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1.
To investigate the risk factors for neonatal calf diarrhoea, a cross-sectional study was conducted on 97 New Zealand dairy farms. Faecal specimens from 1283 calves were scored as liquid, semi-solid or solid, and analysed for bovine rotavirus (BRV) and coronavirus (BCV), enterotoxigenic K99+ Escherichia coli (K99), Salmonella spp. and Cryptosporidium parvum. Calf- and farm-level data were collected by means of a questionnaire and the odds of liquid faeces calculated using mixed effects logistic regression models.Among the infectious agents, only C. parvum (odds ratio [OR] = 2.6; 95% confidence interval [CI], 1.3–5.6; P = 0.02), BRV (OR = 2.7; 95% CI, 1.3–5.9; P = 0.01) and co-infection with more than one agent (compared with mono-infection: OR = 2.5; 95% CI, 1.3–4.8; P = 0.01) were associated with increased odds of liquid faeces in calves which were 9 to 21 days old. Housing of calves in open barns so exposing them to the weather was also associated with increased odds of liquid faeces compared with closed barns (OR = 2.1; 95% CI, 1.1–12.2; P = 0.03). Vaccinating cows against calf enteropathogens (OR = 0.2; 95% CI, 0.1–0.9; P = 0.03), administering waste milk (from mastitis and/or containing antibiotics; OR = 0.4; 95% CI, 0.1–0.8; P = 0.01), the sex of calves (females compared to males OR = 0.2, 95% CI, 0.07–0.7; P <0.01), and the use of straw for bedding (OR = 0.2; 95% CI, 0.03–0.9; P = 0.03) decreased the odds of liquid faeces. Conversely, in calves that were 1 to 5 days old, only K99 was associated with liquid faeces (OR = 4.6; 95% CI, 1.2–16.1; P = 0.02). In this age group, the odds of liquid faeces were smaller on farms where females took care of the calves, compared with males (OR = 0.4; 95% CI, 0.01–0.9; P = 0.04).  相似文献   

2.
The aim of this study was to determine the herd prevalence of veal and dairy herds and to identify risk factors for VTEC O157 positive veal herds. The study was based on monitoring data from November 1996 through July 2005 of 1051 dairy herds and 930 veal herds. The herd level prevalence (95% CI) was 8.0% (6.4–9.6) for dairy herds and 12.6% (10.5–14.7) for veal herds. Within the population of veal herds, a prevalence of 39.8% (33.9–45.6) was found for pink veal herds (n = 269) and 1.5% (0.7–2.8) for white veal herds (n = 661).Multivariable logistic regression showed that the type of veal (pink vs. white; OR = 21.6; 95% CI: 10.4–45.0), ventilation (mechanical vs. natural; OR = 0.4; 95% CI: 0.2–0.8), time between arrival in the herd and sampling (3–5 months vs. 0–2 months: OR = 2.33; 95% CI: 1.1–5.1, ≥6 months vs. 0–2 months: OR = 4.11; CI: 1.9–8.9), other feed than the 7 most common (yes vs. no; OR = 2.1; 95% CI: 1.2–3.7) and at least one dog present in the stable (yes vs. no; OR = 2.6; 95% CI: 1.5–4.6) were significantly (P < 0.05) associated with the presence of VTEC O157. The large difference in the VTEC O157 prevalences for pink veal and white veal production might have been caused by a very different management of these type of herds. However, this could not be studied with the data collected.  相似文献   

