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1.
河南县是纯牧业县,畜牧是其支柱产业,也是牧民群众赖以生存和生活的物质基础,主要饲养牦牛、欧拉羊。而牛羊体内和体表常寄生各种寄生虫,包括寄生于消化道的圆线虫,如寄生于第四胃和小肠的毛圆线虫,最常见的捻转血毛浅虫、食道口线虫、仰口线虫等,绦虫和吸虫,还有寄生于体表的蜱螨等,它们与宿主争夺营养物质,破坏天然防御屏障,引发各种继发性传染病,进而严重影响养牛、养羊业的经济效益。牛、羊寄生虫病的程序化防治是一项综合性防治新技术。它改变过去传统的防治方法,改单一寄生虫防治为主要寄生虫的有序防治,使牛羊群中的寄生虫得到全面驱…  相似文献   

2.
Summary

Anti‐bovine lymphocyte serum (ABLS) had been prepared in horses with calf thymocytes as antigen and its effects in calves following parenteral administration were studied. The optimal dose was found to be one ml/kg body weight. The A BLS suppressed both the T and B cell functions. The former was indicated by the disturbed response to sheep erythrocytes injections, by the decreased number of spontaneous E rosette forming lymphocytes, the prolonged survival of skin allografts and the significant inhibition of the delayed hypersensibility skin reaction (tuberculination) following administration of Mycobacterium microti. The latter was based on the disturbed response to a subcutaneous dose of tetanus toxoid. The reaction of lymphocytes of ABLS treated calves to phytohemagglutinin and poke weed mitogen was also inhibited. The disturbed reactions of the T and B cells might be among others based on the strong reduction of lymphocytes in the blood circulation by ABLS (up to 10–20%).

Suggestions with regard to further applications and studies with ABLS were given.  相似文献   

3.
A trial was conducted during the anestrous period in female goats to determine: (a) whether estrus can be induced in anestrous goats by administration of equine chorionic gonadotropic hormone (eCG) and PGF2α under pen conditions and (b) whether these sexually active female goats can elicit sexual arousal in sexually inactive bucks. One hundred and fifteen pluriparous, nonlactating mixed-breed female goats were randomly assigned to one of four treatment groups: (1) administration of a single dose of 240 IU of eCG, 50 μg PGF2α i.m., and 25 mg progesterone (P4) (eCG; n?=?30); (2) administration of P4 and exposure to female goats treated with eCG–PGF2α (P4; n?=?39); (3) administration of 0.5 ml saline and P4 (Sal; n?=?23); and (4) P4 plus exposure to female goats treated with saline (Con; n?=?23). After hormone administration, all goats were put together with adult sexually inactive bucks for 15 days. The percentage of goats in estrus during these 15 days was similar in eCG-treated animals and untreated animals exposed to the eCG animals (97 and 95 %). Pregnancy rate was also similar (63 vs. 64 %) between these two groups. eCG-treated goats exhibited estrus earlier (P?<?0.05) than the treated goats in contact with the eCG goats. Furthermore, eCG-treated goats had larger litters (1.9?±?0.2 vs. 1.6?±?0.1, P?<?0.05) than the untreated goats in contact with the eCG goats. These results show that fertile estrus can be induced in anestrous female goats by exposing them to female goats induced to estrus with eCG. This female–female interaction triggers the stimulation cycle leading to the sexual arousal of bucks.  相似文献   

