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1.
The immune responsiveness of mice (without prior natural exposure) and mares (with naturally acquired antibodies) was determined following vaccination with Actinobacillus equuli outer membrane proteins (OMPs) and/or recombinant A. equuli toxin (rAqx). Mice were vaccinated subcutaneously on days 0 and 21 with one of three doses (5, 25 or 50μg) of A. equuli OMPs, rAqx or both, together with Freund's incomplete adjuvant (FIA). Antibodies against formalin-killed whole bacterial cells (WBCs), OMPs and Aqx were determined on days 0, 21 and 42. Mares were vaccinated subcutaneously on days 0 and 21 with 100μg OMPs, 100μg rAqx or a combination of 50μg of each antigen, together with FIA. Antibodies against WBCs, OMPs and Aqx were determined at 7day intervals for the first 42days, as well as on days 56, 70, 154 and 238. Vaccination of mice stimulated an apparent dose response to OMPs and Aqx. Antibodies against OMPs and Aqx were enhanced following vaccination of mares that had naturally acquired pre-existing antibodies. There was no evidence of interference with antibody responses to the individual antigens when OMPs and rAqx were combined prior to vaccination.  相似文献   

2.
Actinobacillus equuli is found in the normal oral flora of horses, but has been associated with several diseases, and particularly with the usually fatal septicaemia in neonatal foals which is thought to be associated with a failure of the passive transfer of immunoglobulins via the colostrum. The Aqx protein of A equuli, belonging to the RTX family of pore-forming toxins, is also cytotoxic to horse lymphocytes. The presence of antibodies to Aqx was investigated in sera from individual horses from different regions; the sera from adult horses and foals 24 hours after birth reacted with Aqx, and sera from foals sampled shortly after an intake of colostrum also reacted with Aqx, but sera from foals taken before an intake of colostrum did not react with Aqx.  相似文献   

3.
Oral swab samples, serum and colostrum was taken from 15 mares and 14 of their foals, within 24 h of birth. The presence of antibody against Actinobacillus spp. isolated from the oral cavity was investigated using agar gel immunodiffusion. Antibodies against 48 out of the 77 Actinobacillus isolates from all horses in the study were present in the respective sera of 13 mares and 9 foals. In 11 mother-foal pairs, the antibody content of the foal serum was similar to that of the mare, and in 9 cases this was reflected in the antibody content of colostrum from the mare. The results indicate that an immune response to Actinobacillus spp. colonising the oral cavity is present in many adult horses and that this immune response can be transferred from mother to foal via colostrum.  相似文献   

4.
Horses naturally exposed to West Nile Virus (WNV) or vaccinated against WNV develop humoral immunity thought to be protective against development of clinical disease in exposed or infected animals. No reports evaluate the efficacy of passive transfer of naturally acquired specific WNV humoral immunity from dam to foal. The purpose of this study was to investigate passive transfer of naturally acquired immunity to WNV to foals born in a herd of semi-feral ponies, not vaccinated against WNV, in an endemic area, with many dams having seroconverted because of natural exposure. Microwell serum neutralization titers against WNV were determined in all mares and foals. Serum IgG concentration was determined in foals by serial radial immunodiffusion. Differences in IgG concentration between seropositive and seronegative foals were examined by means of the Mann-Whitney U-test. Linear regression was used to evaluate the association between mare and foal titers. Seventeen mare-foal pairs were studied; 1 foal had inadequate IgG concentration. IgG concentration was not different between seronegative and seropositive foals (P = .24). Mare and foal titers were significantly correlated in foals with adequate passive transfer of immunity (Spearman's rho = .84; P < .001); >90% of the foal's titer was explained by the mare's titer (R2 = 0.91; P < .001). Passive transfer of specific immunity to WNV is present in pony foals with adequate passive transfer of immunity born to seroconverted mares.  相似文献   