3.
Cystic echinococcosis is a major emerging zoonosis in many Eastern European and Asian countries. Post slaughter examinations of 684 pig livers in Lithuania revealed significantly higher numbers of Echinococcus granulosus infections in animals from family farms (13.2%; 95% CI 10.7–16.2) as compared with those from industrial farms (4.1%; 95% CI 0.8–11.5). The prevalence was also significantly higher in pigs older than 1 year than in younger ones. In addition, in 0.5% of the pigs from the family farms, infertile and calcified E. multilocularis lesions were identified by PCR. Faecal samples from rural dogs (n = 240) originating from 177 family farms in 12 villages were investigated for taeniid eggs with two methods. Significantly more dogs excreting taeniid eggs were diagnosed with the flotation/sieving method (n = 34) as compared to the modified McMaster method (n = 12). Multiplex PCR performed with DNA from taeniid eggs isolated from faeces of 34 dogs revealed 26 infections with Taenia spp., 9 with E. granulosus and 2 with E. multilocularis (4 cases with concurrent Taenia spp. and E. granulosus or E. multilocularis infections). Genotyping of E. granulosus cyst tissues from 7 pigs, 1 head of cattle and from E. granulosus eggs from 8 dog faeces revealed the genotype G6/7 (‘pig/camel strain’) in all cases. The high infection pressure with Echinococcus spp. in family farms necessitates initiating control programs.  相似文献   

4.
Bovine tuberculosis (bTB) is a continuing problem in British herds. Micro-nutrients are important for the maintenance of well-functioning immune system. The aim of this study was to determine whether the selenium, copper and vitamin B12 status of cattle was associated with Mycobacterium bovis (M. bovis) infection. Between 2002 and 2005, 200 cattle (43% dairy, mean age 4.6 years), reactors according to the standard interpretation of the tuberculin test, and 200 in-contacts (41% dairy, mean age 4.4 years) non-reactors, which had been in contact with cattle with bTB, were selected from herds in England and Wales. Levels of the seleno enzyme glutathione peroxidase (GSHPx), copper and vitamin B12 were measured in blood. Confirmation of bTB infection was made by bacteriological culture and histopathology following a detailed postmortem. Levels of selenium and copper were also measured in a random sample of 63 livers. bTB was confirmed by culture/histology in 23/200 (11.5%) of in-contacts and 110/200 (55%) of reactors. In blood drawn at recruitment, GSHPx was lower in cattle with confirmed bTB compared to other cattle (geometric means 59.7 u/mL versus 78.9 u/mL red blood cells (RBC), p < 0.01). Vitamin B12 was similar (geometric means 161.5 pmol/L versus 165.5 pmol/L, p = 0.62) and copper was similar (geometric means 14.4 μmol/L versus 14.1 μmol/L, p = 0.55). In logistic regression models including all micro-nutrients simultaneously and controlling for age, sex, animal production class, herd size, number of reactors, postmortem laboratory and seasonal trends, lower levels of GSHPx (adjusted OR 0.42, 95% CI 0.21–0.81 per 100 u/mL RBC, p = 0.01) and higher levels of copper (adjusted OR 1.69, 95% CI 1.21–2.36 per 5 μmol/L, p < 0.01) were associated with an increased risk of confirmed bTB but there was no association with vitamin B12. There was evidence for a stronger association between confirmed bTB and GSHPx in in-contacts (adjusted OR 0.21, 95% CI 0.06–0.79 per 100 u/mL RBC) compared to reactors (adjusted OR 0.50, 95% CI 0.21–1.23 per 100 u/mL RBC) (p = 0.08 for interaction). Lower liver copper was associated with a higher risk of confirmed bTB (adjusted OR 0.15, 95% CI 0.02–1.0 per 5000 μmol/kg dry mass, p = 0.05) but there was no association between liver selenium and bTB. Trace micro-nutrient status may affect susceptibility to M. bovis infection in cattle. Further studies are needed.  相似文献   

