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1.
A method to estimate genetic parameters with a model that considers selected base animals as fixed was investigated. The model estimates genetic variance as a conditional variance based on the Mendelian sampling of gametes from the base parents. In a simulation study, 20 sires were selected and each was mated to 20 dams to create 400 animals for the next generation. Selection was for five generations, but only animals of Generations 4 and 5 were assumed to have performance records and known parents. Simulated values for additive genetic and residual variance were 10. Estimated genetic variance was 8.58 when base animals were assumed random and 6.03 when they were assumed fixed. Residual variance was overestimated in the latter case. When males of Generation 4 were not selected to have progeny, estimated genetic variance was 9.91. It was concluded that estimates for genetic parameters in a model with base animals assumed as fixed were not biased by selection of base animals, but a new bias was introduced if descendants of fixed base animals were selected. Estimation of genetic variance from dairy records of daughters of AI test bulls gave differences of up to 8% when the model removed bias from selected base animals.  相似文献   

2.
A series of 6 daylight observations was made each summer and again each winter over 2 years to map cattle distribution on a California foothill pasture. Sixty animals were used in the study with no animals appearing in &spigt; 1 observation series. During daylight hours, small herds of cows containing between 14 and 16 animals were scan-sampled and videotaped every 15 minutes. A global positioning system was used to record the position of the camera to aid in accurately locating individual animals. Animal locations and individual identifications were then entered into a geographic information system (GIS) by on-screen digitizing using color orthophotographs. Animal positions were determined to be within 5 m of their true location. Association software, ASSOC1, was used to analyze animal positions to determine cattle subgroups and herd units. This position-based grouping was compared with observation-based grouping by researchers. Direct observation also identified dominant herd members. Older animals, up to 16 years of age, were generally dominant over younger animals, and subgroups tended to be composed of animals of similar age. The size of naturally occurring subgroups was between 3 and 6 animals. Some animals exhibited independence in their actions and behaviors compared with subgroup members. ASSOC1 produced grouping results consistent with direct observations. However, accurate interpretation of the ASSOC1 results depended on direct observational data. ASSOC1 identified close association patterns in 3 of the observations that defined the dominant animals in the herd. Forage availability and thermoregulatory needs influenced the distance between associated subgroup members. Distance between animals decreased when animals sought shade in summer or shelter in winter. Computer analysis of spatial data from GPS collars may be able to determine the social structure and identify dominant animals in herd situations. Incorporating knowledge of cattle social behavior should improve management of cattle on the range.  相似文献   

3.
Gross and histopathologic evaluation of skeletal muscle was performed in 229 equids (217 horses, 8 ponies, 3 donkeys, and 1 mule) 1 year of age or older undergoing postmortem examination at Oregon State University in a 2.5-year period. Animals were evaluated for grossly evident muscle lesions, and muscle samples were fixed in formalin, processed routinely, and stained with hematoxylin and eosin (HE) and periodic acid-Schiff (PAS) for glycogen. Muscle lesions were detected in 149 animals (65%). Chronic myopathic change (excessive fiber size variation and internal nuclei) was evaluated in horses without polysaccharide storage myopathy and was the most common finding (36 animals; 15.7%). Chronic myopathic change was more common in older animals. Generalized muscle atrophy was present in 30 animals (13.1%). Myonecrosis was attributed to endotoxic injury (11 animals; 4.8%), bone fracture (8 animals; 3.5%), bacterial infection (5 animals; 2.2%), muscle rupture (3 animals; 1.3%), selenium deficiency (2 animals; 0.9%), and exertional rhabdomyolysis (1 horse; 0.4%); cause was not determined in 9 animals (3.9%). Intramyofiber protozoa were detected in 19 horses and ponies (8.3%). Denervation atrophy was detected in 14 animals (6.1%). Neoplasia involving muscle occurred in 3 animals (1.3%), injection site reactions were detected in 4 animals (1.7%), and focal lymphocytic infiltrates were found in 6 animals (2.6%). Other findings were ring fibers (2 horses; 0.9%), fiber splitting (2 horses; 0.9%), and fat infiltration (1 horse; 0.4%). Skeletal muscle lesions are common in equids examined at postmortem. Transverse sections stained with HE and PAS are invaluable when evaluating equine muscle.  相似文献   