4.
Background:This study was conducted to investigate effect of exogenous melatonin on the development of mouse mature oocytes after cryopreservation.Results:First,mouse metaphase Ⅱ(MII) oocytes were vitrified in the open-pulled straws(OPS).After warming,they were cultured for 1 h in M_2 medium containing melatonin at different concentrations(0,10~(-9),10~(-7),10~(-5),10~(-3)mol/L).Then the oocytes were used to detect reactive oxygen species(ROS) and glutathione(GSH) levels(fluorescence microscopy),and the developmental potential after parthenogenetic activation.The experimental results showed that the ROS level and cleavage rate in 10~(-3) mol/L melatonin group was significantly lower than that in melatonin-free group(control).The GSH levels and blastocyst rates in all melatonin-treated groups were similar to that in control.Based on the above results,we detected the expression of gene Hsp90aa1,Hsf1,Hspa1 b,Nrf2 and Bcl-x1 with qRT-PCR in oocytes treated with 10~(-7),or 10~(-3) mol/L melatonin and untreated control.After warming and culture for 1 h,the oocytes showed higher Hsp90aa1 expression in 10~(-7) mol/L melatonin-treated group than in the control(P0.05);the Hsf1,Hsp90aa1 and Bcl-x1 expression were significantly decreased in 10~(-3) mol/L melatonin-treated group when compared to the control.Based on the above results and previous research,we detected the development of vitrified-warmed oocytes treated with either 10~(-7) or 0 mol/L melatonin by in vitro fertilization.No difference was observed between them.Conclusions:Our results indicate that the supplementation of melatonin(10~(-9) to 10~(-3) mol/L) in culture medium and incubation for 1 h did not improve the subsequent developmental potential of vitrified-warmed mouse MII oocytes,even if there were alteration in gene expression.  相似文献   

5.
1.?The purpose of this study was to investigate the protective effect of α-lipoic acid (LA) on aflatoxin (AF) toxicosis in chicks.

2.?Groups of 10 Ross PM3 chicks were given, for 21 d, no AF (C), 60 mg/kg/bwt of α-lipoic acid (LA), 150 ppb of aflatoxin (AF1), 150 ppb of aflatoxin plus 60 mg/kg/bwt of α-lipoic acid (AF1 + LA), 300 ppb of aflatoxin (AF2), and 300 ppb of aflatoxin plus 60 mg/kg/bwt of α-lipoic acid (AF2 + LA). Before the animals were killed, blood samples were drawn for haematological analysis, and then tissue samples were collected for histopathological investigation. Immunohistochemical staining was performed against inducible nitric oxide synthase (iNOS) and nitrotyrosine on liver samples. Apoptotic cell death in liver was assessed by in situ TUNEL assay. The malondialdehyde (MDA) and reduced glutathione (GSH) concentrayions in liver and kidney were also determined.

3.?Hydropic degeneration and occasional necrosis, bile duct hyperplasia and periportal fibrosis were observed in the livers of AF-treated groups. The severity of these changes was reduced in LA-supplemented AF groups. Occasionally, thymic cortical atrophy, lymphoid depletion in spleen and bursa of Fabricius, and degeneration in the kidney tubule epitheliums were detected in AF groups. The severity of these degenerative changes was slightly reduced in LA supplemented groups.

4.?There was moderate to strong iNOS and nitrotyrosine immunoreactivity in the livers of AF groups, while decreased immunoreactivity was observed against both antibodies in the LA supplemented groups. Apoptotic cells were numerous in the AF groups, while greatly reduced in LA supplemented groups.

5.?In the liver and kidney of AF-treated groups given 300 ppb of aflatoxin, MDA concentrations were increased as GSH decreased, compared to the control group. LA supplementation of AF-treated birds improved the results compared to the AF only groups, however a statistical difference was observed only in liver tissues between AF2 + LA and AF2 groups. Haematological variables showed no differences among the groups.

6.?In conclusion, supplementation of feed with the antioxidant LA, might ameliorate the degenerative effects caused by aflatoxin due to lipid peroxidation.  相似文献   


