypes. Band frequencies ranged from complete absence in some to total presence in other populations. The mean PI for the introduced, local and wild safflowers were found to be 0.069, 0.052 and 0.058, respectively.The banding patterns of either enzyme system were similar in some instances for the cultivated and wild safflowers and there was as much variation between two cultivars as between a cultivar and a wild ecotype, indicating close genetic relationships between C. oxyacantha and C. tinctorius.  相似文献   
14.
Abortion in sheep and goats has become increasingly important worldwide because of the significant economic losses and potential zoonotic implication of commonly involved pathogens. Therefore, this cross-sectional study was conducted in southern Iran to detect the Chlamydophila abortus and Coxiella burnetii, as zoonotic pathogens, and Mycoplasma agalactiae, as a neglected abortifacient agent in small ruminants’ aborted fetuses, by using polymerase chain reaction (PCR). From a total of 300 aborted fetuses (183 sheep and 117 goats), 46 samples (15.5%) were positive by PCR, 11% for C. abortus, 2% for C. burnetii, and 3% for M. agalactiae. Also, the association of suggested risk factors with abortion due to these bacterial agents was investigated using univariable and multivariable logistic regression. Results of the statistical analysis showed significant association of C. abortus with flock size (OR?=?2.82, P?=?0.014), season (P?<?0.05), and the number of pregnancy in the aborted dam (OR?=?2.5, P?=?0.05). Our results indicated that C. abortus has a relatively substantial role in small ruminant abortions, and C. burnetii and M. agalactiae are likely important abortifacient agents in our region, too. Regarding veterinary and/or public health importance of these bacterial agents, more attention from veterinary and/or human health services and, maybe, a surveillance system for control and prevention of them are recommended.  相似文献   
15.
  1. Micronutrients, especially zinc, have an important role in normal metabolism and growth of broilers. Using novel technologies helps to synthesise novel zinc complexes to deliver this micronutrient more efficiently.

  2. In the present study, the effects of different zinc complexes and nano complexes on broiler performance were compared. Broilers in 6 groups were given basal diet (without zinc) and basal diet supplemented with zinc-sulphate, zinc-methionine, zinc-nano-sulphate, zinc-nano-methionine and zinc-nano-max (that was synthesised based on nanochelating technology) at a concentration of 80 mg/kg of diet.

  3. At 1–42 d of age, dietary zinc-nano-sulphate supplementation decreased weight gain and feed intake. However, feed conversion ratio was not influenced by treatments. Carcass yield (%) of birds in the zinc-nano-sulphate and control groups were dramatically reduced at 42 d of age and abdominal fat (%) increased in these groups.

  4. Relative to the control group, the antibody titre, spleen and bursa of Fabricius (%) were significantly higher in groups supplemented with zinc. Heterophil (%) was also significantly higher in the zinc-nano-methionine group in blood on d 42 compared to the control, zinc-sulphate and zinc-nano-sulphate.

  5. Compared to the controls, the mean malondialdehyde content in thigh tissue was significantly reduced in groups supplemented with zinc at the time 0, 50, 100 and 150 min after oxidation.

  6. Tibia zinc concentration in nanoparticle zinc samples was significantly higher relative to the control and zinc-sulphate groups.

  7. Taken together, our data indicate that delivery of zinc in the structure of zinc-nano-methionine and zinc-nano-max at concentrations of 80 mg/kg of diet improves growth performance. However, dietary zinc-nano-sulphate decreased growth performance in broilers.

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