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1.
This study was conducted to identify and analyse the expression of gametogenesis‐associated genes and proteins in foetal and adult buffalo gonads of both the sexes. Relative quantification of the genes was determined by qPCR and Western blotting. Immunohistochemistry was also performed for various gametogenesis‐associated proteins in foetal and adult gonads of both the sexes. We observed significantly (p < 0.05) increased expression of primordial germ cell‐specific, meiotic as well as genes associated with oocyte maturation and development in foetal ovaries as compared to the adult ones. However, significantly (p < 0.05) increased expression of proteins associated with oocyte maturation like GDF9 and ZP4 was found in adult ovaries, indicating temporal regulation of mRNA translation during oogenesis. Meiotic genes showed significantly (p < 0.05) increased expression in adult testes as compared to foetal testes and ovaries, indicating onset of meiosis at a later stage in spermatogenesis. In general, the expression of primordial germ cell‐associated as well as meiotic genes was higher in adult testes, indicating the increased biological activity in the organ. Immunohistochemistry revealed localized expression of gametogenesis‐associated proteins in ovarian follicles and seminiferous tubules of testes, while the surrounding somatic tissues were devoid of these proteins. The study gives an understanding of the sequential and temporal events of gene expression as well as mRNA translation during male and female gametogenesis. It could also be concluded that follicles and seminiferous tubules are the functional units of the female and male gonads, respectively, and their function could be enhanced by appropriate chemical and genetic intervention of the somatic tissue immediately surrounding them. This assumes importance in the context that buffalo attains sexual maturity at an older age of 2–3 years and have smaller ovaries with lesser number of primordial follicles in comparison with cattle, which is suggested to be the main reason of their poor breeding performance.  相似文献   
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3.
Background:CE is a zoonotic parasitic infection caused by Echinococcus granulosus worldwide and is associated with economic losses among livestock animals. EG95 is an immunogenic antigen from the E. granulosus. Lactococcus lactis has been prested as a safe vehicle for antigen delivery. The goal of this study was to design a novel L. lactis strain displaying EG95 as a vaccine delivery system. Methods:The eg95 encoding gene fragment fused to the M6 anchoring protein was cloned into the pNZ7021 vector, and L. lactis NZ9000 displaying recombinant EG95 was constructed. The expression of an approximately 32-kDa EG95 protein was confirmed by Western blotting and immunofluorescence analysis. The immune responses were evaluated in BALB/c mice immunized orally and subcutaneously with the live and killed recombinant L. lactis, respectively. Results:Total IgG level in mice immunized with heat-killed recombinant L. lactis (pNZ7021-eg95) significantly increased compared to the control group. sIgA was significantly higher in mice received live recombinant L. lactis (pNZ7021-eg95) compared to the control mice. Splenic lymphocytes from immunized mice represented the high levels of IFN-γ and the low-levels of IL-4 and IL-10. Conclusion:Our results indicate that immunization with EG95-expressing L. lactis can induce both specific humoral and cellular immune responses in mice. Key Words: Echinococcus granulosus, Lactococcus lactis, Immunization, Vaccines  相似文献   
4.
Different amounts of nitrogen (N) and copper (Cu) in the forms of urea and copper sulfate (CuSO4·5H2O) were applied and their effects on diosgenin production and dry matter yield in fenugreek were investigated under farm cultivation conditions. High-performance liquid chromatography (HPLC) was employed to analyze diosgenin content. Diosgenin contents were measured in 25, 45 and 65 day-old leaves and in leaves at flowering stage and in fruits. The maximum diosgenin content was obtained in 45 day-old leaves. The results showed that simultaneous addition of Cu and N and the level of supply had significant effects on diosgenin production in leaves, fruits and dry matter yield. Simultaneous use of urea (100 kg ha?1) and copper sulfate (30 kg ha?1) increased diosgenin production and dry matter yield in 45 day-old leaves for 7.72 and 1.32 times, respectively, compared to unfertilized control group. But, the use of higher amounts of urea and copper showed a decrease in diosgenin production.  相似文献   
5.