4.
The objectives of this study were to compare the age distribution of animals persistently infected (PI) with bovine virus diarrhea virus (BVDV) in 12 herds with clinical BVD compared to ten herds without clinical BVD and to examine the incidence of PI calves born after the oldest PI animal. Blood samples from all animals were tested for bovine virus diarrhea virus and antibodies. In five herds, blood samples were obtained from calves born after the whole herd had been tested. All calves born by PI dams were also blood tested. In herds with clinical BVD the median age of PI animals was 248 days and in herds without clinical BVD the median age was 144 days. There was no significant difference between the age of PI animals in herds with clinical BVD compared to herds without clinical BVD (p = 0.48) suggesting similar epidemiology of the occurrences of PI animals in the two herd categories. Thereafter, all herds were used to study the incidence of PI animals. A total of 129 PI animals were found. In ten herds with 72 PI animals the age range of PI animals was more than six months. In these herds 26.3% of the PI animals were born within the first two months after birth of the oldest PI animal, no PI animals were born 2- less than 6 months, 52.7% were born 6- less than 14 months, 6.9% were born 14- less than 22 months and 13.9% (all born by PI dams) were born later than 22 months after the oldest PI animal.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
The precalen-ce of caseous lymphadenitis was surveyed in 36 goat herds in Northern Norway. In each herd, information concerning the occurrence of the disease was obtained from the farmer. Adult animals (1 year of age or older) in 35 herds were examined for superficial swellings, and serum samples were collected from most animals in the herds. The sera were examined for antibodies to Corynebacterium pseudotuber-culosis using the bacterial agglutination test (BAT) and the hemolysis inhibition test (HIT).Gaseous lymphadenitis was diagnosed with certainty in 19 herds. Information from the farmers indicated that the disease indeed oc-curred in these herds, and that the majority had been infected with the disease for many years. The herds had apparently become infected through contact with animals from infected herds. Clinical examina-tions were carried out in 18 of these herds and superficial swellings were found in 26 % of the examined animals. The prevalence of ani-mals with lesions varied from 11 to 40 % among the herds. Of the animals in these herds, 81 % were positive in BAT and 84 % in HIT. The prevalence of positive animals varied from 26 to 99 % in BAT and 28 to 99 % in HIT. The prevalence of seropositive animals was lowest in a herd in which animals were kept separately in stalls.Caseous lymphadenitis could not be diagnosed in 16 herds. In-formation from the farmers indicated that the disease indeed seemed to be absent in 14 of these herds. These 14 herds had no history of contact with animals from herds considered to be infected. However, in the remaining 2 herds, the farmers were somewhat uncertain about the occurrence of the disease. One of these 2 herds had a history of contact with infected herds through participation in a goat “breeding circle”. Only a few of the animals were, however, seropositive and all these had low antibody titres.In 1 newly established herd, a single animal showed a high posi-tive titre in BAT only. All the other animals were negative in both tests. This particular herd consisted of animals obtained both from herds with caseous lymphadenitis and from herds in which the disease was not considered to occur.  相似文献   

6.
The survivorship of animals persistently infected with bovine virus diarrhoea virus was studied in ten Danish dairy herds. The ages of 34 persistently infected animals were compared with the ages of non-persistently infected animals in the herds in a cross-sectional study in which the risk rate of removal of animals in the two groups within 1 year was estimated from an exponential probability function of the age. In a cohort study, the 34 persistently infected animals were followed from the date of the initial blood test and onwards and the risk rates of dying or being slaughtered due to unthriftiness or either of these events were calculated.

The attributable risk of leaving the herds within 1 year was 0.35 among persistently infected animals. The risk rate of dying or being slaughtered due to unthriftiness within 1 year was 0.28 and 0.31, respectively; the risk rate of either of these events was 0.5.  相似文献   


7.
A retrospective study on the results of urethrostomy in 28 small ruminants was made. Ten animals were euthanised during surgery. In the 18 remaining animals short-term results were good. Recurrence of symptoms occurred in 8 animals (45%). Five animals were operated a second time, leading to 4 recurrences. Two animals were operated a third time and remained free of symptoms.  相似文献   

8.
The purpose of this paper was to describe the clinical findings in four cattle with abscesses in the cervical vertebrae. In all of the animals there was generalized ataxia and normal behaviour, mentation and cranial nerve function. All animals had marked difficulty rising and had generalized ataxia. The most important haematological and biochemical findings were a mildly increased concentration of plasma protein in all animals and a markedly increased fibrinogen concentration in two animals. A sample of cerebrospinal fluid (CSF) was collected from three animals. The protein content was mildly increased in the CSF samples of two animals. Based on the clinical findings, a tentative diagnosis of central nervous system disease with localisation in the neck region was made in all of the animals. Due to a poor prognosis, all of the animals were slaughtered. Postmortem examination revealed abscesses in the region of C3 to C6, which had resulted in extramedullary compression of the spinal cord. The abscesses varied in diameter from 2 to 8 cm.  相似文献   

