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1.
The study evaluated the reproductive performance of primiparous sows submitted to post‐cervical insemination (PCAI) compared with cervical artificial insemination (CAI). Difficulty with catheter introduction, the occurrence of bleeding or semen backflow during insemination, and volume and sperm cell backflow up to 60 min after insemination were also evaluated. Sows were homogenously distributed, according to body weight loss in lactation, lactation length, weaned piglets, weaning‐to‐oestrus interval and total born in previous farrowing, in two treatments: PCAI (n = 165) with 1.5 × 109 sperm cells in 45 ml (2.4 ± 0.04 doses per sow) and CAI (n = 165) with 3 × 109 sperm cells in 90 ml (2.5 ± 0.04 doses per sow). During PCAI, sows were inseminated in the absence of boars. Transabdominal real‐time ultrasonography was performed at oestrus onset, immediately before the first insemination and at 24 h after last insemination. There was no difference (P > 0.05) between treatments in farrowing rate (91.5% × 89.1%) and litter size (12.5 × 11.9 piglets born, respectively for PCAI and CAI sows). Successful passage of the intrauterine catheter in all the inseminations was possible in 86.8% (165/190) of sows initially allocated to PCAI treatment. Difficulty of introducing the catheter in at least one insemination did not affect the reproductive performance of PCAI sows (P > 0.05). Bleeding during insemination did not affect (P > 0.05) the farrowing rate in both treatments, but litter size was reduced in CAI and PCAI sows (P ≤ 0.06). Percentage of spermatozoa present in backflow within 1 h after insemination was greater in CAI than PCAI sows (P < 0.01). More than 85% of primiparous sows can be successfully post‐cervical inseminated with doses containing 1.5 × 109 sperm cells in the absence of the boar during insemination without impairing the reproductive performance.  相似文献   
2.
Objective – To compare the placement feasibility and amount of bone trauma induced by 3 intraosseous (IO) access techniques in cats: an automatic impact penetration device (A), an automatic rotary insertion device (B), and a manual IO needle (C). Design – Prospective ex vivo study. Setting – University. Animals – Eighteen adult mixed breed feline cadavers. Interventions – Cadavers provided 72 total IO insertion locations divided equally between the right and left humerus and tibia. The 3 IO techniques were randomly allocated to these locations. Time to successful insertion, ease of insertion, and success rate were recorded. Each insertion site was analyzed for the number of bone fragments and defect diameter by computed tomography. Measurements and Main Results – Device B had lower time of insertion (P=0.01) compared with devices A and C. Device B had better ease of insertion scores (P<0.01) compared with devices A and C. No differences were detected between insertion sites (tibia versus humerus). No differences in the number of bone fragments, defect diameter, or success rate were detected among devices (P=0.06, 0.31, and 0.14, respectively). Conclusions – All 3 IO access methods evaluated yield acceptable results. Device B is significantly faster and easier to place in cat cadavers when compared with other methods.  相似文献   
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4.
Legumes are important components of sustainable agricultural production, food, nutrition and income systems of developing countries. In spite of their importance, legume crop production is challenged by a number of biotic (diseases and pests) and abiotic stresses (heat, frost, drought and salinity), edaphic factors (associated with soil nutrient deficits) and policy issues (where less emphasis is put on legumes compared to priority starchy staples). Significant research and development work have been done in the past decade on important grain legumes through collaborative bilateral and multilateral projects as well as the CGIAR Research Program on Grain Legumes (CRP‐GL). Through these initiatives, genomic resources and genomic tools such as draft genome sequence, resequencing data, large‐scale genomewide markers, dense genetic maps, quantitative trait loci (QTLs) and diagnostic markers have been developed for further use in multiple genetic and breeding applications. Also, these mega‐initiatives facilitated release of a number of new varieties and also dissemination of on‐the‐shelf varieties to the farmers. More efforts are needed to enhance genetic gains by reducing the time required in cultivar development through integration of genomics‐assisted breeding approaches and rapid generation advancement.  相似文献   
5.
The midgut of insects is involved in digestion, osmoregulation and immunity. Although several defensive strategies are present in this organ, its organization and function may be disturbed by some insecticidal agents, including bioactive proteins like lectins and protease inhibitors (PIs) from plants. PIs interfere with digestion, leading to poor nutrient absorption and decreasing amino acid bioavailability. Intake of PIs can delay development, cause deformities and reduce fertility. Ingestion of PIs may lead to changes in the set of proteases secreted in the insect gut, but this response is often insufficient and results in aggravation of the malnutrition status. Lectins are proteins that are able to interact with glycoconjugates, including those linked to cell surfaces. Their effects on the midgut include disruption of the peritrophic matrix, brush border and secretory cell layer; induction of apoptosis and oxidative stress; interference with nutrient absorption and transport proteins; and damaging effects on symbionts. In addition, lectins can cross the intestinal barrier and reach the hemolymph. The establishment of resistant insect populations due to selective pressure resulting from massive use of a bioactive protein is an actual possibility, but this can be minimized by the multiple mode‐of‐action of these proteins, mainly the lectins. © 2018 Society of Chemical Industry  相似文献   
6.
