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1.
A serological survey for antibodies against Neospora caninum in aborting cattle was carried out in the Czech Republic. Serum samples from 463 aborting dairy cows originated from 137 farms from different parts of the Czech Republic were tested for presence of N. caninum antibodies by use of an enzyme-linked immunosorbent assay (ELISA) and an indirect fluorescent antibody test (IFAT). Antibodies (> or = 1:640) to N. caninum were found in 18 (3.9%) of 463 aborting cows. Farm prevalence in aborting cows was 12.4% (17/137). The antibody titres of cows were 1:200 (9 cows), 1:640 (7 cows), 1:1280 (3 cows), 1:2560 (3 cows), 1:5120 (3 cows), 1:10,240 (2 cows) and 1:20,480 (0 cow). A case-control study was conducted to estimate the association of N. caninum infection and abortion. For this 407 serum samples were collected from cows on five dairy farms with repeated occurrence of endemic and sporadic abortion of unidentified etiology. These samples were obtained from aborting cattle (n=44) and normally calving cattle (control group; n=363) and tested for N. caninum antibodies by an immunofluorescent antibody test (IFAT). Overall, 3.19% (13/407) of cows sampled had positive N. caninum fluorescence with a cut-off titre of 1:200. The prevalence of N. caninum was significantly higher (P<0.05) in the aborting group (13.64%; 95% confidence interval (CI): 5.2, 27.4) than in the control group (1.93%; 95% CI: 0.8, 3.9). A strong association between seropositivity and abortion was found, with seropositive cows being eight times more likely to abort than seronegative cows (odds ratio=8; 95% CI: 2.6, 25.1). This first report on the serological prevalence of N. caninum in cows in the Czech Republic verified a strong association between N. caninum infection and abortions in five dairy farms. Thus, the neosporosis should be considered in differential diagnosis of bovine abortion.  相似文献   

2.
Ultrasonographic imaging was used to monitor the effects of locoweed (Astragalus lentiginosus) on fetal, placental, and cotyledonary developments in pregnant ewes and proved to be a useful noninvasive method of monitoring the effects of locoweed poisoning on fetal and placental development. Ultrasonographic imaging may be a good research technique to observe the effects of toxicants on fetal movement, fetal heart action, and growth and development of the fetus and placenta. Known effects of locoweed poisoning in pregnant ewes, such as fluid accumulation in the placenta (hydrops allantois, hydrops amnii), altered cotyledonary development, and fetal death were observed with ultrasonographic imaging. A previously unknown effect of locoweed on fetal heart action also was observed. Locoweed decreased fetal heart rates, caused cardiac irregularity, and decreased the strength of heart contractions. All ewes, except No. 3525, fed locoweed aborted. At necropsy, aborted fetuses had hypertrophy of the heart, right ventricular dilatation, rounded at the apex of the heart, and generalized edema.  相似文献   

3.
The aim of this study was to determine the seroprevalence and presence of Chlamydia abortus in Saanen breed female goats from commercial dairy goat farms under intensive production in the municipality of Guanajuato, Mexico. Sera were collected to determine the prevalence of anti-C. abortus IgG antibodies using recombinant enzyme-linked immunosorbent assay (rELISA) and cell culture. Polymerase chain reaction (PCR) was used to prove the presence of the pathogen in swab samples collected from the vagina and rectum of selected animals. Additionally, foetal tissue samples from a sudden abortion were collected. C. abortus prevalence in female goats of commercial milking farms sampled in Guanajuato, Mexico, was 4.87 % (n?=?246). Seropositive animals were found in six out of nine (66.6 %) dairy goat farms sampled, and prevalence among animals in individual farms ranged between 3.44 and 13.51 %. C. abortus was detected using PCR in spleen tissue from the aborted foetus. PCR-based detection, as well as isolation from vaginal and rectal swabs, was not possible in the present study. Isolation through cell culture was also unsuccessful from aborted foetal tissue samples. In conclusion, the results from rELISA and PCR show that C. abortus is present in dairy goat farms in the state of Guanajuato, Mexico.  相似文献   