5.
Fluoroquinolones are used to treat infections caused by Escherichia coli in canine and feline veterinary patients, particularly those infecting the urinary tract. The gyrA gene is a primary target causing fluoroquinolone resistance in Gram negative coliforms, with mutations in codons 83 and 87 generally associated with high-level of resistance E. coli clinical isolates. We have developed a fluorescence resonance energy transfer (FRET) quantitative PCR to identify enrofloxacin-resistance in clinical E. coli isolates that carry mutations in codons 83 and 87 of gyrA. This real-time quantitative PCR assay is rapid, economical, and sensitive compared with cultured antimicrobial susceptibility testing. The assay identified as few as four genome copies per reaction from culture and 19 genome copies in urine. For the 70 isolates tested, the sensitivity was 87.5% (95% CI = 75–95.3%) (n = 42/48), specificity was 100% (95% CI = 87.3–100%) (n = 22/22), whereas accuracy was 91.4% (95% CI = 82.3–97%) (n = 64/70). Furthermore, we were able to accurately differentiate between the wild type and mutants E. coli directly from infected canine urine samples (n = 5) within 2 h. These results were confirmed by sequence alignments of the PCR products and comparison with the susceptibility testing. The FRET-PCR assay appears to have promising clinical application as an early diagnostic tool for rapid and sensitive detection and differentiation of the level of fluoroquinolone resistance among clinical E. coli isolates that may facilitate design of the dosing regimen.  相似文献   

6.
Four Nili-Ravi buffalo calves (100 ± 4 kg) were used in 4 × 4 Latin Square Design to evaluate the influence of varying ruminally degradable protein (RDP) to ruminally undegradable protein (RUP) ratio on dry matter intake (DMI), digestibility and nitrogen (N) metabolism. Four experimental diets A, B, C and D were formulated to contain RDP:RUP of 70:30, 65:35, 60:40 and 55:45, respectively. The calves were fed ad libitum. Dry matter intake by calves fed C diet was higher (P < 0.05) than those fed D diet and lower (P < 0.05) than calves fed A diet, however, it was similar to those fed B diet. There was a linear decrease (P < 0.01) in DMI with decreasing the RDP to RUP ratio. Similar trend was noticed in crude protein (CP) intake. Neutral detergent fiber (NDF) intake was significantly different across all treatment. The decrease in CP and NDF intake was due to decreasing trend of DMI. Dry matter (DM) digestibility in calves fed A and B diets was higher (P < 0.05) than those fed C and D diets. A linear decrease (P < 0.01) in DM digestibility was observed with decreasing the RDP to RUP ratio. Crude protein digestibility remained unaltered across all treatments. Neutral detergent fiber digestibility was higher in calves fed A and B diets than those fed C and D diets. Higher NDF digestibility in calves fed A and B diets was due to higher level of dietary RDP that might resulted in higher ruminal ammonia concentration which stimulate activity of cellulytic bacteria and ultimately increased NDF digestibility. The N retention (g/d) was similar among the calves fed B, C and D diets, however, it was higher (P < 0.05) than those fed A diet. Decreasing the RDP to RUP ratio resulted in linear increase (P < 0.01) in N retention. The N retention, as percent of N intake was significantly different across all treatments. Decreasing RDP to RUP ratio resulted in linear increase (P < 0.01) in N retention, as percent of N intake. A similar trend was noticed in N retention, as percentage of N digestion. Blood urea nitrogen (BUN) concentration in calves fed B diet was higher (P < 0.05) than those fed D diet and was lower (P < 0.05) than those fed A diet, however, it was not different from calves fed C diet. Decreasing dietary RDP to RUP ratio resulted in linear decrease (P < 0.05) in BUN concentrations. The decrease in BUN concentration was because of decreasing level of dietary RDP. The N retention can be increased by decreasing RDP to RUP ratio in the diet of growing buffalo calves and diet containing RDP to RUP ratio 55:45 is considered optimum regarding N retention in buffalo calves.  相似文献   