Field experiments were conducted on four acid soils which were typical of the eastern section of the cropping region in southeastern Australia. The response of three cereal varieties to application of limestone or elemental S was measured as a function of soil pH. The cereals were selected to cover the known range of tolerance to acidity: Triticale (×Triticosecale wittmack cv. Currency) (tolerant); wheat (Tritcum aestivum cv. Matong) (moderately tolerant) and barley (Hordeum vulgare cv. Schooner) (sensitive). A two asymptote logistic equation was used to describe the relationship between soil pH and rates of limestone and elemental sulphur. The upper asymptotes for the four sites were well below the pH of lime saturation as the agriculturally practiced rates of lime were lower than the rates that could achieve the maximum pH in the field. The same equation was used to fit higher rates of lime application to a similar soil type to one of the four sites in this study and resulted in an upper asymptote of 7.26. Crop yield responses to lime application were well described by soil pHCa (0.01 M CaCl2). Soil pHCa ranges which gave 95% of maximum yield were pHCa 4.3–5.6 for Matong wheat, 4.4–4.8 for Currency triticale and 4.7–5.8 for Schooner barley. It was found that rainfall played an important role in limiting the yield response of crops to lime application. Lime reaction, lime requirement and grain yield models should include rainfall and soil water content as these influence the rate and extent of dissolution of limestone and subsequent plant response in a semi-arid environment.  相似文献   
7.
Contrary to the prediction of the Z-scheme model of photosynthesis, experiments demonstrated that mutants of Chlamydomonas containing photosystem II (PSII) but lacking photosystem I (PSI) can grow photoautotrophically with O2 evolution, using atmospheric CO2 as the sole carbon source. Autotrophic photosynthesis by PSI-deficient mutants was stable both under anaerobic conditions and in air (21 percent O2) at an actinic intensity of 200 microeinsteins per square meter per second. This PSII photosynthesis, which was sufficient to support cell development and mobility, may also occur in wild-type green algae and higher plants. The mutants can survive under 2000 microeinsteins per square meter per second with air, although they have less resistance to photoinhibition.  相似文献   
8.
Sheep were immunised with Corynebacterium pseudotuberculosis toxoid formulated as a monocomponent vaccine with aluminium adjuvant or in combination with 5 clostridial antigens, and also in the combined form with sodium selenate. Immunised and control sheep were experimentally infected 16 days after vaccination and slaughtered and inspected after a further 3 months to determine their resistance to infection. All 3 vaccines afforded an equal and high level of protection; 91% of vaccinated sheep exhibiting no lesions of caseous lymphadenitis compared with 51.5% affected sheep in the control group. Average lesion counts were 1.2 per affected vaccinated sheep and 4.5 per affected control sheep. Antitoxin responses to the clostridial toxoids incorporated in the combined vaccines were not affected by inclusion of the C pseudotuberculosis toxoid or the sodium selenate.  相似文献   
9.
Sheep were immunised with Corynebacterium pseudotuberculosis vaccines prepared from cell-free toxoid or from toxoid with formalin-killed cells of C pseudotuberculosis added. Resistance of sheep to infection was tested 6 months after immunisation by inoculation with caseous lymphadenitis pus. The outcome was assessed 3 months later by slaughter and inspection of the sheep for lesions of caseous lymphadenitis. immunised sheep were adequately protected against infection as shown by a significant reduction in the number of sheep exhibiting lesions compared with control sheep, and by fewer abscesses in affected vaccinated sheep than in affected control sheep. The protective potency of the vaccines was not improved by the inclusion of cells of C pseudotuberculosis.  相似文献   
10.
Replacement of native deep‐rooted grasses by shallow‐rooted ones has resulted in greater losses of water and nitrogen by drainage. To counter this effect we have tested the hypothesis that liming, and the conversion of annual grass pastures to perennial grass pastures, could improve the sustainability of grazing systems in the high rainfall zone (> 600 mm per annum) in southeastern Australia, through better use of water and nitrogen. A field experiment consisting of sixteen 0.135 ha (30 m × 45 m) grazed paddocks representing four pasture combinations (annual pasture (mainly Lolium rigidum) without lime (AP–); annual pasture with lime (AP+); perennial pasture (mainly Phalaris aquatica) without lime (PP–), and perennial pasture with lime (PP+)) was carried out from 1994 to 1997 on an acid Sodosol (Aquic Hapludalf) in southern New South Wales, Australia. Measurements were made of surface runoff, subsurface flow (on top of the B horizon) and soil water content. The results showed that perennial grass pastures, especially PP+, extracted approximately 40 mm more soil water each year than the annual grass pastures. As a result, surface runoff, subsurface flow and deep drainage were at least 40 mm less from the perennial pastures. These measurements were further supported by a simulation of soil water deficit and deep drainage for AP– and PP+ paddocks, using 10 years' past meteorological records. Overall, the results suggested that well‐grown, phalaris‐based pastures could reduce recharge to groundwater and make pastoral systems more sustainable in the high rainfall zone.  相似文献   
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