9.
Severe bilateral fibrosing pleuritis was diagnosed in 5 cats and 2 dogs with chronic chylothorax. All animals were dyspneic on initial examination and remained moderately to severely dyspneic after thoracentesis. Radiographic evidence of fibrosing pleuritis included rounded lung lobes and failure of the lungs to reexpand following effective pleural drainage. Fibrosing pleuritis was also suggested in several animals with radiographic evidence of pleural fluid, in which pleural fluid could not be retrieved. Macroscopically, the lung lobes of all animals were compressed and atelectatic to various degrees, and the pleura appeared to be diffusely thickened and roughened. In several animals, fibrous adhesions were found between the parietal and visceral pleura of some lobes. Lung lobes were markedly constricted and appeared as small, smooth, rounded hilar masses in 4 animals. Mild to moderate pulmonary edema was evident in 3 animals at necropsy. Six of the 7 animals died (2) or were euthanatized (4) within 72 hours after the diagnosis of fibrosing pleuritis. The fibrosing pleuritis developed in 1 animal with lymphoblastic lymphosarcoma and chylothorax after treatment via passive pleuroperitoneal drainage; this animal was euthanatized because of underlying neoplasia. One cat, in which decortication was performed and resulted in marked reexpansion of the lung lobes, died 4 hours after surgery with signs compatible with pulmonary edema. On the basis of our findings, we suggest that animals with chronic chylothorax are at risk to develop fibrosing pleuritis. Furthermore, animals with severe bilateral fibrosing pleuritis should be given extremely guarded prognoses.  相似文献   

10.
Peritonitis was induced In 12 dogs by creation of an avascular jejunal loop. After 24 hours, the avascular jejunal loop was removed, and purulent material was removed by aspiration. The abdominal incision in six experimental dogs was left open under a bandage, while the incision was closed in six control dogs. All six open abdomen, and four control, dogs survived the 8 days of the study. The number of bacteria in the peritoneal exudate in experimental animals was less than in control animals. At the end of the 8 day study, experimental animals were more active, had better appetites, and were less likely to have fever, vomition, diarrhea, and dehydration. Experimental animals weighed significantly less than control animals. There were no differences between groups with respect to biochemical and hematologic parameters. At necropsy, experimental animals had fewer adhesions and less peritoneal fluid accumulation than control animals. Complications of open peritoneal drainage included persistent fluid loss, weight loss, adhesions of abdominal viscera to the bandage, and contamination of the peritoneal cavity with cutaneous organisms.  相似文献   

11.
A retrospective cohort study was conducted to determine the risk of bovine tuberculosis (TB) among animals sold out from herds that were free to trade animals during the year 2005 according to their bovine TB testing history during the year 2005. The present study sample comprised of 338,960 animals, of which 124,360 animals were sold out from herds that were restricted from trading at some stage during 2005 (bovine TB 'exposed') and 214,600 animals that were sold from herds which did not have their trading status withdrawn in 2005 (bovine TB 'non-exposed'). The overall risk of a diagnosis of bovine TB during the two-year period after the animals were sold out was 0.69 per cent. The odds of bovine TB were 1.91 higher for animals sold out from bovine TB 'exposed' herds compared with animals sold out from bovine TB 'non-exposed' herds (OR 95 per cent CI: 1.76 to 2.07, P<0.0001). Ten per cent of animals identified during field surveillance with bovine TB did so less than two months after being sold out in 2005, and similarly, 10 per cent of the animals classified as bovine TB positive by finding a bovine TB lesion at slaughter did so within 25 days (or less) of being sold out in 2005.  相似文献   

12.
Pathologico-morphological changes in the digestive tract were investigated in fifty naturally infected common foxes (Vulpes vulpes crucigera). Nineteen animals were found to suffer from mild cachexia, 31 animals suffered from complete cachexia. Erosions were observed in the mucosa of oral cavities of 21 foxes. Traumatic injuries appeared in the teeth of 11 animals. One case of swollen and hyperaemic tongue was described; in three cases there occurred sialo-adenitis. A mild degree of inflammation was recorded in the gullet in three animals. Fifteen animals had empty stomachs, thirty-five animals had atypical food or foreign bodies in the stomach contents; simple hyperaemia was recorded 18 times, acute catarrhal gastritis 19 times and haemorrhagic gastritis was observed in two cases. Acute catarrhal enteritis was found in six cases, haemorrhagic enteritis in one case.  相似文献   

