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111.
Since the early 1970s the Indonesian Government has tried to establish marine nature reserves. The initial marine protected areas, however, have not been successful, due to lack of enforcement, and the present account is of a site on the western tip of Bali, where it is hoped that the idea will come to fruition. The marine resources of this Reserve, Bali Barat, are described, together with the various ways in which they are at present being exploited. The plan developed for the Reserve aims to prohibit destructive uses, while allowing those which are not as yet considered damaging to the area. The needs for strict protection of certain sites for tourism and for subsistence uses have been reconciled through a system of zones. The experience gained from Bali Barat should enable effective marine reserve conservation to be extended to other parts of the country, and the Reserve could also contribute directly to education of the public, and to research and management expertise. 相似文献
112.
Dener Márcio da Silva Oliveira Renato Paiva de Lima Matheus Sampaio Carneiro Barreto Ernst Eduard Jan Verburg Gustavo Conforti Ventura Mayrink 《Journal of Soils and Sediments》2017,17(1):1-10
Purpose
Land use change and soil management are frequently associated to land degradation and soil organic matter (SOM) losses in tropical regions. In Brazil, in order to avoid this process, different management strategies have been applied, such as no-tillage and agricultural disposal of swine manure (SM). This study was carried out to evaluate the quantity and quality of SOM, as well as the occurrence of nutrient accumulation in soils of areas under contrasting management systems that have received consecutive applications of SM over the last decades in Brazil.Materials and methods
Five land uses were sampled: native vegetation (NV), pasture with SM application (PA + SM), no-tillage with SM application (NT + SM), no-tillage (NT), and conventional tillage with SM application (CT + SM). Soil organic carbon (SOC), N, labile C, C management index (CMI), P, Ca2+, Mg2+, K+, Al3+, Fe, Zn, Mn, Cu, and H + Al were quantified.Results and discussion
Except for PA + SM, the agricultural land uses caused decreases in SOC contents comparing to NV. PA + SM showed the highest C stocks, 138.9?±?3.4 Mg ha?1 down to 0.4 m. The application of SM can be associated to the greater C stocks in PA + SM, NT + SM, and CT + SM and to the higher N contents in all land uses under this practice. Land uses which receive higher rates of swine manure application (PA + SM and CT + SM) have shown CMI greater than 100. However, this practice is associated to the accumulation of P, Cu, Na, and Zn in these soils.Conclusions
The SM application is associated to improvement on C stocks and SOM quality in area under pasture, no-tillage, and conventional tillage in Paraná State, Brazil. However, this practice is the main driver of nutrient accumulation in these areas.113.
Bovine thyroglobulin gene polymorphisms and their association with sexual precocity in Guzerat bulls
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ME Fernández AM Loaiza Echeverri M Henry M Drummond DA Andrade de Oliveira S Demyda Peyrás D Cunha Cardoso G Giovambattista JP Liron 《Reproduction in domestic animals》2017,52(5):911-913
Puberty is a stage of sexual development determined by the interaction of environmental factors and genetic mechanisms. Among them, thyroid function plays a key role in sexual development and spermatogenic function and is under the control of several genes, including the well‐described thyroglobulin gene (TG). Previous reports have shown genetic association between thyroid function and selected single nucleotide polymorphisms (SNPs) in taurine cattle. Therefore, the identification of genetic mechanisms involved in the regulation of this trait can assist with the selection for early pubertal bulls, thus improving genetic progress in livestock breeding. The aim of this study was to validate the association between TG SNPs and age at puberty in zebuine bulls. Three SNPs (rs110406764, rs109662686, rs109057985) were genotyped in 159 Guzerat animals using SEQUENOM technology. Results showed a significant association (p < .05) between the studied SNPs and puberty age, in agreement with our previous reports in a taurine breed. Interestingly, allele frequencies were different from those already reported, being GAT the most favourable allele for age at puberty in Guzerat (94.4 days lower). Overall, our findings corroborate previous reports and reinforce the importance of genetic influence in the regulation of sexual development and puberty through a thyroid pathway in zebuine cattle. 相似文献
114.
