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121.
Twenty‐four ejaculates from six (four ejaculates each) Surti buffalo bulls aged 4–8 years were used to assess various attributes of spermatozoa influencing the zona‐binding and zona‐penetration tests. Ejaculates from each bulls were subjected to in vitro sperm‐‐zona binding and sperm‐‐zona penetration tests (four replicates per bull) using immature buffalo oocytes. The average number of spermatozoa bound per oocyte was 27.79 ± 5.90. The average number of spermatozoa penetrated per oocyte was 3.35 ± 0.64. The average number of zona‐bound and ‐penetrated spermatozoa differed significantly between animals. Significant difference (p < 0.05) was observed between the plasmalemma integrity as assessed by eosin‐‐nigrosin stain and hypo‐osmotic swelling (HOS) test. Furthermore, the percentage of cells positive for the HOS test, i.e. functional membrane integrity (51.25 ± 2.32) was significantly (p < 0.05) higher than hypo‐osmotic swelling‐Giemsa (HOS‐G) test, i.e. the subpopulation of spermatozoa positive for functional membrane and acrosomal integrities (42.87 ± 4.56). The HOS test had significant correlations with plasmalemma integrity as measured by the vital stain, eosin‐‐nigrosin (r = 0.85, p < 0.05). The HOS‐G test also had significant correlation with plasmalemma integrity measured by vital stains such as eosin‐‐nigrosin (r = 0.90, p < 0.05) and fluorogenic stains [carboxyfluorescein diacetate (CFDA) and propidium iodide (PI); r = 0.92, p < 0.01] and HOS test (r = 0.93), acrosomal integrity (r = 0.86, p < 0.05) and mitochondrial membrane potential (r = 0.99, p < 0.01). The plasmalemma integrity (fluorogenic stain), functional membrane integrity (HOS test), subpopulation of spermatozoa positive for functional membrane and acrosomal integrities (HOS‐G test) and mitochondrial membrane potential had significant (p < 0.05) correlation with sperm zona binding and penetration. The present study indicates that these parameters could represent important determinants of sperm quality influencing zona binding and penetration. 相似文献
122.
Dieter Ebert Rudolf Wabersich Georg Kratzsch 《Archives of Agronomy and Soil Science》2013,59(4):291-303
Veränderungen in der Futterqualität von Phalaris arundinacea wurden in Abhängigkeit vom Schnittzeitpunkt im 1. Aufwuchs und variierter Nachwuchsdauer im 2. Aufwuchs untersucht. Daraus ließen sich die optimalen Nutzungszeitspannen von Phalaris arundinacea bestimmen. Überflutungen beeinflussen ebenfalls die Länge der optimalen Nutzungszeitspannen und die Futterqualität. Bei Phalaris arundinacea stieg der Rohfaser‐ und Ligningehalt sowie der K/N—Quotient mit zuneymendem physiologischen Alter an, wogegen der Rohprotein‐ und Kaliumgehalt sank. 相似文献
123.
M. Yasin Ashraf Attiya Gul Muhammad Ashraf F. Hussain G. Ebert 《Journal of plant nutrition》2013,36(11):1625-1637
Citrus, especially Kinnow, fruit yield and quality in Pakistan is not competitive with other countries, which could be mainly attributed to a lack of good nutrient management for citrus orchards. Many of the soils under these orchards have been reported as deficient in potassium (K). Therefore, work was initiated for improving citrus fruit yield, size, and quality through K nutrition management. Experiments were conducted in four districts of Punjab including Faisalabad, Toba Tek Singh, Jhang, and Sargodha and four rates of potash, i.e., 0, 50, 75 and 100 kg dipotassium oxide (K2O) ha?1 were applied using sulfate of potash (SOP) along with recommended rates of phosphorus (P) and nitrogen (N). Soils of all the selected sites were clay loam or sandy clay loam and deficient in K. The leaf analysis also showed that all the selected orchards were deficient in K. Application of K increased the fruit yield and quality but K at100 kg K2O ha?1 was more effective in increasing the fruit weight and size, and peel thickness than other K rates in all the selected orchards. Juice volume and percentage significantly increased when K was applied at 75 kg K2O ha?1 at all sites. Nutrient uptake like K, P, and N enhanced with the increase in K application rate, however, the highest calcium (Ca)+ magnesium (Mg) was recorded at 50 kg K2O ha?1. The results indicated that all rates of K application improved the fruit yield and quality and reduced fruit dropping, however, 75 kg K2O ha?1 rate was more effective as juice volume and percentage, total soluble solid (TSS)/acid ratio and nutrient uptake showed significant improvement. 相似文献
124.
