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1.
Blood samples of 126 mature cows with “persistent” hematological status from two leukosis herds and a leukosis free control herd were collected for determining hematological status and estimation of replicating lymphocytes. To quantitate the number of DNA synthesizing cells, the blood was incubated with tritiated thymidine in vitro followed by autoradiography. Classification of animals according to lymphocytosis status did not reveal clearly whether or not a difference existed between the two leukosis herds. The estimation of DNA synthesizing lymphocyte counts showed that the animals from the two leukosis herds did not differ from each other while differing significantly from control herd animals. The study suggests that the similarities between the two leukosis herds, while ambiguous on lymphocyte counts alone, become clear when DNA synthesizing cell counts are compared. Thus the animals of the two leukosis herds belonged to the same “leukosis” population.  相似文献   

2.
A total of 763 fecal or intestinal samples from diarrheic calves and piglets were examined for viral content by immunofluorescence, electron microscopy or cell culture. Routine fluorescent antibody and cultural tests detected rotavirus (n=126), coronavirus (n=80) and bovine viral diarrhea virus (n=13). Electron microscopy detected rotaviruses (n=24) and coronaviruses (n=17) not identified by standard fluorescent antibody tests. Other viruses detected by electron microscopy included Breda virus-like particles (n=49), astroviruses (n=1), caliciviruses (n=1), rhabdoviruses (n=1), parvoviruses (n=2), enteroviruses (n=3), togavirus-like particles (n=2), and “chained” particles (n=5). Mixtures of several of the viruses were detected in a number of fecal samples.

The survey emphasized the value of electron microscopy as a broad-spectrum diagnostic tool.

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3.
Flight and avoidance reactions from human were examined using 168 postweaning Thoroughbred foals in 22 breeding farms. Further 114 yearlings of 168 foals were tested in the following summer. The foal handlings by the stabler were asked in questionnaire. The relationship between the behavioural reactions and the foal handling frequencies was analyzed. The flight reaction was estimated as the distance from the animal to a stranger when the animal began to flight away from his approach. The avoidance scores were set up from (1) (not resistant) to (5) (touch rejection) from human touching. In the stabler questionnaire, handling frequencies of “body brushing”, “rectal temperature measurement”, “hoof cleaning”, and “stall cleaning” in the early nursing period were asked. The handling frequencies were scored from (1) (not done) to (5) (every day). In the preliminary test, a measurement reliability of the flight distance and the avoidance score was confirmed. The mean flight distances were 0.56 m and 0.27 m in the postweaning foals and the yearlings, respectively. Touch-avoidance scores of the highest frequency were (3) and (2) in the postweaning foals and the yearlings, respectively. As the results of Spearman’s rank-correlation analysis, “body brushing” showed highly negative relationships with “flight distance” (ρ=–0.31, P<0.001) and “avoidance score” (ρ=–0.37, P<0.001) in the postweaning foals. In the yearlings, “hoof cleaning” also showed significantly negative relationships with these behavioural indices (ρ=–0.24, P<0.01; ρ=–0.22, P<0.01, respectively).  相似文献   

4.
In mice, one of the major epigenetic errors associated with somatic cell nuclear transfer (SCNT) is ectopic expression of Xist during the preimplantation period in both sexes. We found that this aberrant Xist expression could be impeded by deletion of Xist from the putative active X chromosome in donor cells. In male clones, it was also found that prior injection of Xist-specific siRNA could significantly improve the postimplantation development of cloned embryos as a result of a significant repression of Xist at the morula stage. In this study, we examined whether the same knockdown strategy could work as well in female SCNT-derived embryos. Embryos were reconstructed with cumulus cell nuclei and injected with Xist-specific siRNA at 6–7 h after oocyte activation. RNA FISH analysis revealed that siRNA treatment successfully repressed Xist RNA at the morula stage, as shown by the significant decrease in the number of cloud-type Xist signals in the blastomere nuclei. However, blastomeres with different sizes (from “pinpoint” to “cloud”) and numbers of Xist RNA signals remained within single embryos. After implantation, the dysregulated Xist expression was normalized autonomously, as in male clones, to a state of monoallelic expression in both embryonic and extraembryonic tissues. However, at term there was no significant improvement in the survival of the siRNA-injected cloned embryos. Thus, siRNA injection was largely effective in repressing the Xist overexpression in female cloned embryos but failed to rescue them, probably because of an inability to mimic consistent monoallelic Xist expression in these embryos. This could only be achieved in female embryos by applying a gene knockout strategy rather than an siRNA approach.  相似文献   