5.
Six mares were treated on the day of parturition with an intramuscular injection of 0.2 mg kg-1 ivermectin and placed in a pasture free of equine parasites as soon as possible after foaling. The mares and their foals were compared with a similar group of untreated mares and foals on an adjoining pasture. The experimental data was derived from mare and foal fecal egg counts, foal necropsies and pasture larval counts. Ivermectin administered to mares on the day of parturition, when combined with movement to parasite-free pastures, significantly lowered the cyathostome (small strongyle) egg production for 4 months. This reduced cyathostome exposure was reflected in lower worm-burdens in their foals for 5 months. The results indicate that ivermectin will effectively control equine strongyles when mares and their foals are moved to parasite-free pastures.  相似文献   

6.
This paper describes the general management of mares and foals during the perinatal period and the methodology used in a collaborative research project on equine prematurity. Sixteen mares with dated pregnancies delivered 45 foals over three breeding seasons (1981 to 1983). In the majority, parturition was induced with oxytocin and/or fluprostenol; the remainder were allowed to foal spontaneously. Pre-colostral milk analysis provided a means of assessing the pre-foaling status of the mare. All were observed and monitored before, during and after parturition and the sampling protocol for both mare and newborn foal is discussed in detail. The foals were assessed for their degree of maturity at birth using behavioural, haematological, acid-base status and other criteria; they were then assigned to groups for further study and tests.  相似文献   

7.
Reasons for performing study: Stem cells derived from umbilical cord tissue (UCT) and umbilical cord blood (UCB) in human subjects and horses can be obtained in a minimally invasive fashion with successful propagation of mesenchymal stem cells (MSCs). Currently there are no detailed protocols documenting a procedure to harvest UCB and UCT safely for equine stem cell propagation. Hypothesis: UCB and UCT could be collected without harm to mare or foal. Objectives: To develop a standard and safe method for UCB and UCT collection, and prospectively to compare foal and mare health between groups of animals where tissue was and was not collected. Methods: This study was conducted at a Thoroughbred breeding facility in central California in 2008. UCB and UCT were collected from 40 mare and foal pairs. Clinical parameters including time for foal to stand and nurse, time for mare to pass the placenta, and foal haematology data at age 24 h were documented and compared to a control group, consisting of the succeeding 40 mare and foal pairs. Results: UCB was obtained successfully from 36 of 40 (90%) mares and UCT from 38 of 40 (95%) mares. Bacterial contamination was documented in 6 out of 36 (16.6%) UCB samples. There were no significant differences in time to stand or nurse for foals or time to pass the placenta for mares, between the experimental and control groups. There were no clinically relevant differences identified in haematological data obtained from foals with and without UCB collection. Conclusions: UCB and UCT can be harvested safely without harm to mares or foals. Potential relevance: UCB and UCT samples collected in an inherently contaminated environment can be successfully disinfected and transported with minimal bacterial overgrowth for use in cell culture to isolate MSCs.  相似文献   

8.
Cryptosporidium infection was molecularly investigated in mares and in their neonatal foals for which the occurrence of foal heat diarrhoea was also assessed. Thirty-seven mare/foal pairs were included in the study. All foals were born in the same stud farm during 2006-2008 breeding seasons. Two faecal samples, one prior to and one after delivery were collected from each mare, whereas three faecal samples were taken from each foal, i.e. at 8, 10 and 12 days of age. All samples (74 from mares and 111 from foals) were divided into two aliquots, one of which was examined for the presence of Cryptosporidium by a commercially available microplate ELISA kit, while the second aliquot of all ELISA-positive samples was molecularly examined. Nine out of 37 examined foals presented foal heat diarrhoea and one of them scored positive for Cryptosporidium, together with its mare. More specifically, four samples belonging to the same mare/foal pair resulted positive for Cryptosporidium upon both ELISA and PCR. The sequence analysis of the COWP gene showed the occurrence of the zoonotic species Cryptosporidium parvum. The possibility that foal heat diarrhoea-like episodes may be due to neonatal cryptosporidiosis and their relevance for the health of horses and of humans handling diarrhoeic neonatal foals and their mares are discussed.  相似文献   