4.
Tropical Animal Health and Production - A cross-sectional study was conducted to determine the seroprevalence and the risk factors associated with C. burnetii infection in cattle in the state of...  相似文献   

5.
Tropical Animal Health and Production - Thirty dairy farms were selected for this study; the first objective of our study was to investigate the prevalence of subclinical bovine mastitis (SCM) in...  相似文献   

6.
To evaluate the effects of pre- and post-conception undernutrition (UN) on fetal and placental development at mid-gestation, 28 Katahdin × Pelibuey multiparous ewes were blocked by weight and assigned to the following four dietary treatments (n = 7 each): ewes fed 100% (control) or 60% of their nutritional requirements 30 days before mating (UNPre), 50 days after mating (UNPost) or during both periods (UNB). Four twin-bearing ewes were selected per treatment at day 50 post-conception and then slaughtered at day 75 of gestation to analyze their fetuses. Control fetuses were heavier (P < 0.05) than UNPost and UNB fetuses in 14.6 and 9.4%, respectively. Organ weights as percentage of the fetal weight (except for liver) and morphometric measurements (except for abdominal girth) were similar between control and UN fetuses (UNPre, UNPost, and UNB). Placental mass was heavier (P < 0.05) in control ewes than UNB ewes, but not relative to ewes of other treatments. The number of placentomes per ewe and placental efficiency were unaffected by UN treatments. Compared to control, only UNB ewes exhibited variations (P < 0.05) in the proportion of placentomes, specifically for type A (+13.8%) and B (?12.6%). Placentomes of type A and B had lower weight, length, and width of placentas in UNPost and UNB ewes than placentas of control ewes (P < 0.05). Overall results indicate that fetal and placental development of ewes carrying twins is mainly altered when nutritional restriction occurs simultaneously before conception and during the first third of pregnancy.  相似文献   

7.
A single tube nested polymerase chain reaction (PCR) assay targeting the multicopy 18S-5.8S rRNA internal transcribed spacer (ITS1) region has been developed for the diagnosis of Toxoplasma gondii-induced abortion in ovine fetal tissues. In all, 145 ovine fetal samples including brain, spleen, lung, liver, kidney, placenta and fetal fluids from 53 fetuses and stillborns of 32 farms in Northern Spain were analyzed. Thirty-six samples belonging to nine fetuses and one stillborn lamb were T. gondii PCR-positive. Although T. gondii DNA was amplified from different types of tissues, brain was the tissue with the highest detection rate. All animals that had histopathological lesions associated to T. gondii infection were positive by PCR. In addition, four fetuses whose histological examination was hindered by autolysis were PCR-positive. Results obtained by PCR and indirect fluorescent antibody test (IFAT) showed good correspondence, demonstrating the diagnostic value of the two techniques. However, PCR has the advantage over serology in its ability to diagnose T. gondii infection at earlier stages of gestation when the fetus is not yet immunocompetent and in lambs that have taken colostrum. Once other abortifacient agents are ruled out, PCR detection of the ITS1 region in fetal tissues is a valuable and relatively rapid technique for the diagnosis of ovine abortion caused by T. gondii.  相似文献   