Peter M. Kyne Rima W. Jabado Cassandra L. Rigby Dharmadi Mauvis A. Gore Caroline M. Pollock Katelyn B. Herman Jessica Cheok David A. Ebert Colin A. Simpfendorfer Nicholas K. Dulvy 《水产资源保护:海洋与淡水生态系统》2020,30(7):1337-1361
- The process of understanding the rapid global decline of sawfishes (Pristidae) has revealed great concern for their relatives, the wedgefishes (Rhinidae) and giant guitarfishes (Glaucostegidae), not least because all three families are targeted for their high‐value and internationally traded ‘white’ fins.
- The objective of this study was to assess the extinction risk of all 10 wedgefishes and six giant guitarfishes by applying the International Union for Conservation of Nature (IUCN) Red List Categories and Criteria, and to summarize the latest understanding of their biogeography and habitat, life history, exploitation, use and trade, and population status. Three of the 10 wedgefish species had not been assessed previously for the IUCN Red List.
- Wedgefishes and giant guitarfishes have overtaken sawfishes as the most imperilled marine fish families globally, with all but one of the 16 species facing an extremely high risk of extinction through a combination of traits: limited biological productivity; presence in shallow waters overlapping with some of the most intense and increasing coastal fisheries in the world; and overexploitation in target and by‐catch fisheries, driven by the need for animal protein and food security in coastal communities and the trade in meat and high‐value fins.
- Two species with very restricted ranges, the clown wedgefish (Rhynchobatus cooki) of the Malay Archipelago and the false shark ray (Rhynchorhina mauritaniensis) of Mauritania, may be very close to extinction.
- Only the eyebrow wedgefish (Rhynchobatus palpebratus) is not assessed as Critically Endangered, with it occurring primarily in Australia where fishing pressure is low and some management measures are in place. Australia represents a ‘lifeboat’ for the three wedgefish and one giant guitarfish species occurring there.
- To conserve populations and permit recovery, a suite of measures will be required that will need to include species protection, spatial management, by‐catch mitigation, and harvest and international trade management, all of which will be dependent on effective enforcement.
125.
JM Anchordoquy JP Anchordoquy MA Sirini SJ Picco P Peral‐García CC Furnus 《Reproduction in domestic animals》2014,49(5):865-874
The aim of this study was to investigate the influence of zinc (Zn) on the health of cumulus–oocyte complex (COC) during in vitro maturation (IVM). Experiments were designed to evaluate the effect of Zn added to IVM medium on: DNA integrity, apoptosis, cumulus expansion and superoxide dismutase (SOD) activity of cumulus cells (CC). Also, role of CC on Zn transport during IVM was evaluated on oocyte developmental capacity. DNA damage and early apoptosis were higher in CC matured with 0 μg/ml Zn compared with 0.7, 1.1 and 1.5 μg/ml Zn (p < 0.05). Cumulus expansion did not show differences in COC matured with or without Zn supplementation (p > 0.05). Superoxide dismutase activity was higher in COC matured with 1.5 μg/ml Zn than with 0 μg/ml Zn (p < 0.05). Cleavage and blastocyst rates were recorded after IVM in three maturation systems: intact COCs, denuded oocytes with cumulus cells monolayer (DO + CC) and denuded oocytes (DO). Cleavage rates were similar when COC, DO + CC or DO were matured with 1.5 μg/ml Zn compared with control group (p > 0.05). Blastocyst rates were significantly higher in COC than in DO + CC and DO with the addition of 1.5 μg/ml Zn during IVM (p < 0.01). Blastocyst quality was enhanced in COC and DO + CC compared with DO when Zn was added to IVM medium (p < 0.001). The results of this study indicate that Zn supplementation to IVM medium (i) decreased DNA damage and apoptosis in CC; (ii) increased SOD activity in CC; (iii) did not modify cumulus expansion and cleavage rates after in vitro fertilization; (iv) improved subsequent embryo development up to blastocyst stage; and (v) enhanced blastocyst quality when CC were present either in intact COC or in coculture during IVM. 相似文献
126.