6.
Background: Estradiol(E2) is required for luteolysis in cows and its injection stimulates prostaglandin F2α(PGF2α)release. The main goal of our study was to investigate the ability of endometrial explants and cells treated with E2 and the calcium ionophore(CI) A23187 to synthesize PGF2α.Results: Treatment with E2 in vivo resulted in a 48.4% increase of PGF2α production by endometrial explants treated in vitro with A23187. Production of PGF2α was better stimulated with A23187 at concentrations of 10-6and10-5mol/L compared with other concentrations used. The concentration of PGF2α for untreated bovine endometrial cell cultures was 33.1 pg/m L, while for cultures treated with E2, A23187, or a combination of E2 and A23187, the PGF2α concentration was 32.5, 92.4 and 145.6 pg/m L, respectively.Conclusions: Treatment with A23187 tended to stimulate PGF2α production. In the presence of E2, A23187 significantly stimulated PGF2α synthesis. It appears that A23187 potentiates the effects of E2 with respect to synthesis of endometrial PGF2α in cattle.  相似文献   

7.
ObjectiveTo evaluate the effect of a romifidine infusion on antinociception and sedation, and to investigate its relationship with plasma concentration.Study designProspective, experimental, nonrandomized trial.AnimalsA total of 10 healthy adult warmblood horses.MethodsRomifidine (loading dose: 0.08 mg kg–1, infusion: 0.03 mg kg–1 hour–1) was administered intravenously over 120 minutes. Romifidine plasma concentrations were determined by capillary electrophoresis. Sedation quality and nociceptive thresholds were evaluated at regular time points before, during and after romifidine administration. The nociceptive withdrawal reflex was elicited by electrical stimulation at the thoracic limb using a dedicated threshold tracking algorithm and recorded by electromyography at the deltoid muscle. A pharmacokinetic–pharmacodynamic model was established and correlation between romifidine plasma concentration and main output variables tested.ResultsA two compartmental model best described the romifidine pharmacokinetic profile. The nociceptive thresholds increased compared with baseline in all horses from 10 to 146 minutes after romifidine administration (p < 0.001). Peak effect reached 5.7 ± 2.3 times the baseline threshold (mean ± standard deviation). The effect/concentration relationship followed a counter-clockwise hysteresis loop. The mean plasma concentration was weakly correlated to nociceptive thresholds (p < 0.0071, r = 0.392). The sedative effects were significant until 160 minutes but variable, not correlated to plasma concentration (p = 0.067), and weakly correlated to nociceptive thresholds (p < 0.0001, r = 0.33).Conclusions and clinical relevanceRomifidine elicited a marked antinociceptive effect. Romifidine-induced antinociception appeared with a delayed onset and lasted longer than sedation after discontinuing its administration.  相似文献   

8.
From 1989 until 2003, the Swedish Sheepdog Society used a standardized method, Herding Trait Characterization (HTC), to describe herding behavior of individual Border collies for breeding purposes. In the HTC, which existed in 2 consecutive versions, the dog’s herding behavior was described using predefined scales typically consisting of 6 classes within each trait. In total, 1,663 dogs participated in the first version and 951 in the second. The main difference between the versions was the structure of the protocols used to record the traits. In the first version, the scales were designed to describe the intensity in the expression of the measured traits. In the second version, the most desirable behavioral expression was placed in the middle of the scale. Another difference was that in the second version, the judges were given more freedom for their own interpretations, that is, the scales were more subjective. The objective of this study was to examine the quality of each version from a breeding perspective, and to analyze the reasons for possible differences in this respect between them. Heritability estimates for the 17 traits of the earlier version of the HTC ranged from 0.14 to 0.50 (weighted average: 0.30), all significantly different from 0. Corresponding heritabilities for the 19 traits in the later version were substantially lower (0.03-0.41, weighted average: 0.16), 3 of them not being significantly different from 0. Owing to the moderate-to-high heritabilities for the traits measured in the earlier version of the HTC, it would be possible to accomplish effective selection of breeding animals for most of the measured traits. It is plausible that the less neutral and more subjective protocol of the later version is the main cause for the lower heritabilities.  相似文献   

9.

Background

Estradiol (E2) is required for luteolysis in cows and its injection stimulates prostaglandin F2α (PGF2α) release. The main goal of our study was to investigate the ability of endometrial explants and cells treated with E2 and the calcium ionophore (CI) A23187 to synthesize PGF2α.