8.
Chlamydophila abortus is an important amphixenosis which in a wide range of animals, associated with reproductive disorders in yaks. In order to assess the prevalence of this infection in yaks in Qinghai, China, a cross-sectional study was carried out, and a total of 674 serum samples were collected from June to October 2012 in six counties, and antibodies to C. abortus were examined by indirect hemagglutination (IHA) test. The overall seroprevalence of C. abortus in yaks was 17.66 % (119/674), and the seroprevalence of antibodies to C. abortus in yaks ranged from 11.82 to 28.43 % among the six different areas, and the difference was statistically significant (P?<?0.05). The seropositivity of C. abortus infection in different age groups varied from 16.33 to 18.49 %, and prevalence in yaks of ≥3 year (18.49 %) was slightly higher than that in yaks of <3 year, but the differences among the age groups were not statistically significant (P?>?0.05). The seroprevalence of C. abortus infection in male yak (16.8 %) was slightly lower than that in females (17.85 %), and the difference was not statistically significant (P?>?0.05). So far, this is the first systematic and comprehensive investigation of C. abortus infectionin in yaks in this area.  相似文献   

9.
A Chlamydophila abortus-induced abortion model was carried out on the basis of the experimental infection of ewes at day 75 of gestation. The infection induced abortions and the birth of weak lambs during the last 3 weeks of pregnancy. To study the kinetics of the infection in the placenta and in other organs, infected ewes were killed at 105, 120, and 130 days of gestation and also several days after abortion or parturition. Infected ewes developed a systemic infection that caused a mild and transient pneumonia and focal hepatitis. Pathologic changes were observed in placentas at 120 day of gestation, although the lesions varied between animals and even between placentomes of the same placenta. The first placental area infected was the maternal stroma and epithelium next to the intercaruncular areas, where neutrophilic response seemed to control the infection. A substantial degree of multiplication of C. abortus was then observed in the trophoblast cells of the placentome, periplacentomal choriallantoic membranes, and hilius, with an inflammatory exudate composed mainly of neutrophils, some macrophages, and very scarce lymphocytes. After abortion, the lesions affected the intercotyledonary areas of the aborted placentas, whereas in the uterus significant lymphocyte infiltration was observed, together with a rapid decrease of the C. abortus antigen in the degenerated caruncular tissues.  相似文献   

10.
Invasive and non-invasive strains of Chlamydia psittaci isolated from faeces of clinically healthy ewes and from vaginal swabs of ewes which had aborted were injected intravenously or intradermally into pregnant ewes. The results were studied by recording the ewes' thermal and serological responses, lambing performance and the excretion of chlamydia from the vagina. The differences between the effects of different invasive strains were greater after intradermal inoculation than after intravenous inoculation. After intradermal inoculation non-invasive strains did not disturb pregnancy (11 of 13 ewes lambed normally) whereas invasive strains induced abortion in 23 of 25 ewes, 24 of which excreted chlamydia in vaginal secretions.  相似文献   

11.
A preliminary serological study of 366 household dogs in Lagos and Ibadan, southwestern Nigeria, was carried out to determine antibodies due to exposure to Brucella abortus and B. canis, using the rose bengal test (RBT) and the rapid slide agglutination (RSA) test, respectively. Results showed that 5.46 % (20/366) and 0.27 % (1/366) of the dogs screened were seropositive to B. abortus and B. canis, respectively. Of all dogs, 36 had a history of being fed foetuses from cows and 11 (30.6 %) of these tested positive in the RBT. Our findings, although based on a limited sample size and a dearth of clinical details, revealed that dogs in Nigeria may be infected with Brucella spp. given the wide range of risk factors. Further studies are recommended to elucidate the epidemiology of brucellosis in dogs and its possible zoonotic consequences in the country.  相似文献   

12.
13.
A wide range of variation in concentration of manganese was found in the blood of 51 cycling ewes although no significant differences were evident (P less than 0.05) between days 4, 11 and 15 (day 0 = day of estrus) of the estrous cycle. In addition, no differences (P less than 0.05) were found in the manganese concentrations of various soft tissues of 15 ewes, killed on day 4 (five animals), day 11 (five animals) or during anestrus (five animals). The highest concentration of manganese was present in the liver, pancreas and kidney cortex, tissues which are rich in mitochondria. Among the tissues of the reproductive tract, the corpus luteum showed the highest manganese concentration and the level increased significantly (P less than 0.01) between days 4 and 11 suggesting that this trace element may be closely related to the metabolic and possible functional characteristics of this endocrine gland. Uterine horn and caruncles contained greater manganese concentrations than other components of the reproductive tract. The significance of these findings in relation to the effect of manganese intake on ewe fertility remains to be assessed.  相似文献   