Short-term recovery of soil physical properties on skid trails was investigated upon cessation of skidding operations and 1 year later. Bulk density and porosity were assessed at three levels of traffic intensity and two slope gradients. Compared to undisturbed areas, bulk density increased, total porosity and macroporosity decreased, and microporosity increased in the compacted areas immediately after skidding. In all cases, changes were significantly greater when traffic intensity was higher and when slopes were steeper. Surface soil compaction did not show any recovery over the 1-year period, illustrating the persistent effects of compaction on soil structure. In fact, surficial compaction further increased and macroporosity further decreased after 1 year of recovery, compared to immediately after skidding. While these changes may reflect inherent small-scale site variability or differences in soil moisture content at times of sampling, direct negative physical impacts on newly exposed soil (such as by raindrops), in addition to the loss of organic matter after canopy removal and skidding, likely delayed any physical recovery, particularly on heavily trafficked trails on steeper slopes. These results raise serious concerns about long-term resilience to traffic on forest soils and indicate the necessity to properly retire skid trails to avoid further soil degradation as trails age.  相似文献   
6.
Laboratory experiments were conducted to measure the functional and numerical responses of Eretmocerus mundus Mercet parasitizing cotton whitefly, Bemisia tabaci Gennadius. Parasitoids were isolated singly for 24 h in 5 cm petri dishes with either 5, 10, 20, 40, 60 or 100 second nymphal stages of B. tabaci. Results showed a typical type II functional response, with up to 43.2 hosts attacked when 100 hosts were provided. The rate of attack and handling time were 0.0465 and 0.3341 days, respectively. At above mentioned densities, the parasitoids lived an average of approximately 4 days. At host densities of < or =20 host/day, the total number of eggs laid was limited by the number of hosts available. Total fecundity was highest with an average of 196 eggs/female at density 100.  相似文献   
7.
Viruses are obligatory intracellular parasites that use cell proteins to take the control of the cell functions in order to accomplish their life cycle. Studying the viral-host interactions would increase our knowledge of the viral biology and mechanisms of pathogenesis. Studies on pathogenesis mechanisms of lyssaviruses, which are the causative agents of rabies, have revealed some important host protein partners for viral proteins, especially for most studied species, i.e. RABV. In this review article, the key physical lyssavirus-host protein interactions, their contributions to rabies infection, and their exploitation are discussed to improve the knowledge about rabies pathogenesis. Key Words: Host-Pathogen Interactions, Lyssavirus, Rabies  相似文献   
8.
Abstract

Sugar beet (Beta vulgaris L.) is cultivated mainly on saline soils. Low levels of salinity stimulate growth of this crop plant possibly due to production of broader leaves as sources of assimilates. In this work, six cultivars were studied under mild salinity (EC = 5.5 dS m?1) in a field experiment to analyse its effect on growth parameters and yield of storage root and sugar accumulation. An attempt was also made to determine the contributing role of photosynthetic gas exchange in response of sugar beet plants to salinity. Production of greater leaf area in salinized plants occurred only transitionally in the early growth period; in progression of the growing season it was decreased, and at 3rd harvest (100 days after treatment) it was significantly lower compared with control plants without cultivar differences. Leaf chlorophyll fluorescence, net photosynthesis rate, and stomatal conductance did not change by salinity significantly. Although, at the end of growth season, leaf area and potential photosynthesizing component of salinized plants on the basis of leaf area (LAR) or weight (LWR) were significantly lower than for control plants, weight of storage root and sugar content were up to 90 and 37% higher than in control plants, respectively. Consequently, a considerable higher yield under mild salinity conditions in sugar beet is not attributable to higher leaf area or, therefore, higher photosynthetic capacity of whole plants. Indeed, the storage roots benefit from lower dry matter and surface production of shoot during the late growing season (because of lower nitrogen assimilation and a slight drought stress of salinized plants) and a change in dry-matter partitioning in favor of roots takes place. However, a possible special effect of Na on carbon allocation for storage and structure and involvement of growth regulators in the change of root-shoot allometry could not be excluded.  相似文献   
9.