Results

Treatment with E2in vivo resulted in a 48.4% increase of PGF2α production by endometrial explants treated in vitro with A23187. Production of PGF2α was better stimulated with A23187 at concentrations of 10-6 and 10-5 mol/L compared with other concentrations used. The concentration of PGF2α for untreated bovine endometrial cell cultures was 33.1 pg/mL, while for cultures treated with E2, A23187, or a combination of E2 and A23187, the PGF2α concentration was 32.5, 92.4 and 145.6 pg/mL, respectively.

Conclusions

Treatment with A23187 tended to stimulate PGF2α production. In the presence of E2, A23187 significantly stimulated PGF2α synthesis. It appears that A23187 potentiates the effects of E2 with respect to synthesis of endometrial PGF2α in cattle.  相似文献   

10.
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11.
1. Reserpine was found to inhibit the secretion of luteinising hormone when injected into intact and gonadectomised fowl at a dose rate which caused heavy sedation.

2. This could indicate that reserpine or its derivatives should not be used for breeding poultry.  相似文献   


12.
ObjectiveFactors described as contributors to the ‘penumbra effect’ in relation to pulse oximetry include optical shunting, circulatory anastomoses and probe parallelity. This study aimed to clarify the main underlying mechanism involved.Study designProspective clinical trial.AnimalsA total of 30 dogs and 15 cats (client-owned).MethodsIn anaesthetized dogs and cats, a pulse oximeter probe was placed on the tongue to measure haemoglobin oxygen saturation (SpO2) and perfusion index. In 15 dogs, the probe was positioned at the root (baseline) of the tongue, then at 0.5 and 1 cm rostral to it, to investigate the effect of circulatory anastomoses on SpO2 values. In cats (which do not have lingual arteriovenous anastomoses), the probe was positioned at the root and apex of the tongue. To assess the effect of probe parallelity on SpO2 values in dogs, two lines were drawn parallel to the planes of the light-emitting diode and the detector surfaces and the intersection angle calculated using ImageMeter Pro, Google Play. In a further 15 dogs, the probe was placed at the tongue edge (0% optical shunt), with 50% optical shunt, then with the 50% optical shunt shielded. Data were analysed using Friedman’s test, Student t test and Pearson’s correlation coefficient (p < 0.05).ResultsIn dogs, SpO2 values were significantly higher at 1.0 cm than at baseline (p < 0.0001). In cats, there were no significant differences in SpO2 values at each location. There was no significant difference in SpO2 between 0% and 50% optical shunt in dogs. SpO2 had a moderate negative correlation with tongue thickness and negligible correlation with intersection angle.Conclusions and Clinical relevanceCirculatory anastomoses are probably responsible for observed changes in SpO2 as the probe is placed towards an extremity, rather than optical shunting or probe parallelity.  相似文献   

13.
1. Plumage loss was assessed by visual scoring in 288, 78‐week‐old hens, housed as groups of four in battery cages, which differed in the design of the cage front and the position of the nipple drinkers.

2. Half the hens had undergone beak trimming at 18 weeks, but in many cases regrowth had occurred.

3. Plumage damage and loss was significantly reduced in beak‐trimmed birds compared with birds with normal beaks. Tier and cage design had no effect.

4. This finding supports the idea that feather pecking is the important factor in causing plumage damage, rather than abrasion.

5. A comparison between 64 birds in which beak regrowth had occurred, and 64 in which it remained truncated, showed that both groups had similar plumage scores.

