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421.
Acupuncture has been shown to have the beneficial effect of reducing stress responses in animals and humans. Pharmacopuncture is the injection of subclinical doses of drugs into acupoints to give therapeutic results without side effects. This study compared the effects of injecting the usual dose of acepromazine (ACP; 0.1 mg/kg, intramuscularly [I.M.]) with those of pharmacopuncture (1/10 ACP dose at the governing vessel 1 [GV 1] acupoint) on the stress responses of healthy horses undergoing road transport for 2.5 hours. Four different treatments were applied immediately before loading, with 8 animals/treatment: injection of saline or ACP (0.1 mg/kg, I.M.) at the base of the neck; and injection of saline or 1/10 ACP (0.01 mg/kg) at the GV 1 acupoint. The road transport increased heart rate (HR), respiratory rate, body temperature, and serum cortisol of the untreated horses (injected with saline at the base of the neck). Pharmacopuncture at GV 1 reduced the average HR and transport-induced increase in HR at unloading, without changing the other variables. On the other hand, ACP (0.1 mg/kg) produced significant sedation and reduced the transport-induced increase in respiratory rate but without preventing the stress-induced increase of cortisol. Other acupuncture points and drugs should be tested to verify the beneficial effect of this therapy to reduce stress in horses during road transport.  相似文献   
422.
Summary The antinutritional factors found in soybean, lectin (SBL) and Kunitz trypsin inhibitor (SKTI), are usually inactivated by heat treatment. However, residual activity of these factors can be found in several types of soy-derived products. Heat treatment does not completely eliminate these factors, and in addition it may considerably decrease protein solubility. The genetic elimination of these antinutritional factors could be an alternative to the heat treatment. This study aimed to develop soybean lines devoid of SKTI and SBL in their seeds. The population under study was obtained by crossing the normal cv. Monarca with a soybean line lacking SKTI and SBL. Specific DNA primers were designed for the identification of the recessive alleles that condition the absence of SKTI and SBL. F2 seeds presenting the DNA markers that identify the recessive alleles were selected and the corresponding F2 plants were backcrossed with the recurrent parent (‘Monarca’), producing the BC1F1 generation. The F2 generation was analyzed by SDS-PAGE in order to confirm the genotypes of the F2 selected. The segregation tests confirmed that these traits are governed by two genes that segregate independently.  相似文献   
423.
Small ruminant lentiviruses (SRLV) infect the monocyte/macrophage lineage inducing a long-lasting infection affecting body condition, production and welfare of sheep and goats all over the world. Macrophages play a pivotal role on the host’s innate and adaptative immune responses against parasites by becoming differentially activated. Macrophage heterogeneity can tentatively be classified into classically differentiated macrophages (M1) through stimulation with IFN-γ displaying an inflammatory profile, or can be alternatively differentiated by stimulation with IL-4/IL-13 into M2 macrophages with homeostatic functions. Since infection by SRLV can modulate macrophage functions we explored here whether ovine and caprine macrophages can be segregated into M1 and M2 populations and whether this differential polarization represents differential susceptibility to SRLV infection. We found that like in human and mouse systems, ovine and caprine macrophages can be differentiated with particular stimuli into M1/M2 subpopulations displaying specific markers. In addition, small ruminant macrophages are plastic since M1 differentiated macrophages can express M2 markers when the stimulus changes from IFN-γ to IL-4. SRLV replication was restricted in M1 macrophages and increased in M2 differentiated macrophages respectively according to viral production. Identification of the infection pathways in macrophage populations may provide new targets for eliciting appropriate immune responses against SRLV infection.  相似文献   
424.