5.
Six adult dairy cows clinically diagnosed as hemorrhagic bowel syndrome (HBS) were the subjects of this study. The involved intestinal lesions were fixed in formalin and examined macroscopically and histopathologically. Pathological examinations revealed large intramural hematomas with necrotic foci, resulting in luminal obstruction. The mucosal layer in the lesions was detached from the intestinal wall, and there were no hemorrhagic changes in the lumen. The intramural hematomas were sometimes covered with histologically intact mucosal layer. These pathological findings were not consistent with those of “intraluminal blood clots” reported previously. Gram-positive and anti-Clostridium antibody-positive short bacilli were found in hemorrhagic necrotic areas. However, the exact relationship between Clostridium spp. observed in the lesions and HBS remains unclear, because this bacterium is a normal inhabitant in cattle.  相似文献   

6.
We investigated changes in the predicted functions of the rumen bacterial community in Japanese Black beef cattle during fattening. Nine cattle were fed a high-concentrate diet during the early, middle, and late fattening stages consecutively (10–14, 15–22, and 23–30 months of age, respectively). The rumen fluid and solid samples collected at each stage were subjected to sequencing analyses. The sequencing results were clustered and classified into operational taxonomic units (OTUs). Representative sequences and a raw counting table for each OTU were submitted to the Piphillin website. The predicted functions were revealed by the Kyoto Encyclopedia of Genes and Genomes database as the ratio of the total sequence. In the early stage, “Biosynthesis of secondary metabolites” was significantly higher in the fluid fraction than in the solid fraction. “Two-component system” in the middle stage was significantly lower and “Purine metabolism” in the late stage was significantly higher in the fluid fraction than those in the solid fraction. The fluid fraction was significantly correlated with acetic acid, propionic acid, and bacterial metabolism, such as “Biosynthesis of secondary metabolites” and “Sugar metabolism.” Moreover, the solid fraction was correlated with “Purine metabolism” and “Biosynthesis of secondary metabolism”. These results suggest that the rumen bacterial community in Japanese Black beef cattle adapts to changes in rumen conditions by altering their functions in response to a long-term high-grain diet.  相似文献   

7.
8.
Determination of the seleno-enzyme glutathione peroxidase (GSH-Px) in blood from Danish Landrace pigs was done using a quantitative, spectrophotometric method and a simple “spot test”. A close correlation between the net reaction rate measured spectrophotometrically (Δ A/min.) and time for defluores-cence (minutes) was obtained (r2 = 0.72—0.77, P < 0.0005). From these results the factors used for a conversion of defluorescence time to u/g hemoglobin were evaluated. The results further showed that the “spot test” can be used as a screening method for detection of subnormal GSH-Px levels in pigs.While red cell GSH-Px seems independent of the sex, an elevation of both plasma and red cell GSH-Px was found with increasing age of pigs. The normal range of red cell GSH-Px activity was wide, contrasting the small variations observed in the individual pig. Some evidence that porcine red cell GSH-Px is under genetical control was found and discussed in relation to the possible use of GSH-Px as an indicator of the pig''s selenium status.  相似文献   

9.
This study evaluated whether acepromazine or methadone reduced behavioral parameters, overall excitement, and activity associated with midazolam administration to healthy dogs. Dogs received midazolam (M) alone [M: 0.25 mg/kg body weight (BW)] or with methadone (MM) (MM: 0.75 mg/kg BW) or acepromazine (MA) (MA: 0.03 mg/kg BW) or saline (S) solution alone, all intramuscularly. Two blinded observers evaluated behavioral parameters using video recordings 30 min before and after injection of drugs. Accelerometery was used to evaluate “total activity counts” (TAC) at baseline and post-treatment. Post-treatment excitement scores were significantly higher in M and MA compared to baseline, M and MM compared to S, and M compared to MA. Behavioral parameters showed significantly higher proportions of “pacing” post-treatment in all groups receiving midazolam, and “restlessness,” “chewing/licking,” and “sniffing” in M. No significant differences were found for TAC at baseline and post-treatment. Midazolam-induced paradoxical behavioral changes (excitation, panting, pacing, restlessness, licking/chewing, and vocalization) were not prevented by acepromazine or methadone in healthy dogs.  相似文献   