Lactating dairy cows (n = 667) at random stages of the oestrous cycle were assigned to either ovsynch (O, n = 228), heatsynch (H, n = 252) or control (C, n = 187) groups. Cows in O and H groups received 100 μg of GnRH agonist, i.m. (day 0) starting at 44 ± 3 days in milk (DIM), and 500 μg of cloprostenol, i.m. (day 7). In O group, cows received 100 μg of GnRH (day 9) and were artificially inseminated without oestrus detection 16–20 h later. In H group, cows received 1 mg oestradiol benzoate (EB) i.m., 24 h after the cloprostenol injection and were artificially inseminated without oestrus detection 48–52 h after the EB injection. Cows in C group were inseminated at natural oestrus. On the day of artificial insemination (AI), cows in all groups were assigned to subgroups as follows: human Chorionic Gonadotrophin (O‐hCG) (n = 112), O‐saline (n = 116), H‐hCG (n = 123), H‐saline (n = 129), C‐hCG (n = 94) and C‐saline (n = 93) subgroups. Cows in hCG and saline subgroups received 3000 IU hCG i.m. and or 10 ml saline at day 5 post‐AI (day 15), respectively. Pregnancy status was assessed by palpation per rectum at days 40 to 45 after AI. The logistic regression model using just main effects of season (summer and winter), parity (primiparous and pluriparous), method1 (O, H and C) and method2 (hCG and saline) showed that all factors, except method1, were significant. Significant effects of season (p < 0.01), hCG and parity (p < 0.01), and a trend of parity and season (p < 0.1) were detected. A clear negative effect of warm period on first service pregnancy rate was noted (p < 0.01). The pregnancy rate was the lowest in the H protocol during warm period (p < 0.05). Treatment with hCG 5 days after AI significantly improved pregnancy rates in those cows that were treated with the H protocol compared with saline treatments (41.5% vs 24.8%; p < 0.01). O and H were more effective in primiparous than in pluriparous cows (46.1% vs 29.9%; p < 0.1 and 43.6% vs 24.6%; p < 0.01). First service pregnancy rates were higher in primiparous hCG‐treated than in pluriparous hCG‐treated cows (57.9% vs 32.3%; p < 0.01). The pregnancy rate was higher for the hCG‐treated cows compared with saline‐treated cows during warm period (37.9% vs 23.6%; p < 0.001).  相似文献   
10.
ABSTRACT

In the present study, the effect of fish gelatin coating (FG; 4%, w/v) containing oregano (Origanum vulgare L.) essential oil (OEO; 1.2% w/v) on shelf-life extension of rainbow trout (Oncorhynchus mykiss) fillet stored under refrigerated storage (4 ± 1ºC) was investigated. The control and the treated fish samples were analyzed periodically for chemical (pH; total volatile basic nitrogen, TVB-N; peroxide value, PV; thiobarbituric acid, TBA) and microbiological (total viable count, TVC; psychrotrophic count) characteristics. The FG + OEO treatment produced significantly lower (p < 0.05) TVB-N values as compared to control and FG-coated samples after Day 6 and until the end of the storage period. The TBA values remained low and were found to fluctuate during storage. Results showed that TVC exceeded 6 log CFU g?1 on Day 8 of storage for control and FG-coated samples and Day 12 for samples coated with FG + OEO. The reduction of 1.05 and 0.83 log CFU g?1 of psychrotrophic counts was achieved by FG + OEO coating in trout fillet (p < 0.05) as compared with control and FG-coated samples, respectively. Therefore, the incorporation of OEO into FG coating may be a promising method of maintaining the storage quality of the rainbow trout fillet stored at refrigerated temperature.  相似文献   
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