9.
Serum samples of 20 horses were evaluated for antibodies against RBC after homologous blood transfusion. Transfusion-associated antibodies against RBC were detected in 10 horses. Antibodies recognizing horse blood group antigens Aa, Ae, Db, and Dc were identified. Antibodies against Aa were found in all samples from Aa-negative horses that were transfused with Aa-positive RBC. Antibodies against Aa persisted for at least 1 year after transfusion. Antibodies against Ae were detected in 7 of 8 horses transfused with Ae-positive RBC. Initial appearance and persistence of antibodies against Ae differed among the horses; antibodies were initially detected 1 week to 154 weeks after transfusion and disappeared as early as 4 weeks after transfusion. Antibodies against Db or Dc were detected in less than or equal to 33% of the horses that lacked Db or Dc antigens and were transfused with Db- or Dc-positive RBC. Antibodies against Db and Dc were initially detected in sera later than were the A-system antibodies. Three mares with transfusion-associated antibodies subsequently produced healthy offspring. Two foals had RBC antigens corresponding to their dam's alloantibodies; maternal colostrum with antibodies against Aa was withheld from the Aa-positive foal. The Db-positive foal remained healthy after nursing the mare with serum antibodies against Db.  相似文献   

10.
Clostridium difficile infection can occur in the dams of sick foals, but it is unknown if mares and foals share the same isolates. In this study, C. difficile isolates from fecal samples of 11 mares paired with 11 foals were genotyped by arbitrarily primed PCR; two mares and three foals in five mare-foal pairs had diarrhea. Fecal immunoassays were utilized to detect C. difficile common antigen and toxin A. Quantitative real-time PCR (qPCR) systems were developed to detect genes for toxins A and B, as well as for binary toxin B. Sequences of all toxins were present in all isolates, although only one horse was positive for toxin A on fecal immunoassay. Identical strains of C. difficile were present in 4/11 (36.4%) mare-foal pairs. Mare-foal pairs can harbor C. difficile subclinically and are potential reservoirs for colonization of each other.  相似文献   

11.
The purpose of this study was to investigate the changes in serum concentrations of prolactin (PRL), progestagens, and estradiol-17β and biochemical parameters during peripartum in an agalactic mare, as well as to study the periparturient indices of the foal. A 4-year-old Thoroughbred, primiparous, pregnant mare was diagnosed as agalactic from clinical conditions such as absence of observable udder development and weight loss of her foal after parturition. Serum PRL concentrations of the agalactic mare during prepartum tended to be lower than those of the control mares (19.5 ng/mL and 67.0 ± 15.0 ng/mL on the day of parturition, respectively). The progestagens and estradiol-17β concentrations were not markedly different between the agalactic mare and the control mares. Concentrations of γ-glutamyl transferase of the agalactic mare were higher than those of the control mares (P < .05). Although the serum immunoglobulin G concentrations of the foal of the agalactic mare after 24 hours of age were lower than those of the foals of the control mares (P < .05), all periparturient indices regarding the agalactic mare were considered to be within the normal range. In contrast, insufficient udder development and milk production was observed in the agalactic mare through the pre- and postpartum periods. We have ruled out the known causes for agalactia in mares based on other parameters, clinical symptoms, and nutritional causes. Clinical symptoms and PRL parameters in this case report are consistent with the category of agalactia in mares of unexplained causes, and we have determined additional blood parameters associated with agalactia in mares that are consistent with this category.  相似文献   

12.
The records of 361 Standardbred mares and their 1986 or 1987 foals were evaluated to identify factors associated with failure of passive transfer (FPT) of colostral antibodies in equine neonates. Sixty-five foals (18%) were classified as FPT based on a serum immunoglobulin concentration of less than 400 mg/dl at 24 to 36 hours of age, determined by the glutaraldehyde coagulation test. The potential association of mare- and foal-related factors with FPT were assessed by reviewing a series of multiple logistic regression models. The season in which the mare foaled and foal exam score, a subjective assessment of foal vigor, maturity, and general health, were the primary factors associated with the development of FPT. Foals with FPT were more likely (odds ratio = 3.50; 95% confidence interval = 1.81-6.68) than normal foals to require medical therapy during the first 3 months after parturition.  相似文献   