7.
The effect of management on the seroprevalence of Babesia bovis was studied in 399 Bos indicus cattle 1–2 years old from 92 farms in the eastern Yucatán, México. The management factors studied were: farm-type, production system, herd size, farm size, stocking density, vector control, dipping interval, type of dipping, type of acaricide and cattle introduction to the farm. A cross-sectional study was carried out (2-stage cluster sampling). The number of serum samples was proportionally distributed according to the number of farms in the nine locations of eastern Yucatán, México (399 animals from 92 farms). Antibody activity to B. bovis was tested using an indirect ELISA. The farms with a seroprevalence ≤75% were considered as cases and those with seroprevalence >75% were considered as controls. The variables with p ≤ 0.20 were included in fixed effects logistic regression. The seroprevalence of the zone was 73.8% (66.3–81.3%). The following risk factors were found: Stocking density (<1 head/ha, OR = 4.04, CI (OR) = 1.20–13.62) and dipping interval (>60 days, OR = 5.07 CI (OR) = 1.26–20.48).  相似文献   

8.
The present study was conducted to investigate the effects of Acanthopanax senticosus extract (ASE) as a dietary additive on gut health in weanling piglets by examining diarrhea frequency, intestinal microbiota and morphology. A total of 96 Duroc× (Landrace × Yorkshire) piglets weaned at 21 days of age with an average initial body weight (BW) of 5.6 ± 0.4 kg were randomly assigned to 3 treatment groups with 4 duplicates of 8 piglets each. The piglets were fed basal diet to which had been added 0 or 1 g/kg of ASE, or 0.7 g/kg antibiotics, respectively. Fecal consistence was monitored twice daily and the frequency of diarrhea was calculated. On day 21 after the initiation of supplementation, 8 piglets were randomly selected from each treatment group (2 piglets per pen) and slaughtered. The jejunum, ileum, colon and cecum were then excised and fixed in 10% neutral formalin solution to determine villus height and crypt depth, after their contents were collected to determine microbiota. The results showed that dietary supplementation with ASE increased (P < 0.05) the density of bacterial populations that co-migrated with Lactobacillus amylovorus, Lactobacillus salivarius, Bacillus subtilis, and Clostridium lituseburens, but decreased (P < 0.05) those co-migrating with Staphylococcus aureus, Salmonella typhimurium, Ruminococcus forques, and E. coli O157:H7 in the PCR-DGGE profiling analysis when compared with the control group. The villus height of the duodenum, jejunum and ileum increased (P < 0.05) by 14.8, 13.7 and 10.0%, while the crypt depth decreased (P < 0.05) by 17.9, 9.1 and 12.1%, respectively, in response to dietary ASE supplementation. Additionally dietary supplementation with ASE or an antibiotic decreased (P < 0.05) the frequency of diarrhea by 55.6 and 52.2%, respectively, compared with the control group. In conclusion, these findings suggest that dietary supplementation with ASE could regulate the microbiota composition and maintain a normal morphology of gut mucosa in weanling piglets, thereby decreasing diarrhea that resulted from weaning stress.  相似文献   

9.
Medium-chain fatty acids (MCFAs) have antialgal, antibacterial, antifungal, antiprotozoan, and antiviral activities. However, antibacterial activities of MCFAs in the hindgut of pigs and cattle are still unknown. We report the effects of the supplementation of MCFAs on fecal bacteria of pigs, lactating cows, and Japanese Black calves. Lactobacillus spp., Bifidobacterium spp., eaeA(+) Escherichia coli, Salmonella spp., Campylobacter jejuni, and Clostridium perfringens in the feces of animals were quantified by real-time PCR assay. There was no significant increase or decrease in Lactobacillus spp. and Bifidobacterium spp. in the three animals. In the pig feces, eaeA(+) E. coli was reduced to less than a third in the treatment group (P < 0.01). C. jejuni in the pig feces was also significantly less in the treatment group compared with the control (P < 0.01). In the lactating cow, eaeA(+) E. coli was reduced to one fifth of that in the control (P < 0.01). Salmonella spp. was halved in calf feces (P < 0.01). Thus, a reduction in Gram-negative pathogenic bacteria was observed. In conclusion, supplementation of a MCFA calcium soap in the diet would be beneficial to growing pigs, lactating cow, and calves by reducing pathogenic bacteria.  相似文献   

