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71.
During cryopreservation, sperm was submitted to an increase in reactive oxygen species generation. This work aimed to improve the quality of frozen equine sperm after the addition of antioxidants lactoferrin (Lf) and catalase (Cat) to a freezing extender. Semen from six stallions was frozen with the extenders: F1) control, INRA 82 freezing extender, F2) F1 + 500 μg/ml Lf and F3) F1 + 200 IU/ml Cat. After thawing, sperm motility parameters, membrane functionality and integrity, and acrosome integrity and spontaneous acrosome‐reacted sperm were evaluated with a computer‐assisted sperm analysis, a hypoosmotic swelling test and epifluorescent microscopy, respectively. Nitrite, hydroperoxide and iron concentrations of frozen semen were measured with spectrophotometry. The percentage of functional membrane sperm treated with Lf was higher (50.7% ± 11.6%) compared to that of the control (37.6% ± 15.6%), while the iron (61.4 ± 11.6 vs 73.3 ± 13.8 mg/dl) and nitrite concentrations (16.3 ± 7.1 vs 25.9 ± 4.2 μM/μg protein) were lower, respectively (p < .05). Thus, it can be suggested that Lf protect stallion spermatozoon during freezing as it has increased the percentage of sperm with functional membrane and decreased the lipid oxidant agents.  相似文献   
72.
Melatonin and its receptors play a crucial role in the regulation of the animal reproductive process, primarily in follicular development. However, the role that melatonin performs in regulating hormones related with reproduction remains unclear. Melatonin and its receptors are present both in female and male animals’ organs, such as ovaries, heart, brain and liver. Melatonin regulates ovarian actions and is a key mediator of reproductive actions. Melatonin has numerous effects on animal reproduction, such as protection of gametes and embryos, response to clock genes, immune‐neuroendocrine, reconciliation of seasonal variations in immune function, and silence or blockage of genes. The growth ratio of reproductive illnesses in animals has raised a remarkable concern for the government, animal caretakers and farm managers. In order to resolve this challenging issue, it is very necessary to conduct state‐of‐the‐art research on melatonin and its receptors because melatonin has considerable physiognomies. This review article presents a current contemporary research conducted by numerous researchers from the entire world on the role of melatonin and its receptors in animal reproduction, from the year 1985 to the year 2017. Furthermore, this review shows scientific research challenges related to melatonin receptors and their explanations based on the findings of 172 numerous research articles, and also represents significant proficiencies of melatonin in order to show enthusiastic study direction for animal reproduction researchers.  相似文献   
73.
The effect of co‐culture of buffalo preantral follicles (PFs) with different somatic cells, i.e, cumulus, granulosa, ovarian mesenchymal and oviductal epithelial cells was studied. Large PFs (250–450 μm) were isolated by microdissecting the trypsin (1%) digested ovarian cortical slices. Cumulus cells were isolated by repeated pipetting of oocytes, granulosa cells were isolated by aspirating from punctured PFs and ovarian mesenchymal cells were isolated from ovarian cortex by scraping the cortical slices and passing through 20 μm filter. Preantral follicles were cultured in standard culture medium without somatic cells or co‐cultured with cumulus cells, granulosa cells, ovarian mesenchymal cells and oviductal epithelial cells for 80 days. The growth rate (μm/day) of the PFs was monitored by measuring follicular diameter on day 0, 30, 60 and 80 days of culture. The viability of PFs was evaluated by trypan blue staining. The results indicated that PFs co‐cultured with cumulus, granulosa and ovarian mesenchymal cells had a better development and survivality compared with control and those co‐culture with oviductal epithelial cells. Maximum growth and survivality of PFs were achieved when cultured with cumulus cells. It is concluded that inclusion of somatic cells in PF culture media had beneficial effect on the growth of PFs and cumulus cells supported maximum growth and survivality of PFs in vitro of all somatic cells tested.  相似文献   
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BACKGROUND: Dose–response relationships for antifeedant effects of H. lupulus extracts against larvae and adults of the Colorado potato beetle (CPB) were determined in laboratory conditions. The larval and adult beetles were fed on potato leaflets treated with H. lupulus extract ranging from 0.4 to 40 mg mL?1 in a no‐choice situation. Their feeding behavior was recorded, and larval growth and antifeedant indexes were calculated. RESULTS: H. lupulus treatments significantly affected larval growth rate, and at higher concentrations the larval weights were significantly reduced over the course of the assay. Adults of CPB were more sensitive to the extracts than the larvae, and, even at lower doses, adult beetles were arrested for longer periods than larvae. CONCLUSION: These results indicate that H. lupulus extracts may have potential for control of CPB, particularly in organic farms where conventional insecticides are not available. Copyright © 2012 Society of Chemical Industry  相似文献   
77.