14.
In the present study, the seroprevalence and genetic identification of Mycoplasma ovipneumoniae infection in goats were investigated in Hainan Province, tropical China between October 2012 and October 2013. A total of 1,210 serum samples collected from 16 herds in various administrative regions in tropical China were evaluated using indirect hemagglutination assay (IHA). Antibodies to M. ovipneumoniae were tested in (31.7 %, 95 % confidence interval (CI) 29–34.3) 383 of 1,210 serum samples (IHA titer ≥1:16). The M. ovipneumoniae seroprevalence ranged from 26.8 % (95 % CI 20.8–32.9) to 39 % (95 % CI 30.8–47.2) among different regions in tropical China, and the difference was statistically significant (P?<?0.01). The seroprevalence of M. ovipneumoniae infection in goats was higher in winter (46.1 %, 95 % CI 39.6–52.5) and spring (33.8 %, 95 % CI 28.3–39.3) than in autumn (27.5 %, 95 % CI 22.6–32.3) and summer (24.7 %, 95 % CI 20.3–29.1), and the difference was statistically significant (P?<?0.01). In addition, DNA was extracted from nasal swab; lung samples and the 16S rRNA gene sequences were amplified by polymerase chain reaction (PCR) and then sequenced. Twenty-four of 329 (7.3 %) nasal swab samples and 73 of 280 (26.1 %) pneumonic lung tissues were found to contain M. ovipneumoniae, respectively. The results of the present survey indicate that M. ovipneumoniae infection is highly prevalent in goats in tropical China. This is the first report of the comprehensive survey of M. ovipneumoniae prevalence in goats in China.  相似文献   

15.
Fetal amino acid nutrition and metabolism have been studied primarily in pregnant sheep. The umbilical uptake of amino acids changes during gestation, but at both mid- and late gestation the total supply exceeds that required for growth. Weight-specific protein synthetic rate decreases with increasing gestational age, and these changes are proportional to the changes in metabolic rate. The use of multiple tracer methodology coupled with measurement of net tracer fluxes into and out of fetal and placental tissues can be used to delineate amino acid metabolism in considerable detail. Such studies demonstrate that even essential amino acids can be oxidized extensively by the fetus. The oxidation rate of leucine exceeds its rate of accretion in tissue proteins. Glycine metabolism is unique in several ways; there is a large umbilical uptake of glycine without a measurable uterine uptake. In late gestation there is no significant umbilical uptake of serine, although there is a significant uterine uptake, suggesting net uteroplacental utilization. Glycine is oxidized within the fetal liver and used for serum production. The interorgan exchange of amino acids between the fetal liver and placenta is clearly of major importance for serine and glycine metabolism and is likely to be of major importance for most nonessential amino acids.  相似文献   

16.
In total, 796 serum samples of sheep on commune alpine pastures in the region of Vorarlberg were investigated by a commercial ELISA kit for antibodies against Chlamydia abortus, the agent of ovine enzootic abortion. The aim of the study was to determine the seroprevalence within this region and to compare these results with the seroprevalence in the neighboring canton Graubünden as well as to obtain data on the seroconversion after alpine pasturing. Therefore, 421 samples were collected before and 375 samples after alpine pasturing, whereas corresponding serum samples were available from 359 sheep. Within the region of Vorarlberg, a mean seroprevalence of 9.2 % was calculated with a threshold of 60 %. Seroconversion for C. abortus occurred in 5.0 % of animals with corresponding serum samples. Seroprevalence values were comparable to Swiss regions with similar management systems, although the neighboring canton Graubünden is known to have a much more higher seroprevalence of 43 %. In conclusion, the traditional animal exchange between these two regions is not significantly favoring the spread of C. abortus.  相似文献   