Effect of sperm pretreatment with glutathione and membrane destabilizing agents lysolecithin and Triton X‐100, on the efficiency of bovine intracytoplasmic sperm injection
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F Zambrano L Aguila ME Arias R Sanchez R Felmer 《Reproduction in domestic animals》2017,52(2):305-311
Intracytoplasmic sperm injection (ICSI) is an assisted reproduction tool with several applications. Its effectiveness in bovines is lower than that in other species, mainly because of difficulties in the decondensation of the sperm nucleus after injection, and the presence of the acrosome and the plasma membrane which remain intact in this procedure. In this study, we assessed the effect of lysolecithin (LL) and Triton X‐100 (TX), in combination with glutathione (GSH) as sperm pretreatments prior to ICSI. The GSH‐LL and GSH‐TX groups showed 0% of spermatozoa with intact membrane (SYBR 14+/PI), in comparison with the control (63.3%) and GSH (65.7%) groups. The proportions of spermatozoa with damaged acrosome membrane in the GSH‐LL, GSH‐TX, GSH and control groups were 46%, 35.9%, 10.5% and 7.5%, respectively. Sperm chromatin decondensation analysis showed that the groups incubated for 3 hr with GSH presented greater decondensation (p < .05). Although fertilization was improved in all treatment groups evaluated, no differences were observed in the cleavage rate 72 hr after activation in the GSH (73.7%), GSH‐LL (80.2%) and GSH‐TX (77.8%) groups compared to the control (66.3%), neither in the blastocyst rate on day 8 (24.0%, 26.2%, 27.1% and 28.4% for the control, GSH, GSH‐LL and GSH‐TX groups, respectively). No differences were also observed in the total number of cells in all groups. In conclusion, although these sperm treatments promoted nuclear decondensation and induced plasma membrane disruption, these effects were not sufficient to improve bovine embryonic development after ICSI. 相似文献
115.
RD Gama WL Vianna ME Pinese A de Campos Rosseto A de Sant''Anna Moretti 《Reproduction in domestic animals》2005,40(5):433-435
The use of hormonal protocols in puberty induction and synchronization of oestrus has lead to an increase in the efficiency of replacement gilts. The aim of this study was to evaluate different doses of porcine LH in precocious puberty induction and oestrus synchronization in a homogeneous group of gilts. Sixty-seven homogeneous prepubertal gilts (Camborough 22) at 137 +/- 4 days of age and 87 +/- 7 kg were treated with three different hormonal protocols: T1--600 UI of equine chorionic gonadotrophin (eCG; Novormon) and after a 72-h period 5 mg of LH (Lutropin); T2--600 UI of eCG and a 72-h period 2.5 mg of LH; T3--600 UI of eCG and a 72-h period 1.25 mg of LH. The ovaries were examined at slaughter, on day 6 after the hormonal treatment. There were no statistical differences (p > 0.05) between the different LH doses in the percentage of the detected oestrus (T1 = 42.85%; T2 = 60.87%, T3 = 52.18%), oestrus duration (T1 = 41.44 +/- 16.30 h; T2 = 48.57 +/- 16.29 h, T3 = 39.33 +/- 11.42 h), number of corpora lutea (T1 = 9.61 +/- 5.43; T2 = 9.86 +/- 3.32, T3 = 8.13 +/- 5.52) and percentage of animals presenting ovarian cystic degeneration (T1 = 33.33%; T2 = 39.13%, T3 = 39.13%). The T2 (2.5 mg of LH) presented the lowest dispersion (p < 0.05) of the LH-ovulation interval (T1 = 37.17 +/- 4.07 h; T2 = 38.26 +/- 2.84 h; T3 = 36.25 +/- 5.69 h). The LH dose reduction to 2.50 and 1.25 mg presented equal results with the recommended dose of 5.0 mg, and could be used in the precocious induction of oestrus in gilts. The 2.5-mg LH dose showed the lowest dispersion of ovulation and it can be used in fixed-time artificial insemination programmes. 相似文献
116.