10.
The aim of this study was to determine the prevalence, variability with host age, and the genotypes of species of Cryptosporidium in cattle from 15 dairy farms in Qazvin province, Iran. Fecal samples, collected from 272 cattle during May 2006 to December 2007, were characterized microscopically. Oocysts from 51 positive samples were analyzed using PCR assay of 18S SSU rRNA, restriction fragment length polymorphism (RFLP) and sequencing. We identified 72.6% of the positive samples as Cryptosporidium parvum, 17.7% as Cryptosporidium andersoni, 7.8% as Cryptosporidium bovis and 1.9% as a novel genotype of C. parvum possessing a single mutation on MboII restriction. An infection rate of 19.5% of C. parvum among 174 pre-weaned calves was significantly higher than the 3.1% among 98 post-weaned calves (P < 0.0006). This is the first report of C. bovis and the new subgenotype of C. parvum in Iranian cattle.  相似文献   

11.
The objective of this study was to evaluate the influence of different feed withdrawal and lairage times prior to slaughter on the gastrointestinal tract (GIT) weight and on the fermentation pattern and numbers of Enterobacteriaceae in the cecum of pigs. A total of 72 finishing pigs (6 pens, 12 animals each) were included in the study and were sent to the slaughterhouse on three consecutive days. On each day pigs from two pens were deprived of feed for either 2 or 12 h before leaving the farm. Pigs from each of the two pens were divided in sub-groups (4 pigs each) on the moment of loading onto the truck and followed the same distribution at the slaughterhouse. Once there, each sub-group corresponding to the same feed withdrawal time was held in different holding pens for 0, 5 or 10 h before slaughter. The weight of the gastro-intestinal tract (GIT) was determined and cecal content was collected to evaluate pH, short chain fatty acids (SCFA) and ammonia (NH3) concentrations as well as lactobacilli and Enterobacteriaceae numbers. Total GIT weight decreased as feed withdrawal (P < 0.0001) and lairage time (P < 0.001) increased within a range between 6.69 and 4.59 kg. Cecal pH increased with feed withdrawal (P < 0.0001) and lairage time (P = 0.0001) (ranging from 5.79 to 6.79) in parallel to a decrease in the total SCFA concentration (P < 0.005) (from 211 to 100 mM). The percentages of acetic and propionic acid were not modified by the experimental treatments but significant decreases were registered in the percentage of butyric acid with the increased times of both withdrawal (P < 0.0001) and lairage (P < 0.005). The percentage of valeric and branched SCFA and also NH3 concentration showed an increase with withdrawal (P < 0.005, P < 0.0001 and P < 0.005 respectively) and lairage (P < 0.005, P < 0.0001 and P < 0.001 respectively). Lactobacilli numbers decreased as lairage time increased (from 9.97 to 8.63 log 16S rRNA gene copies/g FM; P < 0.05) and Enterobacteriaceae numbers increased with both, feed withdrawal (P < 0.05) and lairage (P < 0.05) (ranging from 8.53 to 9.95 log 16S rRNA gene copies/g FM).The previous to slaughter increase in feed withdrawal and lairage times decreased the GIT weight but involved changes in the gut microbial ecosystem caused through changes in the fermentation pattern that lead to the increase of Enterobacteriaceae numbers. This increase could represent a higher risk of carcass contamination by the enteropathogens of this group such as Salmonella. However this potential risk should be further investigated.  相似文献   