10.
Biopsies of skeletal muscle collected from 24 animals classified as “double muscled” were examined by light and electron microscopy. The muscle samples exhibited degenerative changes including the presence of vacuolations and lamellated structures, fragmentation of myofibers, accumulation of glycogen granules, disruption of neuromuscular junctions and disorganization of the sarcolemma. In the light of the excessive fragility of the erythrocyte membranes noted previously, the alteration in the sarcolemma suggests that a generalized cell membrane defect may be the most consistent feature of the “double muscling syndrome” in cattle.  相似文献   

11.
Whereas in former times horses were reserved primarily for people involved in agriculture, elite equestrians or the military, nowadays equestrian sport has become an activity for people with a wide variety of backgrounds. However, as more and more people become involved with equestrian sport today, the knowledge concerning animal husbandry in general is diminishing due to an alienation from agricultural themes in modern societies. As a consequence, this development affects both riding ability and the appraisal of horses, especially with respect to the purchase of horses. In order to analyse which factors influence purchase decisions in the horse market in conjunction with equestrian experience, 739 horse riders were surveyed on their purchase behaviour in this study. Using cluster analysis, a typology was generated that provides a differentiated picture of the preferences of the various rider groups. Three clusters were distinguished: the “amateurs”, the “experienced” and the “experts”. Taking personal horse riding proficiency into account, it could be concluded that especially the “amateur” group required objective criteria for the evaluation of a horse they are considering purchasing. Alongside “measureable” qualities, such as previous showing success or the level of training of the horse, also other attributes such as the simple handling of the horse should be taken into consideration. As particularly the “amateur” group in equestrian sport is increasing in numbers, it is therefore advisable when preparing a horse for sale to align oneself to the needs of this customer segment in order to ensure an effective and targeted marketing of horses.  相似文献   

12.
Objective To characterize conjunctival lymphoid nodules obtained from the nictitans of healthy cats to determine if the follicle‐associated epithelium (FAE) of conjunctiva‐associated lymphoid tissue (CALT) in this species contains membranous (M)‐cells analogous to those described in other regions of mucosa‐associated lymphoid tissue (MALT). Methods Lymphoid follicles from nictitan bulbar surfaces of 10 healthy cats (20 eyes total) were examined. Nictitans from five cats were harvested immediately post‐mortem and a minimum of 12 lymphoid nodules from each third eyelid were isolated using a Zeiss operating microscope. At least three lymphoid follicles from each eye were examined using light microscopy (LM), transmission electron microscopy (TEM), and scanning electron microscopy (SEM) using standard fixation and embedding protocols. Nictitan‐lymphoid follicles from another five healthy cats were processed for immunohistochemistry to characterize the distribution of T‐ and B‐lymphocytes present beneath the FAE. Results The FAE overlying CALT from 10 healthy cats demonstrated morphology characteristic of M‐cells including attenuated apical cell surface with blunted microvilli and microfolds, invaginated basolateral membrane forming a cytoplasmic pocket, and diminished distance between the apical and pocket membrane. Immunohistochemistry of lymphoid tissue subtending the FAE demonstrated B‐cell dependent regions in the germinal centers surrounded by T‐cell dependent interfollicular zones. Conclusions Healthy feline CALT contains morphologic features analogous to those described in other regions of MALT. Documentation of feline conjunctival M‐cells is of clinical relevance in the study of primary infectious, allergic, and autoimmune ocular diseases, as well as a potential means of vaccination or drug delivery.  相似文献   