A Ortega-Pacheco ME Bolio-González RF Colin-Flores CH Sauri-Arceo E Gutiérrez-Blanco M Jiménez-Coello C Linde Forsberg 《Reproduction in domestic animals》2006,41(3):227-232
A Burdizzo castrator was evaluated for the neutering of dogs. Histological and morphological changes of spermatic cells and peripheral serum testosterone after challenge with a GnRH-analogue (gonadorelin) were assessed. There was a control group (G1), a surgically castrated group (G2) and a Burdizzo group (G3) divided in two, G3a receiving two crunches in each spermatic cord and G3b receiving one crunch in each spermatic cord. Sixteen days after application of the Burdizzo blood samples were taken from the dogs at 30 min interval during 2 h; after the second sample the dogs were treated with 1 mug/kg body weight of gonadorelin i.v. The same protocol of gonadorelin challenge was performed in G1 and G2 dogs. The G2 dogs were surgically castrated after the second blood sample, before the gonadorelin treatment, and the G1 dogs after the last blood sample. The excised gonads were examined histologically, and sperm smears were prepared from the caudae epididymidis. The testes and plexus pampiniformis of the G1 and G2 dogs had a normal histological appearance, and they had morphologically normal epididymal sperm cells. In all G3 dogs, there was an acute fibrosis with an inflammatory reaction in the plexus pampiniformis. The testes from the G3a dogs showed diffuse areas of infarction and degeneration of the parenchyma. Similar but less diffuse lesions were seen in group 3b dogs. The deferent ducts from all G3 dogs showed vasitis and/or sperm granulomas. Azoospermia or sperm malformations were observed in the epididymal smears from the G3 dogs. Testosterone concentration in the G1 dogs increased after gonadorelin application (p < 0.0001). The G2 dogs had basal testosterone levels after castration (p < 0.001) and did not respond to gonadorelin. Groups 3a and b showed a slight but non-significant increase in testosterone concentration after gonadorelin challenge, supposedly due to the reduction of testicular blood flow and loss of testicular interstitial tissue. 相似文献
117.
L. J. FREEMAN DVM MS G. A. HEGREBERG DVM PhD J. D. ROBINETTE DVM MS DiplomateACVs J. T. KIMBRELL MS ME 《Veterinary surgery : VS》1989,18(2):97-102
The biomechanical properties of wounded and nonwounded skin were studied in three dogs and three cats affected with type I Ehlers-Danlos syndrome. Three nonaffected dogs and one nonaffected cat served as controls. Samples of wounded skin and adjacent normal skin were harvested at days 75, 138, 141, 144, 147, and 150. Samples were subjected to uniaxial tensile strength testing. Tensile strength, energy absorbed, and site of failure were recorded. In the dogs with Ehlers-Danlos syndrome, there was an increase in tensile strength in samples containing a scar over adjacent intact skin. In nonaffected dogs, affected cats and the nonaffected cat, the nonwounded skin samples had greater tensile strength. The energy absorbed by the skin samples during testing was highly correlated with tensile strength. 相似文献
118.
Haematological and biochemical reference values were established from 45 clinically healthy koalas. Statistical analysis revealed no significant differences for sex and season of sampling. Immature koalas had significantly higher alkaline phosphatase and inorganic phosphate values, and significantly lower total protein concentrations due to low globulins values. Enzyme reference values tended to be wide and could limit their usefulness in detecting disease. In the reference values for leukocytes, neutrophils and lymphocytes, the inclusion of low values which were not actually seen may interfere with the detection of reduced levels due to disease. 相似文献
119.
Effects of density and period of competition by Solanum nigrum L. on direct seeded tomatoes in relation to weed control The effects of density and period of competition from Solanum nigrum L. were measured in direct seeded tomatoes given weed control treatments currently used in south-east France. S. nigrum emerging after a diquat treatment at the 2–3 leaf stage of the crop and thinned to low densities (<12.8 plants ha?1) at the 5–6 leaf stage of the crop caused significant yield loss if left to compete with the crop until harvest. Yield reduction was smaller if the same weed densities were present only until the onset of flowering. The regression curves of yield on weed density differed as annual climatic variations affected sowing date and plant growth; a comparison between years was made using the relation ‘crop yield × weed biomass/crop biomass’. Significant interactions between weed density and period of competition were found with yield of both green and red fruit. For late sown crops with low densities of S. nigrum two weed control treatments at the 5–6 leaf stage and at the onset of flowering were sufficient to prevent yield loss. 相似文献
120.
Moriel Philipe Vendramini Joao M. B. Carnelos Caio Piccolo Matheus B. da Silva Hiran M. 《Tropical animal health and production》2019,51(2):339-344
Tropical Animal Health and Production - The objective of this study was to evaluate the effects of monensin on performance of beef heifers fed warm-season forages. Brangus heifers... 相似文献