13.
食品动物源产超广谱β-内酰胺酶大肠杆菌的流行状况调查   总被引：1，自引：1，他引：0  
本研究旨在了解产超广谱β-内酰胺酶(ESBLs)大肠杆菌和CTX-M型耐药基因在食品动物的流行状况。对分离自养殖场的1273株大肠杆菌(健康动物源755株,患病动物源518株),采用双纸片协同试验筛选ESBLs阳性菌,并通过PCR法和基因测序鉴定阳性菌CTX-M型的基因型。1273株食品动物源大肠杆菌中筛选出产ESBLs阳性菌181株,阳性率为14.2%,其中患病动物阳性率比健康动物高,分别为19.9%和10.3%。151株(83.4%)产ESBLs大肠杆菌中检测到CTX-M型基因,占所有食品动物源大肠杆菌的11.8%,其中以CTX-M-9G为主,阳性率为79.5%(120/151),远高于CTX-M-1G的携带率25.8%(39/151),其中8株同时携带了CTX-M-1G和CTX-M-9G。产ESBLs的大肠杆菌在食品源动物中流行普遍,CTX-M是产ESBLs阳性菌中的主要流行基因型。  相似文献   

14.
The kidneys of 37 Japanese Black calves aged 2 to 65 months diagnosed with Claudin 16 (CL-16) defect by the DNA-based test were examined pathologically. The animals exhibited clinical symptoms such as growth impairment, renal failure, overgrowth of hooves, and anemia at a young age. There was no correlation between the time of onset and age. Kidney weights relative to body weight were similar to those in normal animals, but both kidney net weights and size were reduced due to atrophy in animals that showed severe renal dysfunction. Histopathological examination of the kidneys showed reduction in the number of glomeruli, compensatory hypertrophy of glomeruli and tubules, and glomerular and tubular atrophy accompanied by interstitial fibrosis and lymphocytic infiltration. Glomeruli were clearly less in number in the kidneys of CL-16-defective animals than those of normal animals even in the cases with mild lesions. A small number of immature glomeruli and tubules were also detected, suggesting that there were fewer nephrons developed at birth in CL-16-defective animals. It was suggested that a defect of the CL-16 gene is involved in the "abnormal development of nephrons". Immunohistopathological examination of the kidneys showed that the epithelium of thick ascending limb of Henle was stained with anti-CL-16 antibody in the control animals, but not in the affected animals, suggesting a defect of CL-16 in the epithelium of renal tubules in the affected animals.  相似文献   

15.
Store pigs with spontaneous outbreaks and experimental endotoxin shock were kept under observation in the context of coagulation analysis. Heparin was applied to some of the animals to disrupt the plasmatic coagulation system. The thrombocyte count in animals with endotoxin infusion declined by some 50 to 65 percent of the original level. No statistically secured difference was found to exist between heparinised animals, on the one hand, and non-heparinised, on the other. The aggregation and adhesion of thrombocytes in all shock animals was more pronounced than that in the controls. The fibrinogen levels were lowered in both the animals with spontaneous outbreaks and the experimental animals. Thrombocyte alteration was not found to have been dependent on activation of the plasmatic coagulation system. In endotoxin shock cases activation of plasmatic coagulation proteins was found to be preceded by rise in thrombocyte aggregation.  相似文献   

16.
Hege  Kippenes  DVM  Patrick R.  Gavin  DVM  PhD  Ronald D.  Sande  DVM  MS  PhD  Dennis  Rogers  RT  Vaughn  Sweet  MS 《Veterinary radiology & ultrasound》2000,41(4):371-376
The purpose of this retrospective study was to evaluate the repositioning accuracy of different positioning devices in order to determine their applicability for potential use in conformal radiation therapy for animals. Forty-four animals with spontaneous tumors of the head were included. The animals were divided into 3 groups determined according to the positioning device used. Group 1 animals were positioned using a thermoplastic mask. Group 2 animals were positioned using a head holder. Group 3 animals were positioned using the head holder and an inflatable pillow. The time of presentation determined which position device was used. Port films of the 44 patients were reviewed retrospectively, and the repositioning precision was recorded by measurements in three orthogonal planes. Groups 2 and 3 had significantly better repositioning accuracy (P < or = 0.05) compared to Group 1. The position variation was not significantly different (P < or = 0.05) between Groups 2 and 3 in the lateral and longitudinal direction. Group 3 had a median reposition variation of 0.5 to 1.0 mm, with a standard deviation of 1.0 to 1.5 mm.  相似文献   