Abstract AIM: To compare the peri-operative electroencephalogram (EEG) responses and post-operative analgesic efficacy of pre-operative morphine or tramadol with a combination of low-dose pre-operative morphine and post-operative tramadol, in dogs undergoing ovariohysterectomy. METHODS: Dogs undergoing routine ovariohysterectomy were treated with either pre-operative morphine (0.5 mg/kg S/C, n=8), or tramadol (3 mg/kg S/C, n=8), or pre-operative low-dose morphine (0.1 mg/kg S/C) and post-operative tramadol (3 mg/kg I/V, n=8). All dogs received routine pre-anaesthetic medication, and anaesthesia was induced with I/V thiopentone to effect and maintained with halothane in oxygen. Respiratory rate, heart rate, end-tidal halothane tension (EtHal) and end-tidal CO2 tension (EtCO2) were monitored throughout surgery. The EEG was recorded continuously in a three electrode montage. Median frequency (F50), total power (Ptot) and 95% spectral edge frequency (F95) of the EEG power spectra were compared during different 100-second periods of surgery: prior to and during skin incision, ligation of each ovarian pedicle, ligation of uterine body and skin closure. Post-operatively, pain was assessed using the short form of the Glasgow composite measure pain scale (CMPS-SF). RESULTS: There was no difference in F50 or Ptot of the EEG between baseline and noxious surgical events within each treatment group, or between the three groups (p>0.05). The mean F95 was higher during the first three periods of surgery for dogs administered tramadol and low-dose morphine than those that received 0.5 mg/kg morphine (p=0.001). Dogs that received low-dose morphine and tramadol had lower CMPS-SF pain scores after ovariohysterectomy than those that received either tramadol or morphine alone (p=0.001). There was no difference in pain scores between dogs in the latter two groups. CONCLUSION AND CLINICAL RELEVANCE: Tramadol and morphine administered pre-operatively provided an equal degree of post-operative analgesia in dogs after ovariohysterectomy. A combination of pre-operative low-dose morphine and post-operative tramadol produced better post-operative analgesia than either drug administered alone pre-operatively. Administration of analgesics pre- and post-operatively could result in improved post-operative well-being of ovariohysterectomised dogs. 相似文献
127.
The disposal of sewage wastes may cause severe environmental problems as was graphically demonstrated with pollution on Sydney's ocean beaches in recent years. Sewage sludges contain valuable plant nutrients and organic matter which can improve the fertility and structure of the soil. However, human parasites, pathogenic micro-organisms and chemicals capable of causing soil contamination, phytotoxicity and residues in animal products may also be present. Although sewage sludge is frequently spread on agricultural land overseas, it is not common in Australia and most states do not have specific regulations to minimise risk and promote good practice. A sludge-to-land program began in the Sydney region in 1990. It follows guidelines written by NSW Agriculture to encourage beneficial agricultural use of sludge by adoption of environmentally sustainable practices. This article describes the major risks to the food-chain and the environment, which may be associated with applying sewage sludge to agricultural land. It summarises how the risks are managed, and where further research data are required. 相似文献
128.
Thinning-experiments were carried out with carbaryl, ethephon (CEPA) and the amide of naphthaleneacetic acid (NAAm) in the apple cultivars ‘Golden Delicious’ and ‘King of the Pippins’. In order to get more information on the possible hormonal modes of action of these substances, fruit treated with thinning-agents were analysed for ethylene (C2H4), diffusable and extractable indoleacetic acid (IAA), abscisic acid (ABA) and gibberellin-like substances (GAs), and compared with water-treated controls.It is thought that the observed reduction in IAA transport is a major factor in the mode of action of all 3 thinning-agents investigated. Auxin transport may be affected directly by the chemicals or via a shift in the mobilizing ability of the treated fruits. The role of other hormones investigated is briefly discussed. 相似文献
129.
130.
A 14-month-old speyed female Boxer was presented with acute non-weight-bearing lameness in the right forelimb. Radiography revealed separation of the anconeal process, which was thence surgically removed. Histological examination of the anconeal process confirmed a primary fracture. Isolated unilateral anconeal process fracture in the dog is rare and this report includes histopathological findings of a primary anconeal fracture. 相似文献