Isothiocyanates have been shown to stimulate olfactory receptors on the antennae of the black bean aphid, Aphis fabae Scop. Single-cell recording techniques show that this aphid has receptors at the proximal primary rhinarium which are sensitive to n-butyl isothiocyanate. In laboratory assays, 4-pentenyl and n-butyl isothiocyanates were repellent at similar threshold concentrations. A. fabae was attracted to host-plant odour, but addition of either isothiocyanate to the airstream masked this attraction. Field trials on spring beans did not produce any consistent reduction in numbers of alate or apterous aphids on the crop, and yields were not improved by either compound.  相似文献   
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Abstract

Extract

In New Zealand, cobalt-containing drenches are recommended for the field diagnosis of cobalt deficiency, but find little use as a routine method of controlling the disease. For the latter purpose, cobaltized licks have a place on extensively-grazed untopdressed hill country. Otherwise, topdressing pastures annually with cobalt sulphate, usually as cobaltized superphosphate, has proved the best method of prevention (N.Z. Dept. Agric, 1954 N.Z. Dept. Agric. 1954. N.Z. Dept. Agric. Bull.,  [Google Scholar]; Andrews, 1956 Andrews, E. D. 1956. N.Z. J. Agric., 92: 239239.  [Google Scholar]). In Australia, however, greater reliance has been placed on drenches and licks, partly because cobalt topdressing is regarded as uneconomic on the extensive undeveloped holdings usually associated with cobalt deficiency in that country, and partly because the effects of cobalt applied to the land have often proved ephemeral, particularly on the acutely-deficient calcareous coastal sands (Lee, 1950 Lee, H. J. 1950. Aust. vet. J., 26: 152152. [Crossref], [PubMed] [Google Scholar]; Bennetts, 1955 Bennetts, H. W. 1955. J. Agric. West Ami., 4: 4242.  [Google Scholar]). However, recent work in South Australia opens up an entirely new approach to the control of cobalt deficiency disease. Dewey et al. (1958 Dewey, D. W., Lee, H. J. and Marston, H. R. 1958. Nature (Lond), 181: 13671367.  [Google Scholar]) report that when semi-porous pellets containing cobaltic oxide are administered to sheep they are retained in the reticulum, or less commonly in the rumen, and release a continuous and adequate supply of cobalt to the animal. Phalaris staggers and cobalt deficiency disease can be prevented in this way.  相似文献   
80.
Plant breeding has had a substantial effect on the productivity and health of ruminant animals in New Zealand by improving the quantity, quality and reliability of grazed temperate pastures. Genetic changes have affected annual pasture productivity, seasonal growth, digestibility, protein/energy balance, level of rumen undegradable protein, leaf properties affecting intake, resistance to foliar diseases, and reductions in compounds that have an adverse impact on the health, welfare and reproductive fertility of ruminant animals. Most plant improvement programmes have achieved genetic gains in excess of 1% per year for a variety of target traits, and these gains are likely to continue given the high genetic variation available within forage plants. Significant heritable variation exists to improve forage quality, particularly for soluble carbohydrate and fibre fractions in grasses, and in the rate at which these change during the season. Deleterious animal health and welfare effects can be alleviated through the use of non-toxic endophytes in grasses, that do not produce lolitrem B and ergovaline. Use of improved cultivars, with the appropriate management, can add value to animal products.  相似文献   
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