17.
Before birth a marked rise in the potassium/sodium concentration ratio of allantoic fluid coincided with a similar rise in the corticosteroid levels of fetal plasma. The prepartum corticosteroid increase started at 134-136 days gestational age whether delivery occurred at 141 or 151 days.  相似文献   

18.
Growth and compositional changes of fetal tissues in pigs   总被引:2,自引:0,他引:2  
Three hundred twenty fetuses were obtained from 33 pregnant gilts (Camborough-22, Pig Improvement Co.) to determine rates of nutrient deposition in fetal tissues and to estimate nutrient requirements for fetal growth. Pregnant gilts were fed an equal amount of a gestation diet (2.0 kg/d; as-fed basis), and were slaughtered at d 0, 45, 60, 75, 90, 102, or 110 of gestation (n = 3 to 6 per day). Fetuses were dissected into carcass and individual tissues (including gastrointestinal tract, liver, lung, heart, kidney, spleen [> or = d 75]), and partial placental collection was made for chemical analysis. Fetal tissues were weighed and analyzed for DM, ash, CP, and crude fat. Regression equations were obtained to explain the weight and compositional changes of individual tissues during gestation. Weights of the fetus, carcass, gastrointestinal tract, liver, heart, lung, and kidney increased cubically (P < 0.001), whereas brain weight increased linearly (P < 0.001) as gestation progressed. Fetal protein and fat contents increased quadratically (P < 0.001) as gestation progressed (R2 = 0.906 and 0.904, respectively). Changes in fetal protein and fat contents fit a multiphasic regression that consisted of two linear equations (P < 0.001, R2 = 0.988 and P < 0.001, R2 = 0.983, respectively), indicating that protein and fat growth accelerated after d 69 of gestation. Fetal protein and fat accretions were 0.25 and 0.06 g/d (P < 0.001) before d 69 of gestation, and increased to 4.63 and 1.09 g/d (P < 0.001) after d 69 of gestation. Protein needs for tissue protein gains increased 19-fold after d 69 of gestation. Results of this study indicate that the growth of the fetus and fetal tissues occurs at different rates during gestation and support the practice of a two-phase feeding strategy (before and after approximately d 70 of gestation) for pregnant gilts.  相似文献   

19.
The concentration of bovine placental lactogen (bPL) was determined in fetal placentomes, allantoic fluid, amniotic fluid, maternal and fetal plasma throughout pregnancy. In addition, chromatofocusing chromatography was used to separate the different forms of bPL found both in fetal serum and in placental homogenates in order to determine whether the different forms that have been reported to exist in the cotyledon are also found in the fetal circulation. Reproductive tracts were collected from cows between 109 and 247 days of pregnancy. The concentration of bPL in the fetal cotyledonary tissue was measured by both radioreceptor assay and radioimmunoassay, both assays showed that the concentration of bPL in the fetal portion of the placentomes remained constant throughout the period of pregnancy tested. The mass of the placenta increased approximately 10-fold during the period of study but the concentration of bPL in the maternal plasma was low (0.9±0.1 ng/ml) at all stages of pregnancy tested. The mean concentration of bPL (Mean ± S.E.M.) in amniotic and allantoic fluid was 0.4±0.1 and 1.2±0.2 ng/ml respectively. Fetal blood contained the highest concentrations of bPL, from 11.6 to 18.4 ng/ml, and the concentration tended to decrease with advancing gestation (slope = 0.07, P = 0.001). Several forms of bPL were found in the fetal circulation; however, a higher percentage of forms with more acidic isoelectric points were found in the fetal serum than in placental homogenates. These results suggest that either some forms of bPL are more stable or that the hormone isolated from placental tissue is not representative of the final secreted product.  相似文献   

20.
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   

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