13.
Detomidine was administered throughout 10 pregnancies in eight mares. An intravenous injection of 20 micrograms/kg body weight was given weekly from Day 14 to Day 60 of gestation and thereafter every four weeks until parturition. One mare suffered torsion of the large colon and was destroyed on Day 86; the foetus was normally developed. A further mare aborted at 167 days. The remaining eight pregnancies continued to full term. One foal was delivered by caesarean section because of torticollis and, of the seven foals born spontaneously, one had bilateral upward patellar fixation at one month old. Therefore, although only six of the 10 foals developed normally, the other four cases showed no pathological similarities to suggest a common cause. Although these data were based on a small number of mares, they did not suggest that the repeated administration of detomidine had specific adverse effects on the pregnancies.  相似文献   

14.
REASONS FOR PERFORMING STUDY: Anecdotal speculation suggests that prognosis for survival of mares and foals following correction of uterine torsion has improved over the past 30 years. OBJECTIVES: To determine statistically the outcome of uterine torsion according to duration of clinical signs, stage of gestation, parity, physical examination findings, method of correction, prognosis for survival and reproductive health of the mare, and prospects for the foal within the neonatal period. METHODS: This retrospective study combined cases from 4 equine referral hospitals. RESULTS: The stage of gestation at which uterine torsion occurred was a risk factor for survival of mare and foal. Overall mare survival was 53/63 (84%); when uterine torsion occurred at < 320 days gestation, 36/37 (97%) of mares survived compared to 17/26 (65%) survival rate when uterine torsion occurred at > or = 320 days gestation. Overall foal survival was 54% (29/54). When uterine torsion occurred at < 320 days gestation, 21/29 (72%) foals survived compared to 8/25 (32%) when uterine torsion occurred at > or = 320 days gestation. Thirty mares were discharged from the hospital carrying a viable fetus following uterine torsion correction and 25/30 (83%) of these mares delivered live foals that survived beyond the neonatal period. CONCLUSIONS: Prognosis for survival for mares and foals following uterine torsion is good and improves if torsion occurs < 320 days compared to > or = 320 days gestation. CLINICAL RELEVANCE: Gestational timing of uterine torsion should be considered when advising clients about the prognosis for survival of the mare and foal. The prognosis for a mare delivering a live foal is good if the mare is discharged from the hospital following uterine torsion correction with a viable fetus.  相似文献   

15.
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16.
Postpartum, presuckle, colostrum samples were collected from 100 mares. Colostral specific gravities significantly correlated (r = 0.9) with colostral immunoglobulin (Ig)G concentrations. Foal serum IgG concentrations highly correlated (r = 0.82) with specific gravities of the colostrum each foal ingested. Eight of 48 foals (17%) had serum IgG concentrations less than 400 mg/dl. The dams of these 8 foals had colostral sp gr less than 1.06 and colostral IgG concentrations less than 3,000 mg/dl. Foals had serum IgG concentrations greater than 520 mg/dl 24 hours after parturition, when the colostral specific gravity of the dam was greater than or equal to 1.06. Effects of breed on colostral specific gravity, colostral IgG concentrations, foal serum IgG concentrations, and mare serum IgG concentrations were not significant.  相似文献   

17.
The aim of the present study was to evaluate the clinical applications and limitations of daily low-dose oxytocin injections for the induction of parturition in pregnant at term mares, the attention was focussed on the efficacy of the treatment and on its possible negative effects on mare and foal. Three-hundred and fifty pregnant full term Standardbred mares were used: 176 were allowed to foal spontaneously, 174 were treated daily with 3.5 IU of oxytocin i.m. when mammary secretion showed a calcium concentration ≥ 200 ppm. For each mare, gestational length, outcome and duration of foaling, placenta expulsion time were recorded. Physical and behavioural characteristics of each foal were also recorded. Administration of oxytocin resulted in the delivery of a normal foal within 120 min in 68.9% of treated mares: 51.3% responded to the first oxytocin administration, 14.2% to the second and 3.4% to the third. No significant difference between treated and control mares was observed in the gestational length (340 ± 8 days vs 337 ± 7 days), duration of foaling (10 ± 5.6 min vs 11 ± 4.9 min), incidence of dystocia (1.4% vs 1.7%) and failure of rupture of the allantochorion (0% vs 0.6%). No significant difference was observed in the incidence of placental retention between treated and control groups (8.1% vs 6.3%). Physical and behavioural characteristics were normal in foals of both groups. In conclusion, daily injections of low doses of oxytocin in at term mares showed only moderate efficacy for inducing parturition. However, the easy applicability and the complete safety for both mare and foal, of this method of foaling induction makes it a useful tool to simplify the management of mares in commercial stud farms.  相似文献   