17.
A serological survey for bovine viral diarrhoea virus (BVDV) antibodies on a collection of 1295 serum samples obtained from 6-12 months old cattle originating from 45 farms in Slovakia was carried out. On 13 farms more than 90% of the examined animals were seropositive, on 14 farms 71-90% seroprevalence was observed, on 13 farms only 50-70% animals were found to be positive for BVDV antibodies, while the remaining 5 farms showed fewer than 50% seropositive animals. The average incidence of BVDV antibodies (around 70%) was similar as determined 30 years ago. Of 84 serum samples from seronegative animals originating from 14 farms in which 70-98% seropositivity was observed, six were positive in Ag-BVDV ELISA indicating persistently infected (PI) cattle. On a farm to which animals were imported from abroad, a BVD outbreak was observed. Of 110 animals tested, four were positive in Ag-ELISA indicating the presence of PI cattle on this farm. Genetic typing of two isolates from imported animals performed by RT-PCR (324/326 primers from 5'-UTR), sequencing of PCR products and computer-assisted phylogenetic analysis revealed that they belong to BVDV-1 h group.  相似文献   

18.
Companion animals owned by human patients with cryptosporidiosis (cases) and those animals owned by the wider human population (controls), were studied to determine whether Cryptosporidium was more likely to be excreted by case animals than controls. A total of 280 recently voided faecal samples (114 case animals and 166 control animals) were collected and tested by immunomagnetic separation and immunofluorescent microscopy. A multivariable model was also created to identify pet characteristics, contacts and management factors associated with Cryptosporidium infection in animals, using information collected by a standardized questionnaire. The model was designed to take into account the clustering of samples at the owner level and whether the sampled animal was a case or control.  相似文献   

19.
This paper describes the clinical findings and treatment of 67 sheep and goats with listeriosis. In 55 of them the diagnosis was made on the basis of the typical signs, which included vestibular ataxia, circling, head tilt and unilateral cranial nerve deficits, but in 12 animals a definitive diagnosis was made only after postmortem examination. The most significant haematological and biochemical findings were a high haematocrit in 16 animals, a high concentration of total protein in 33, a high concentration of bilirubin in 39 and a high concentration of urea nitrogen in 28 animals. Twenty-eight of the animals had a metabolic acidosis. Thirty-nine animals were treated with antibiotics, intravenous sodium chloride and glucose solutions and sodium bicarbonate. Ten of them survived and the others were euthanased because their condition deteriorated. Of the 10 that survived, nine were able to stand when they were first examined and one was in lateral recumbency. Of 15 animals treated with chloramphenicol, one survived; of 11 animals treated with oxytetracycline, two survived; and of nine animals treated with gentamicin and ampicillin, six survived.  相似文献   

20.
To investigate whether difference in SSRs distribution of 7 domestic animals genomes, the microsatellite sequence were searched by using MSDB (Microsatellite Search and Building Database) and analyzed in pig, horse, cow, goat, sheep, chicken and dog genomes.Preliminary results showed that SRRs number, frequency and density were found to be largely variable among these animals.The most abundant distribution was observed in dog genome with 1 436 242 identified SSRs loci.The minimum SSRs (276 564) number was found in chicken genome.Yet, the minimum SSRs (430 760) frequency and density were found in horse genome.Among these SSRs, mononucleotide repeat type motif was the most abundant and pentanucleotide repeat type motif was the rarest in all animals.Meanwhile, all the dominant SSRs for different repeat types were abundant in nucleotide A and T.In addition, there was variability among 7 animals of SSRs distribution.In general, SSRs distribution was the most similar in cow, goat and sheep genomes, and chicken was the most different from other animals.The results also showed that the length of microsatellite ranged mainly from 12 to 20 bp in all animals, which might be due to selection pressure of convergence.In short, these results revealed difference as well as conservation in SSRs distribution among different domestic animals genomes.In particular, genetically close animals tended to have similar SSR distribution patters.This would provide a basis for subsequent research of SSRs function.  相似文献   

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