12.
Captive reptiles are routinely identified as reservoirs of Salmonella spp. and reports of reptile-associated salmonellosis are increasing. Unfortunately, little is known about the epidemiology of Salmonella spp. and green iguanas. We did a limited survey of a green-iguana farm in El Salvador to identify sources of Salmonella spp. in green iguanas and their environment. A limited number of samples for microbiological culture were collected from iguanas (adult, hatchling, and embryos) and their environment (food, water, soil, shelter, insects, and wild-caught lizards). Salmonella spp. was isolated from the intestine of both adult (3/20) and hatchling iguanas (8/20). There was no evidence of Salmonella spp. in the reproductive tracts of female iguanas (0/10). Salmonella spp. was isolated from the surface of 40% (7/16) of the egg surfaces tested. Salmonella spp. was not identified from the externalized yolk-sac of the iguana embryos tested. Soil samples from a breeding pen and a nest were both positive for Salmonella spp. Eight different Salmonella spp. serotypes were identified in this survey. These results suggest that horizontal transmission of Salmonella spp. is a potential source of exposure to hatchling iguanas at this facility.  相似文献   

13.
The aim of the study was to evaluate the protection generated in mice against Toxoplasma gondii brain cyst burden by vaccination with T. gondii cytoskeleton proteins using Lactobacillus casei as adjuvant. One hundred and sixty-eight NIH mice were randomly allocated into eight groups of 21 mice each. Animals were immunized as follows: in group 1 with Toxoplasma lysate antigen (TLA) in Freund's modified adjuvant, containing L. casei (FMA), in group 2 with Toxoplasma cytoskeleton proteins (TCPs) in FMA, in group 3 with FMA, in group 4 with phosphate buffered saline (PBS), in group 5 with L. casei dead by heath (Lc), in group 6 with Freund's complete adjuvant (FCA), in group 7 with TLA in FCA, and in group 8 with TCP in FCA. Mean brain cyst burden (±S.E.M.) was assessed in mice 8 weeks after challenge with T. gondii Me49 strain (20 cysts per mouse). The percentages of reduction in cyst burden per brain (P < 0.01) as compared with the group 4 (control: mean 3181 ± 97.5) were 77.25% (724 ± 98) in group 1, 88.02% (381 ± 97.5) in group 2, 38.92% (1943 ± 130.3) in group 3, 44.31% (1771.4 ± 102) in group 5, 59.28% (1295.2 ± 99.1) in group 7 and 55.69% (1409.5 ± 89.9) in group 8. In order of importance, the best protection was obtained in groups 2, 1, 7, 8, 5 and 3. Noticeably the mice inoculated with L. casei alone showed a significant reduction in T. gondii brain cysts (P < 0.01), while those animals treated with FCA alone did not. Additionally, IgM anti-T. gondii antibody levels, as determined by ELISA 2 weeks after challenge, were highest in group 2 (P < 0.01) than in the other seven groups. Results suggest that T. gondii cytoskeleton proteins with L. casei as adjuvant constitute a good anti-toxoplasmosis vaccine candidate.  相似文献   

14.
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15.
The present study investigates, under field conditions, the influence of antimicrobial administration on prevalence and patterns of antimicrobial resistance among Escherichia coli and Enterococcus spp. isolated from growing broilers. For this purpose, a group of 16,000 commercial broiler chickens was treated with enrofloxacin from day 1 to day 3, gentamicin from day 19 to day 21, and ampicillin from day 26 to day 28. A control group of 16,000 broilers was placed in the same controlled environment poultry house. Fecal (from both groups) and feed samples were collected at regular intervals. Few E. coli isolates were obtained from either farm environment or poultry feed samples, while enterococci were found to be ubiquitous among these samples. The frequency of resistance against most antimicrobials tested was significantly higher (P < 0.05) in E. coli isolated from broilers receiving intermittent antimicrobial pressure than that from non-medicated broilers, whereas in enterococci these differences were only observed among structurally related antimicrobial drugs and over a short period of time. By the time the broilers reached market age (33 days), several multi-resistant E. coli and enterococci were detected in the feces of the medicated group. Results suggest that antimicrobial resistance in E. coli was mainly medication-dependent, whereas among enterococci, changes observed over time were apparently influenced by factors apart from antimicrobial exposure, namely the resistance organisms previously present in farm environment and those present in feedstuffs.  相似文献   