6. It appears to be the beak‐trimming procedure which is important; subsequent regrowth being irrelevant.  相似文献   


14.
The susceptibility of sheep to scrapie is modulated by the prion protein (PrP) genotype of the animal. An ambitious voluntary scrapie control programme was started in the Netherlands in 1998, based on selection of rams with theARR/ARR genotype for breeding. This programme was followed by an obligatory programme in 2004; the programme has been voluntary since 2007. We monitored the prevalence of PrP genotype frequencies and the prevalence of scrapie in the Dutch sheep population between 2002 and June 2010. Results showed that selection for scrapie-resistant sheep resulted in an increase in the ARR allele frequency in the Dutch national flock from 37.5% in 2005 to 61.4% in 2009. Moreover, surveillance data showed that there was a significant decrease in the prevalence of scrapie a few years after the start of the obligatory breeding programme, from more than 0.2% in 2004 to 0.015% in 2009. This decrease is a consequence of the increased number of scrapie-resistant sheep in the Dutch sheep population. To date, the results and the models based on the data show that the selective breeding programme should be continued for several years in order to successfully eradicate scrapie. It will be important to monitor the PrP frequency and scrapie prevalence in the Dutch sheep population in the coming years.  相似文献   

15.
Emerging Bartonella spp. infection can result in clinical symptoms such as endocarditis in humans and animals. This study analyzed the genetic phylogeny of the Bartonella spp. circulating in Iranian dogs. Also, this is first study on the relationship of Bartonella spp. and haematological factors from dogs in Fars. Ninety-eight blood samples were collected from the dogs of Fars province, Iran. Two different PCRs targeting rpoB gene and ITS sequence of Bartonella spp., followed by sequencing were performed. In addition, CBC and the differential count of WBC were determined. The “prevalence” of Bartonella spp. was 12.2 % (95 % CI: 5.72–18.68 %) in this population and the sequences matched with a newly proposed species; ‘Candidatus Bartonella merieuxii’. A significant increase in WBC due to neutrophilia and decreased RBC, Hct, and Hb concentrations were detected in Bartonella spp. infected dogs. The close contact between humans and dogs, and the zoonosis potential of Candidatus Bartonella merieuxii, emphasize on the need for more studies on ‘Candidatus Bartonella merieuxii’.  相似文献   

16.
1. This study examined the effect of α-tocopherol (α-T), sweet chestnut wood extract (SCW) and their combination on oxidative stress in vivo and oxidative stability of meat in broilers given diets rich in PUFA.

2. A total of 60 male broilers were individually caged and divided into 6 groups of 10. The C-PALM group received a diet with 7·5% palm fat and the other 5 groups with 7·5% linseed oil. The linseed oil groups were either un-supplemented (C-LIN) or supplemented with α-T or/and SCW as follows: αT-85 (C-LIN diet?+?68?IU vit E as all-rac-α-T/kg), αT-200 (C-LIN diet?+?183?IU vit E as all-rac-α-T/kg), SCW (C-LIN diet?+?3?g SCW/kg) and αT-SCW (C-LIN diet?+?68?IU vit E as all-rac-α-T/kg?+?3?g SCW/kg). Different parameters of oxidative stress were measured.

3. Linseed oil induced DNA fragmentation and malondialdehyde (MDA) formation, while α-T reduced both parameters, and SCW reduced the DNA damage. A combination (αT-SCW) also reduced plasma MDA. Larger antioxidant capacity of lipid soluble compounds were recorded in groups αT-85, αT-200 and αT-SCW than in the controls but there were no differences between these groups in antioxidant enzymes and total antioxidant status. A combination (αT-SCW) increased tocopherol concentrations in breast muscle and in comparison to the C-LIN group MDA concentrations were reduced in groups αT-85, αT-200 and αT-SCW.

4. It can be concluded that neither of the α-T concentrations were able to prevent all the negative effects of lipid oxidation in vivo and only high concentrations of α-T improved the stability of meat. With the exception of DNA damage, SCW had no impact on in vivo and in vitro measured markers of oxidative stress but may have a sparing or regenerating effect on α-T.  相似文献   