13.
Monocytes play an essential role in the defense against bacterial pathogens. Bone marrow (BM) and peripheral blood (PB) monocytes in pigs consist of the main “steady-state” subpopulations: CD14hi/CD163-/SLA-DR- and CD14low/CD163+/SLA-DR+. During inflammation, the subpopulation of “inflammatory” monocytes expressing very high levels of CD163, but lacking the SLA-DR molecule (being CD14low/CD163+/SLA-DR-) appears in the BM and PB and replaces the CD14low/CD163+/SLA-DR+ subpopulation. However, current knowledge of monocyte migration into inflamed tissues in pigs is limited. The aim of the present study was to evaluate the distribution of “inflammatory” CD14low/CD163+/SLA-DR- monocytes during experimental inflammation induced by Actinobacillus pleuropneumoniae (APP) and a possible role for chemokines in attracting “inflammatory” CD14low/CD163+/SLA-DR- monocytes into the tissues. Monocyte subpopulations were detected by flow cytometry. Chemokines and chemokine receptors were detected by RT-qPCR. The “steady-state” monocytes were found in the BM, PB, spleen and lungs of control pigs. After APP-infection, “inflammatory” monocytes replaced the “steady-state” subpopulation in BM, PB, spleen and moreover, they appeared in an unaffected area, demarcation zone and necrotic area of the lungs and in tracheobronchial lymph nodes. They did not appear in mesenteric lymph nodes. Levels of mRNA for various chemokines with their appropriate receptors were found to be elevated in BM (CCL3-CCR1/CCR5, CCL8-CCR2/CCR5, CCL19-CCR7), necrotic area of the lungs (CCL3-CCR1, CCL5-CCR1/CCR3, CCL11-CCR3, CCL22/CCR4) and tracheobronchial lymph nodes (CCL3-CCR1) and therefore they could play a role in attracting monocytes into inflamed tissues. In conclusion, “inflammatory” monocytes appear in different lymphoid tissues and the lungs after APP infection in pigs. Various chemokines could drive this process.  相似文献   

14.
Two nitrofuran feed additives, 0.011% nihydrazone and a combination of 0.0055% nitrofurazone and 0.0008% furazolidone, improved weight gains and feed conversions in chickens with “air sac infection.” Both nitrofurans caused a significant reduction in the total chickens condemned at the dressing plant from this disease, but nihydrazone gave the best results.

Nihydrazone*, a new nitrofuran feed additive for chickens, was found by Wolfgang et al. (1) to be effective against coccidiosis due to Eimeria tenella and E. necatrix. In chickens nihydrazone was shown by Edgar et al. (2) to result in fewer chickens condemned from “air sac infection” than with any other drug used. Rosenberg et al. (3) found nihydrazone caused significant reduction in condemnations due to this disease. Cosgrove (4) showed that nihydrazone prevented an outbreak of cecal coccidiosis, reduced the incidence of “air sac infection,” improved weight gains, feed conversions and livability. Bierer (5) found nihydrazone active against fowl typhoid.

Harwood et al. (6) reported bifuran** effective against E. tenella and E. necatrix coccidiosis and it has been used commercially for this purpose. Bierer (5) (7) found Bifuran*** active in prevention of pullorum disease and fowl typhoid in chicks.

The mode of action of nihydrazone and nitrofurazone against E. tenella coccidiosis was shown by Johnson and Van Ryzin (8).

This production efficiency study was undertaken to evaluate nihydrazone and bifuran in the presence of “air sac infection” and concomitant diseases under field conditions. Camden (9) states that the only satisfactory test of a drug is the performance it gives under field conditions.

Nihydrazone (1) (5) and Bifuran (5) (6) have both antibacterial and antiprotozoal activity and under field conditions, normal densities of bacterial and other parasitic organisms are encountered (9). Thus a coccidiostat having antibacterial and antiprotozoal properties is desirable (7).

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15.

Background

Pampas deer, Ozotoceros bezoarticus (Linnaeus 1758), is a South American grazing deer categorized as "near threatened". However, knowledge about pampas deer behavior including courtship and mating is scarce and incomplete. The aim of this study was to characterize the courtship and mating behavior of the pampas deer (Ozotoceros bezoarticus), an endangered species from South America.

Methods

We performed focal observations of 5 males allocated at the Estación de Cría de Fauna Autóctona Cerro Pan de Azúcar, Uruguay, 4 times a day from 5 to 20 minutes each time on a daily basis from February to May. During that period we recorded all courtship and mating behaviors, as well as quantified the frequency of the specific behaviors shown. As mating were rarely observed, we recorded that behavior when it was observed in the context of other studies performed in the same population during the following 2 years.

Results

During the observation period we recorded 928 courtships and 5 mating periods. In addition, we recorded 10 more matings performed during other studies, totaling 15. The duration of each mating calculated from the 15 recordings was 3.9 ± 0.4 s, and the total period of female receptivity (from first to last mating acceptance) was 8.2 ± 1.1 min. Main observed courtship behaviors in males were “chase” and “ostentation”, while the most observed close to mating were “chinning”, “raised head” and “anogenital sniffing”. The most observed behaviors in females during the mating period were “vulva exhibition” and “move away”.

