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101.
102.
Objective To determine the effect of a long-acting local anaesthetic on the plasma cortisol response in calves dehorned using a scoop.
Design A physiological study with controls.
Procedure Seventy female calves, 3 to 4 months old, were divided into seven groups and dehorned by scoop with or without a long acting local anaesthetic (bupivacaine) which provides local anaesthesia for 3 to 4 h. In some treatment groups the local anaesthetic was given a second time, after 4 h, to give 8 h of anaesthesia. Blood samples were taken before and for 9 h after treatment and plasma cortisol concentrations were measured.
Results Scoop dehorning caused a marked rise in plasma cortisol concentration, which returned to pre-dehorning values after 7 h. The cortisol concentrations of calves given bupiva-caine were similar to those of control animals for 4 h after dehorning, but then a significant and protracted rise occurred, with concentrations returning to pretreatment values at about 9 h after dehorning. In calves given a second treatment of bupivacaine 4 h after dehorning, the plasma cortisol concentration remained similar to control values for 8 h after dehorning but then increased sharply.
Conclusions During its period of activity long-acting local anaesthetic prevented the rise usually seen after scoop dehorning in plasma cortisol concentrations; by inference it also alleviated the pain-induced distress caused by this procedure. However, when its effects had worn off the plasma cortisol values rose sharply indicating that animals still experienced pain-induced distress despite local anaesthetic being administered.  相似文献   
103.
The screw-worm Cochliomyia hominivorax (Coquerel), whose larvae develop in wild and domestic animals as well as in man, is one of the major causes of myiasis in Brazil. Sheep raising is expanding in the state of São Paulo, where information about the infestation of screw-worm is necessary for appropriate control measures. The present data were obtained from questionnaires sent to all sheep breeders belonging to Associação Paulista de Criadores de Ovinos – ASPACO (São Paulo State Association of Sheep Breeders). Response reliability was tested by random visits paid to 10.6% of the respondents. The results show that screw-worm is the most frequent ectoparasite in the flocks and is responsible for the greatest economic losses. Its occurrence is strongly associated with flock size, reaching 100% in flocks consisting of more than 500 animals. Infestation is higher in spring and summer and lowest in the fall. The number of cases increases in the presence of some management practices such as tail amputation. Furthermore, several other associations between the indicators surveyed were also found to be significant. The data obtained will permit the elaboration of strategies for the control of this parasitosis.  相似文献   
104.
Seventy-four dogs from the State of Rio de Janeiro with ulcerated cutaneous lesions were submitted to clinical, dermatological, parasitological, mycological, histopathological and cytopathological exams, a leishmanin skin test, an indirect immunofluorescence (IIF) test for leishmaniosis, and nonspecific laboratory tests such as blood count and serum biochemistry. Sporothrix schenckii was isolated from 41 dogs and Leishmania (Viannia) braziliensis was isolated from 33 animals. Most dogs with sporotrichosis were from the municipality of Rio de Janeiro (53.7%) and presented ulcerated cutaneous lesions on the head (68.3%). Laboratory alterations in these animals included anemia (58.5%), hypoalbuminemia (83%) and hyperglobulinemia (75.6%). Histopathology revealed the predominance of a chronic granulomatous inflammatory infiltrate (70.7%), and yeast-like structures were detected in 17% of the histopathological exams and in 32% of the cytological exams. Three of 41 dogs with sporotrichosis were seropositive by IIF for leishmaniosis and 2 of 20 animals tested within this group had a positive leishmanin skin test. Similarly, most of the 33 dogs with leishmaniosis were from the municipality of Rio de Janeiro (69.7%) and had ulcerated cutaneous lesions on the head (84.8%). Laboratory alterations in these animals included anemia (66.7%), hypoalbuminemia (100%) and hyperglobulinemia (91%). Histopathology showed the predominance of a chronic granulomatous inflammatory infiltrate (63.6%) and amastigote forms were detected in 30.3% of the histopathological exams and in 31.8% of the 22 cytological exams performed. About 72.7% of the dogs were seropositive by IIF and five of seven animals had a positive skin test. Due to the clinical similarities, histopathological and nonspecific laboratory results similarities, the serological and skin tests for leishmaniosis positive in dogs with sporotrichosis, and the overlapping endemic areas in Rio de Janeiro, the differential diagnosis between the two diseases requires the demonstration of their respective etiological agents.  相似文献   
105.
Cyprinid herpesvirus 3 (CyHV-3), the causative agent of koi herpesvirus disease, is a major threat for carp populations in many countries worldwide, including Indonesia. It has been shown that many genotypes circulate worldwide, all highly related to one of the two known lineages U/I and J. In this study, we evaluated the spatial and temporal distribution of CyHV-3 strains in a small enzootic area, the lake of Cirata (West Java, Indonesia). Of the 365 samples analysed, from clinical or asymptomatic fish, 244 were found positive for CyHV-3, suggesting a high occurrence of the virus. Genotyping of these viral specimens with a range of molecular markers revealed the presence of numerous haplotypes in the host population, all related to the J lineage. In single individuals, mixed-genotype infections occurred at high frequency. The present results demonstrate that polymorphic molecular markers are suitable to monitor the genetic evolution of a viral population in an enzootic area.  相似文献   
106.