An understanding of factors influencing the decision of rural people to keep sheep and/or goats is crucial when formulating technologies and policies that support village-based small ruminant production. The knowledge of such factors will also improve assessment of impact intervention strategies on the livelihoods of rural people. Structured questionnaires administered in 228 households were used to study the ownership patterns of small ruminants in southern Benin. The ownership of goats was higher (91%) than sheep (35%) because goats are not affected by any ethnic or cultural restrictions. Goats are also perceived to be a less risky to invest into compared to sheep. Women represented 71% of the keepers of goats. Predictive models of ownership were developed using logistic regression. The results showed that younger household members (p < 0.05) especially young women (60%) are more likely to own small ruminants. Owners of small ruminants are less likely to be involved in off-farm activities and would often have no access to credit facilities. Gender, ethnicity, and perception of risk associated with species are the major factors affecting people’s choice of species. These findings highlight the financing and insurance roles that small ruminants, particularly goats, are playing in the study area. In order to develop suitable technologies and formulate policies to improve productivity and enhance livelihoods, the constraints to goat production need to be identified, and the local knowledge of the keepers should be investigated.
Luc Hippolyte DossaEmail: Email:
  相似文献   
425.
The aim of the study was to evaluate the potential impact of grazing on the control of Mimosa pudica, a ligneous weed species that invades grasslands in French Guiana. Three experiments were conducted in a glasshouse to test the potential impact of: (i) shading by testing different Photsynthetically Active Radiation (PAR) fluxes on seedlings and (ii) cutting of juveniles, at three stages of development, on their survival, flowering rate and nutritive value as measured by the mass:length ratio of stems and by branching processes. A significant mortality rate (0·20) was obtained only for seedlings at the cotyledon stage when the PAR flux was reduced proportionately by 0·83. Shading reduced both flowering rate and mass:length ratio of stems. For seedlings at the cotyledon stage, the flowering rate decreased from 0·85 for the control to zero for the low light treatment (0·13 of PAR flux of the control treatment). The mass:length ratio of stems of seedlings in the low light treatment was reduced to 0·20 of that of control seedlings, at the fifth‐leaf stage. Cutting treatment had no effect on mortality of juvenile plants whatever the size of the juvenile plant. The proportion of juvenile plants flowering was high for all cutting treatments. It is suggested that regular, but not continuous grazing, could maintain a dense sward to limit recruitment by seedling establishment and seed production, and maintain branched and juvenile plants with a high‐nutritive value at the seedling stage.  相似文献   
426.
Heat tolerance in Brazilian sheep: Physiological and blood parameters   总被引:1,自引:1,他引:0  
Thirty Santa Ines adult, non-lactating, non-pregnant ewes, ten with a brown coat, ten black coated and ten white coated, as well as ten Bergamasca and ten of mixed breed were used to evaluate the effect of climate on physiological and blood parameters in sheep. Two sample collections were taken (6 am and 2 pm) on six days. Sweating rate (SR), heart (HR) and breathing rates (BR), complete hemogram, rectal (RT) and skin temperatures (ST) were measured. Variance analyses were carried out using SAS®. In general, there were significant differences between animals due to skin type, time and day of collection. White coated animals showed lower HR, BR and RT, with afternoon parameters higher than morning. Correlations between HR, BR, RT, SR and ST were medium and positive. Correlations between physiological and blood traits were in general negative and medium. Packed Cell Volume (PCV), total plasma proteins, red blood cell count and hemoglobin concentration had high positive correlations between each other. The first two autovectors explained 49% of variation between traits. White coated Santa Ines animals were shown to be better adapted to climatic conditions in Central Brazil and wool sheep more affected by heat.  相似文献   
427.
Active hepatitis E virus (HEV) infections in two Brazilian swine herds were investigated. In study 1, 26 piglets born to five anti-HEV positive sows were monitored from birth to post-partum week 22. Serum samples were screened for the detection of anti-HEV antibodies and a nested RT-PCR used to examine the HEV genome. Passive transfer of immunity was confirmed. At week 22, 23/26 (88.4%) of the piglets had seroconverted. Genome amplification was achieved in a feces pool from one holding pen and in one serum sample, both from 13-week-old animals. Histology was suggestive of a potential HEV infection. In the second study, 47 piglets born to six anti-HEV-positive sows were monitored after weaning. Seroconversion was determined in eight animals at 6-8 weeks of age. HEV RNA was detected in two pools from a holding pen for 12-16-week-old animals. Brazilian isolates were classified as genotype 3. This is the first molecular evidence of HEV infection in Brazilian pig herds.  相似文献   
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