16.
Sixteen West African dwarf goats weighing 5.0–5.6 kg were used in an experiment that lasted 112 days to investigate the utilization of citrus pulp based diets and E. cyclocarpum. A control diet which contained 88.5% dried brewers' grains (DBG) and other three experimental diets in which DBG was replaced with dried citrus pulp (DCP) at 25, 50 and 75% levels, respectively constituted the four treatments. The goats were divided into four groups of four animals each to balance for variation in live weight before they were assigned to the four different experimental diets. Significant differences (P < 0.05) were obtained in growth rate with (22.14–34.02 g/d) the highest and lowest value from 50 and 75% DCP inclusion respectively. The digestibility coefficients of DM, Ash, NFE, NDF, ADL, cellulose and hemicellulose increased with increasing levels of dried citrus pulp in the diets and were highest at 75% level of replacement. However, the CP digestibility of 83.85% was highest in the control diet and was significantly (P < 0.05) different from other diets containing citrus pulp. Nitrogen intake (g/d) decreased significantly (P < 0.05) with increasing levels of dried citrus pulp in the diets from 45.57–33.28 and was lowest in the control diet. Nitrogen balance also followed the same trend, being highest (42.07 g/d) at 25% DCP and lowest at 75% DCP. The Packed cell volume (PCV), haemoglobin concentration (Hb), red blood cells (RBC), white blood cells (WBC) and total blood protein (TBP) were significantly (P < 0.05) different across the dietary treatments at the start and end of the trial. The values for PCV, RBC, MCH, glucose and total protein decreased slightly in the control diet. Serum glutamate pyruvate transaminase (SGPT) values also increased significantly (P < 0.05) with increasing levels of dried citrus pulp in the diets at the end of the experiment and were highest (6.50 IU/L) at 75% level of citrus pulp. Therefore, the efficient utilization of citrus pulp and E. cyclocarpum by WAD goats was attained at the 50% level of inclusion in the diets.  相似文献   

17.

The present study attempted to verify the prevalence of and risk factors for diarrhea-causing agents in dairy calves from Brazil. Additionally, ages with a higher risk of occurrence for each agent were verified by means of the receiver operating characteristic (ROC) curve. The collections were performed on 39 farms, belonging to 29 municipalities located in eight states of Brazil. It was possible to conclude that the prevalence of Coronavirus, Rotavirus, Cryptosporidium spp., Eimeria spp., and nematodes was 7.20% (95% CI 4.54–9.78), 6.37% (95% CI 3.85–8.89), 51.52% (95% CI 45.26–55.57), 3.46% (95% CI 2.24–4.67), and 3.46% (95% CI 2.24–4.67), respectively. Ages with higher probabilities of occurrence of these diseases in calves were <?10, >?8, >?6, >?37, and >?36 days, respectively. Diarrhea occurred more significantly (P?<?0.0001) in animals less than 21 days old and mainly on those receiving milk through automatic feeders (P?<?0.001). Cryptosporidium spp. were a risk factor for the occurrence of Rotavirus, and vice versa (P?=?0.0039) and presented a positive correlation with Coronavirus (P?=?0.0089). Calves that drink water from rivers, streams, and ponds had a higher chance of being infected by Eimeria spp. (P?<?0.0001), as well as developing infection by nematodes (P?<?0.0001). The results found in this study highlight the importance of studying the agents of diarrhea together, once they act as coinfection where the losses triggered for the owners will involve some of these agents simultaneously.