三峡库区坡耕地粮经果复合垄作对土壤水分特征的影响   总被引:1,自引:0,他引:1  
减缓、减轻干旱的发生与危害是三块库区坡耕地持续利用的关键.在坡度15°标准径流小区,以聚土垄作和农林复合为基本方法,营建坡耕地粮经果复合垄作模式,并对模式的土壤水分状况进行了长期定位观测.2002~2005连续4年试验结果表明,粮经果复合垄作能有效改善坡耕地土壤结构,利于土壤保持适宜的透水性和持水性,土壤有效库容扩大了145.2 m3/hm2;同时,增加了土壤贮水,提高了贮水利用率,尤其是底层贮水利用率,比较平作对照,贮水库客和贮水利用率分别增大了5.73%、5.32%;此外,垄沟拦蓄了地表径流,减少径流损失达74.18%~95.81%,有利于降水入渗补给及旱季底墒的保护.  相似文献   
107.
This study aimed to evaluate the effect of the exogenous recombinant bovine somatotropin (rbST) on plasma concentrations of insulin‐like growth factor I (IGF‐I), insulin and semen quality of bulls. Twenty bulls (Aberdeen Angus and Brangus) were divided by breed into two groups. Placebo group was injected with NaCl 0.9% (s.c.) and treatment group with rbST (s.c., 500 mg) at days 0 and 14 of the experiment. Immediately after semen collection, blood samples were taken on days 0, 14, 28, 42 and 56 of the experiment. Semen was also collected on day 70 of the experiment. Evaluation of sperm motility was performed at pre‐freezing and post‐thawing stage, whereas assessment of sperm membrane integrity was performed after freezing and thawing. Analysis of data revealed that the effect of treatment and treatment‐by‐collection day on plasma concentrations of IGF‐I and insulin was not significant. However, mean plasma concentrations of IGF‐I and insulin were affected (p < 0.0001) by days of blood sampling. Effect of treatment and treatment‐by‐collection day on motility of spermatozoa was similar (p > 0.05) at pre‐freezing and post‐thawing stage. Intactness of plasmalemma and tail membrane of spermatozoa at post‐thawing stage was higher (p < 0.05) in rbST‐treated group than in control. In conclusion, rbST did not affect plasma concentrations of IGF‐I and insulin, however, it did improve post‐thaw sperm membrane integrity.  相似文献   
108.
Growth and nutritional status of young plants of Eucalyptus were assessed in a field trial, under different scenarios of harvest residue management and nutrient availability. Treatments were as follows: incorporation of harvest residues into the soil by harrowing (I); I with N fertiliser application (IF); I with leguminous, Lupinus luteus L., seeding (IL); removal of harvest residues (R); R with N fertiliser application (RF); R with leguminous seeding (RL); distribution of harvest residues on the soil surface (S); S with N fertiliser application (SF). Treatments were replicated four times in four blocks with a fully randomised design. Tree growth (height and diameter at breast height) was measured and understory biomass destructively recorded. Tree nutritional status was assessed by foliar analysis (N, Ca, Mg, P, K and leaf area). Significant differences in growth between I, R and S treatments were only detected at early stage. Intercropping with Lupinus decreased tree growth during the early phase, but after 5 years growth was similar to that measured in the I and R treatments. Application of fertiliser enhanced tree growth especially when harvest residues were retained on the soil surface. Combining incorporation of harvest residues with fertiliser application (IF) was the best option to increase tree growth, which was significantly greater than in the R and S. Initially, leaf N was positively affected by the leguminous (RL and IL), but, after the first fertiliser application (1 year after planting), greater N was observed in the IF, RF and SF, the difference decreasing gradually over the following years.  相似文献   
109.
  • ? Chestnut stands (Castanea sativa Mill.) for fruit production, in Northern Portugal, are subjected to frequent soil tillage operations, which is considered a threat for the system sustainability.
  • ? The effects of replacement of conventional tillage by the no-tillage system in chestnut stands on decomposition and nutrient dynamics of leaf litter and burs were evaluated, using the litterbag methodology. Amounts of mass and nutrients in the organic layers, and chemical characteristics of the 0–20 cm top soil layer were assessed after eight years.
  • ? The mass loss and release of N, P, Ca and Mg from both leaves and burs buried in the soil were faster than from those placed on the soil surface. Burs decomposed and released nutrients more slowly than leaf litter. The no-tillage system led to the formation of organic layers, which retained great amounts of N (249.2 kg ha?1) and Ca (215.5 kg ha?1). Such a management system increased the concentration of organic C and nutrients in the 0–5 cm top soil layer, but significant differences were only observed for exchangeable Ca.
  • ? The no-tillage system may enhance organic C accumulation regarding the conventional system, due to the increment in both organic and mineral soil layers.
  •   相似文献   
    110.
    Effects of harvest residues on nutrient leaching and soil chemical properties were studied in a lysimeter experiment. Treatments were: (A) forest floor litter and harvest residues, other than branches, incorporated into the soil, (B) as A, but with branches cut in 20 cm long bits and placed on the soil surface, (C) as B, but with bits incorporated into the soil, (D) as B, but with branches chopped into chips, (E) as C, but with branches chopped into chips, (F) forest floor litter and harvest residues on the soil surface, with branches cut in 20 cm long bits, (G) as F, but with branches chopped into chips, and (H) absence of harvest residues (control). Treatments were applied in zero-tension lysimeters containing 25 kg of soil. Leachates were collected for a 6-year period. At the end of the experiment, lysimeters were dismantled and soil was divided in four layers. Residues, other than branches, increased N leaching, as compared with the control. Branches on the soil surface reduced N leaching when cut in chips. Branches incorporated into the soil reduced leaching independently of their size. Organic residues on the soil surface showed similar effect to those incorporated into the soil. However, harvest residues on the soil surface increased leachate volume, and reduced Ca and P losses. Such a placement of residues led to high contents of Ca and P in the 0–5 cm top soil layer. Contents of organic C, total N and base cations were not affected by the treatments.  相似文献   
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