Conclusion

This is the first detailed report in pampas deer mating behavior. Estrus lasted only 8 min accepting only 3 short copulations per estrus. However, female behavior during courtship can be characterized as highly proceptive.  相似文献   

16.
The effect of prolactin suppression during lactation was studied in 6 sows nursing 5–10 piglets. In order to inhibit prolactin secretion a dopamin agonist (bromocriptine, Parlodel® “Sandoz”) was given per os from about 4 weeks after parturition until weaning 9–17 days later. Plasma prolactin and plasma progesterone were determined by radioimmunoassays. In all animals plasma prolactin was suppressed during the bromocriptine treatment. Two sows resumed ovarian activity during treatment as indicated by elevated plasma progesterone, probably as a result of the low plasma prolactin levels. The results suggest that the elevated plasma prolactin levels during lactation is one of the factors responsible for lactational an oestrus in the sow.  相似文献   

17.

Background

Hereditary ataxias with similar phenotypes were reported in the Smooth-Haired Fox Terrier, the Jack Russell Terrier and the Parson Russell Terrier. However, segregation analyses showed differing inheritance modes in these breeds. Recently, molecular genetic studies on the Russell group of terriers found independent mutations in KCNJ10 and CAPN1, each associated with a specific clinical subtype of inherited ataxia. The aim of this study was to clarify whether or not Smooth-Haired Fox Terriers with hereditary ataxia and dogs of other related breeds harbor either of the same mutations. A sub goal was to update the results of KCNJ10 genotyping in Russell group terriers.

Findings

Three Smooth-Haired Fox Terriers with hereditary ataxia and two Toy Fox Terriers with a similar phenotype were all homozygous for the KCNJ10 mutation. The same mutation was also found in a heterozygous state in clinically unaffected Tenterfield Terriers (n = 5) and, in agreement with previous studies, in Jack Russell Terriers, Parson Russell Terriers, and Russell Terriers.

Conclusions

A KCNJ10 mutation, previously associated with an autosomal recessive spinocerebellar ataxia in Jack Russell Terriers, Parson Russell Terriers, and Russell Terriers segregates in at least three more breeds descended from British hunting terriers. Ataxic members of two of these breeds, the Smooth-Haired Fox Terrier and the Toy Fox Terrier, were homozygous for the mutation, strengthening the likelihood that this genetic defect is indeed the causative mutation for the disease known as “hereditary ataxia” in Fox Terriers and “spinocerebellar ataxia with myokymia, seizures or both” in the Russell group of terriers.  相似文献   

18.
Hyperostosis in Newborn Pigs   总被引:1,自引:1,他引:0       下载免费PDF全文
Hyperostosis “thick legs” is reported in a case involving 7 of a litter of 11 purebred Landrace piglets. The 12 limbs involved showed variable degrees of thickening and immobility; tension and fixation of the skin. Necropsy revealed extensive fibrous connective tissue, enlargement and edema of associated lymph nodes and hypoplasia of muscle groups. Radiographs revealed osteodystrophia along the shafts of long bones. The case is compared to previous reports of infantile cortical hyperostosis in children and “thick legs” in pigs.  相似文献   

19.
20.
Extraskeletal osteosarcoma is extremely rare in mice. This case report demonstrates a spontaneous murine extraskeletal osteosarcoma that exhibited various histological growth patterns in an ICR mouse. At necropsy, the tumor mass was located in the abdominal wall and was 45 × 30 × 25 mm in size. Histopathologically, the tumor showed the following four growth patterns: a solid pattern of polygonal cells embedded in an osteoid eosinophilic matrix with calcification, an irregular sheet pattern of short spindle cells accompanying some eosinophilic multinucleated cells, a fascicular pattern of spindle cells and a cystic pattern lined by short spindle cells. Immunohistochemically, most of the tumor cells were positive for vimentin, proliferating cell nuclear antigen and osterix. The multinucleated cells mentioned above were desmin positive and were regarded as regenerative striated muscles but not tumor cells. Since no clear continuity with normal bone tissues was observed, the tumor was diagnosed as an “extraskeletal osteosarcoma.”  相似文献   

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