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18.
Fecal samples from 67 3–5-months-old calves with diarrhea were screened for the presence of shiga toxin-producing Escherichia coli (STEC). Several accessory virulence factors genes were also tested. Among 192 E.coli isolates tested, 15 (7.6%) were found to harbour the shiga toxin 1 or 2 (stx1 or stx2) genes. The stx2-carrying samples were further subtyped by PCR for the stx2c, stx2d, and stx2e toxin variants. It was shown that stx2-positive bacteria mainly possessed the stx2c shiga toxin type gene. The enterohemolysin (hlyA) and intimin (eae) genes were found in seven (46.7%) STEC strains whereas the cytotoxic necrotizin factor 1 and 2 or the P fimbrial genes were detected in two isolates only. This study confirmed that calves are a reservoir of STEC strains (with all pathogenicity genes) that may be virulent for humans.  相似文献   

19.
A grazing experiment was undertaken to evaluate the effect of PEG supplementation on the fatty acid composition of milk from Sarda sheep grazing sulla. Twenty-four late-lactating sheep (12 per group), were paired and split into two groups: group control (CON), dosed daily with a quenching gun with 200 ml of water, and group PEG, dosed with 200 ml of a 50/50 w/v water solution of PEG. The sheep grazed two 0.8 ha plots of sulla under a rotational grazing scheme.The contents of c-9, t-11 CLA and t-11 C18:1 in milk fat were on average 40% higher (P < 0.01) in the PEG group than in the CON group. This can be explained by the higher biohydrogenation activity of ruminal bacteria in the PEG group, due to the partial inactivation of the tannins. Odd-branched chain fatty acids (OBCFA) were higher in PEG than in the control group (+ 20%; P < 0.01) and this confirms the hypothesis that tannin in sulla reduced ruminal microbial activity. Both linoleic (C18:2 c-9 c-12) and linolenic (C18:3 c-9 c-12 c-15) fatty acids were lower (P < 0.05) in milk from PEG, than in the CON-group (− 12% and − 30% for linoleic and linolenic acids, respectively). The mitigating effect on tannins of PEG increased the ratio of ω6/ω3 by 24%; (P < 0.01) and total trans FA content in milk by 20% (P < 0.01). In conclusion, condensed tannins in sulla at flowering are conducive to lower c-9, t-11 CLA and t-11 C18:1 but also lower total trans FA, ω6/ω3 ratio and higher linoleic and linolenic acid.  相似文献   

20.
Gastric Helicobacter spp. are associated with chronic inflammation and neoplastic transformation in humans as well as domestic and laboratory species. The present study examined the association of Helicobacter heilmannii (Hhe) infection in pet cats with feline gastric mucosa associated lymphoid tissue (MALT) lymphoma. Tissues were collected via gastric biopsy or at necropsy from 47 pet cats with clinical signs of gastrointestinal disease, including vomiting and inappetance, and classified as gastritis (14/47), lymphoma (31/37), or normal (2/47). Tissues positive for argyrophilic organisms with Warthin–Starry stain (29/47) were assessed by fluorescent in situ hybridization (FISH) for the presence of Hhe strains 1–4 as well as with a fifth probe that detected Helicobacter salomonis, Helicobacter bizzozeronii, or Helicobacter felis. A significant association of positive Warthin–Starry status with Hhe infection was found in cases of sick cats (22/29; p < 0.05 by Chi-square; χ2 = 7.034). Interestingly, a significant association between Hhe status and a diagnosis of lymphoblastic or lymphocytic lymphoma was observed as well in a subset of 24 Warthin–Starry positive lymphoma cases: of lymphoblastic lymphoma cases, 13/17 were positive for Hhe (p < 0.05; χ2 = 4.854). Hhe strains 2 and 4 were most commonly found (18/29 and 17/29, respectively) among sick cats, although a higher than expected number of cats was also positive for Hhe1, which initial reports have described as rare in cats and common in humans. The association found between a positive Hhe status with the presence of feline gastric lymphoma, especially lymphoblastic lymphoma, argues for the need to conduct prospective studies to better identify the frequency and strain distribution of Hhe infection in both healthy and clinically ill cats, particularly those cats with gastric lymphoma.  相似文献   

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