17.
Taxol has been used effectively in cancer therapies. Our previous study demonstrated that taxol induced altered maturation and improved viability of dendritic cells (DCs). However, the effects of taxol on DC viability have not been fully elucidated. In the present study, flow cytometric analyses revealed that taxol treatment significantly increased the number of viable DCs and the expression levels of a representative anti-apoptotic protein Bcl-xL. Furthermore, mobilization of the p65 subunit of nuclear factor-κB (NF-κB) from the cytosol to the nucleus in DCs was observed by confocal microscopy. An inhibition assay using N-p-tosyl-L-phenylalanine chloromethyl ketone confirmed that NF-κB was intimately involved in the effects of taxol on DC viability. In addition, we investigated the mechanisms of taxol enhancement of DC viability. Since taxol is a popular anticancer agent used in clinic, this study may provide a rationale for the use of taxol in DC immunotherapy to treat cancer patients. Taken together, these results confirm that taxol increases DC viability, and this information may provide new insights for new clinical applications of both taxol and DCs.  相似文献   

18.
Biosecurity compliance is generally poor in all types of animal production systems around the world. Therefore, it is essential to define strategies to improve the implementation of biosecurity measures. This study evaluated the value of audits and visible cameras on compliance with biosecurity measures required when entering and exiting poultry barns on 24 poultry farms in Québec, Canada. Short term (first two weeks) and medium term (six months later) compliance were determined. Application of biosecurity measures was evaluated using hidden cameras. Video viewing revealed a total of 2748 visits by 259 different individuals. Results showed that bimonthly audits did not have any impact on medium term compliance. Visible cameras had a significant impact on changing boots (OR=9.6; 1.9-48.4) and respecting areas (contaminated vs. clean) during the visit (OR=14.5; 1.2-175.1) for the short term period. However, six months later, compliance declined and was no longer significantly different from controls. Duration and moment of the visit, presence of the grower or an observer, barn entrance design, number of barns, number of biosecurity measures requested, type of boots worn, gender and being a member of a grower's family were significantly associated with biosecurity compliance.  相似文献   

19.
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20.
The effect of moderate-to-deep pressure on soft tissue has been studied in both humans and nonhuman animals with positive results shown in reducing anxiety and promoting relaxation. Canine anxiety disorders are often treated with medications and behavior modification programming. Pressure wraps are sometimes used to treat canine anxiety, but the effects of this investigation have not been rigorously investigated. The aims of this study were to investigate the use of a pressure wrap (ThunderShirt®; ThunderWorks, Durham, NC) on heart rate and behavior in dogs diagnosed with an anxiety disorder. Subjects were 90 dogs (39 males and 51 females) that were diagnosed with Separation Anxiety or Generalized Anxiety Disorder. Dogs were randomly assigned to 1 of the 3 groups, namely Experimental Group 1 (dogs wore the ThunderShirt® per manufacturer's recommendations), Experimental Group 2 (dogs wore the ThunderShirt® loosely without pressure), and Control Group (dogs had no specific treatment). Average and maximum heart rates were measured at baseline and after 15 minutes alone in the kennel. Dogs were video-recorded and analysis completed for 12 behaviors, namely pacing, panting, yawning, tongue-flicking, drooling, elimination, barking, stress whining, howling, licking, door orientation, and calmness. The results were as follows: Dogs in Experimental Group 1 showed significantly less increase from baseline in average heart rate than the Control Group dogs (P < 0.001) and dogs in Experimental Group 2 (P < 0.001). Dogs in Experimental Group 1did not differ significantly from Control Group dogs in maximum heart rate when all dogs were considered, but did differ significantly from the Control Group (P = 0.04) when only those dogs not currently on anxiety medication were considered. There were no statistically significant differences among groups on behavioral outcomes, except that the dogs in the Control Group were significantly more likely to orient toward the door than the dogs in both Experimental Groups 1 (OR = 7.46, P = 0.01) and 2 (OR = 4.42, P = 0.04). Dogs in the Experimental Group 1 presented a trend of less tongue-flicking (P = 0.06) and yawning (P = 0.07) stress reduction behaviors when compared with the other 2 groups. More research should be conducted with the ThunderShirt® on behavioral outcomes. The ThunderShirt® can be used with behavior modification programming and medication as an adjunct treatment option to assist dogs diagnosed with anxiety disorder to reduce heart rate.  相似文献   

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