18.
OBJECTIVE: To identify Actinobacillus spp isolates recovered from fetuses and pericardial fluid from horses affected with mare reproductive loss syndrome (MRLS) and determine whether these bacterial species are the same as those isolated from clinically normal horses. SAMPLE POPULATION: Isolates of actinobacilli recovered from 18 horses with pericarditis and 109 fetuses aborted by mares affected by MRLS. Procedures-Actinobacillus spp isolates were identified to the level of species or subspecies by use of conventional phenotypic tests and biochemical and enzyme test kits. The 16S rRNA gene from selected isolates was amplified, purified, and sequenced. Sequence data were compared with sequence data for actinobacilli in GenBank. RESULTS: Of the 109 isolates obtained from fetuses, 14 were Actinobacillus equuli subsp equuli, 65 were A equuli subsp haemolyticus, 28 were Bisgaard taxon 10-like bacterium, and 2 were Actinobacillus genomospecies 1. Of the 18 isolates from horses with pericarditis, 4 were A equuli subsp equuli, 13 were A equuli subsp haemolyticus, and 1 was Bisgaard taxon 10-like bacterium. Comparisons with published data and GenBank data revealed that the isolates recovered from horses with MRLS were the same as those isolated from the oral cavity or alimentary tract of healthy horses. CONCLUSIONS AND CLINICAL RELEVANCE: Actinobacillus spp isolates recovered from fetuses and pericardial fluid samples of horses affected by MRLS in 2001 to 2003 were identical to Actinobacillus spp found in the oral cavity and alimentary tracts of healthy horses.  相似文献   

19.
Third-degree perineal lacerations or rectovestibular fistulae in 17 mares were repaired surgically by a one-stage method. Primary healing occurred in 14 mares; there were one complete dehiscence and two partial dehiscences with fistula formation. Twelve of 13 mares that were bred became pregnant; nine carried foals to term and two are still pregnant. Two mares have each produced one unthrifty foal. One mare repeatedly aborts in the first trimester. Four mares have produced several healthy foals with no further problems. One mare suffered further perineal trauma while foaling.  相似文献   

20.
试验旨在探究断奶前马驹和母马粪便菌群多样性,为丰富此阶段马驹肠道菌群多样性提供依据。选取5匹5岁（2胎）、平均体重（453.34±54.23）kg、健康的纯血马母马,以及母马所生的5匹马驹,出生日期相近（±5 d）,平均体重（185.65±9.54）kg,3公2母。母马和马驹在相同环境下饲养,母马日粮组成及营养水平相同,马驹除哺乳外采食的粗饲料和精料补充料相同。马驹6月龄断奶,在断奶前1周用灭菌收粪袋采集母马和马驹的粪便样品。结果显示,母马粪便中菌群α多样性Chao1和ACE指数显著高于马驹（P < 0.05）,分别比马驹高18.94%和15.62%;母马与马驹共有的菌种数为1 399个,母马与马驹特有的菌种数分别为150和68个;在门水平,母马与马驹粪便中排在前十的菌分别是厚壁菌门、变形菌门、拟杆菌门、放线菌门、广古菌门、疣微菌门、螺旋体菌门、Unidentified_Bacteria、纤维杆菌门和无壁菌门,母马粪便中厚壁菌门丰度显著高于马驹（P < 0.05）;拟杆菌门母马比马驹高33.93%,差异不显著（P > 0.05）。由此可见,母马粪便菌群多样性显著高于断奶前马驹;母马与断奶前马驹粪便主要菌是厚壁菌门、拟杆菌门和变形菌门,母马粪便中厚壁菌门和拟杆菌门丰度均高于断奶前马驹。  相似文献   

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