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1.
Production, morbidity, mortality and culling were investigated on seven commercial red veal farms in Ontario. The total number of calves included in the study group was 2251. The mean exit weight of marketed calves was 291 kg, with an average daily gain of 1.52 kg/day over the entire production period. The percentage of calves receiving one or more treatment days was 55%, with an average number of individual treatment days per treated calf of 3.9. An increasing number of treatment days, particularly up to eight days of treatment, was associated with decreasing average daily gain, and an increased probability of being lost from production due to death or culling. The percentage of calves which died during production was 5.4, with 0.8% of calves culled.  相似文献   

2.
Livestock-associated methicillin-resistant Staphylococcus aureus (LA-MRSA) is highly prevalent in pork and veal production chains. In this study, we used data from a cross-sectional survey on 2151 calves from 102 veal calf farms to identify potential risk factors, with the goal of reducing MRSA prevalence by developing intervention strategies. Overall, calves from rose veal farms had a lower risk of LA-MRSA carriage than calves from white veal farms. Data were analysed separately for white and rose veal calves, because management systems of the two production chains were largely different. Group treatment with antimicrobials appeared to be a risk factor for MRSA carriage in white veal calves in univariate analyses, but was not included in the final multiple regression model that included age of the calves and rodent control. Number of start treatment days was positively associated with LA-MRSA carriage in rose veal calves, and was the only risk factor selected for the final multiple regression model for this group. Interpretation of the results from this cross-sectional study is complicated by the strong correlation between antimicrobial use, LA-MRSA carriage and age of the calves. Other age-related factors may be more influential. However, taken together these findings emphasize the need for prudent use of antimicrobials, and point to improvement of farm hygiene as a control measure.  相似文献   

3.
A case-control study of diarrheal disease in veal calves was conducted over a three month period on a single large veal farm in southern Ontario. One hundred diarrheic calves (cases) were identified by visual examination of their feces. Each case was matched to two nondiarrhetic controls from the same room on the same day, and a fecal sample was obtained from each animal. Fecal consistency of cases and controls was observed daily for one week following sample collection. Control calves which developed diarrhea during that period were excluded from the study. Breed, sex and the date and nature of antimicrobial drugs administered to each calf were recorded. Moisture content of fecal samples was measured by weighing samples before and after oven drying. Samples were screened for verocytotoxigenic Escherichia coli (VTEC) using a Vero cell assay, for enterotoxigenic E. coli (ETEC) using an immunoblot procedure with anti-K99 monoclonal antibodies, and for Salmonella species using modified semi-solid Rappaport-Vassiliadis medium. A latex agglutination test was used to detect rotaviruses, and samples were examined for cryptosporidia using sucrose wet mounts. No VTEC were identified in cases or controls. One calf was positive for Salmonella and three were positive for ETEC. Rotaviruses were detected in four cases and four controls. A significant positive association was found between diarrhea and infection with Cryptosporidium. This study thus provided no evidence of an association between diarrhea and infection with either VTEC, ETEC, Salmonella spp. or rotaviruses in the population examined. On the other hand our results do suggest that Cryptosporidium infection may promote transient diarrheal disease in veal calves in Ontario.  相似文献   

4.
Data on calf mortality, calving site, calf-rearing facilities, and calf-management procedures were collected from 16 dairy farms in Tulare County, California. Discriminant analyses were used to test if any significant differences in these factors existed between farms with higher than average and farms with lower than average death losses. The average mortality rate over a period of at least 2 years on individual farms varied from a low of 3.5 +/- 1.1% to a high of 30.6 +/- 3.1%. Calf management personnel was the only factor significantly related to the mortality rate, with considerably fewer death losses on farms where the owner managed the calves than on farms where employees performed these duties. In general, other factor categories relating to size of the cow herd, calving site, and calf housing were not related significantly to calf deaths. The average number of heifer calves born each year on individual farms was increasing year by year, and on some farms, there seemed to be a concomitant increase in death losses. This, together with the tendency toward greater number of deaths on the larger owner-managed farms, indicated that calf care was diluted under these conditions.  相似文献   

5.
Two field efficacy studies, involving a total of 92 naturally infected, pneumonic veal calves, were conducted to compare the efficacy of the β-lactamase inhibitor sulbactam plus ampicillin to ampicillin alone in the treatment of bacterial pneumonia. Cultures from nasal swabs and lung tissue during the 10 or 11 day studies were predominantly ampicillin-resistant Pasteurella multocida. Ampicillin (6.6 mg/kg) or sulbactam-ampicillin (3.3 mg/kg sulbactam + 6.6 mg/kg ampicillin) was injected intramuscularly once daily for either three days or six days. Sulbactam-ampicillin administered once daily for three or six days resulted in lower (P≤0.05) average body temperature with a concomitant clinical improvement (P≤0.05), and produced numerical advantages and/or statistical improvements over ampicillin in mortality, weight gain, and overall response of calves to treatment. The combined mortality for the two studies in the ampicillin and sulbactam-ampicillin treated groups was 43% and 14%, respectively. We concluded that sulbactam-ampicillin was superior to ampicillin in the treatment of ampicillin-resistant bacterial pneumonia in veal calves.  相似文献   

6.
Calf losses (CL, mortality and unwanted early slaughter) in veal production are of great economic importance and an indicator of welfare. The objective of the present study was to evaluate CL and the causes of death on farms with a specific animal welfare standard (SAW) which exceeds the Swiss statutory regulations. Risk factors for CL were identified based on information about management, housing, feeding, and medication. In total, 74 production cohorts (2783 calves) of 15 farms were investigated. CL was 3.6%, the main causes of death were digestive disorders (52%), followed by respiratory diseases (28%). Factors significantly associated with an increased risk for CL were a higher number of individual daily doses of antibiotics (DDA), insufficient wind deflection in winter, and male gender. For administration of antibiotics to all calves of the cohort, a DDA of 14-21 was associated with a decreased risk for CL compared to a DDA of 7-13 days.  相似文献   

7.
Sixteen dairy farm owners in Tulare County, California, provided data on heifer calf births and deaths. Eleven of these dairymen had maintained records on the calves before this study was done, and 5 agreed to maintain them for 6 months. Basic statistical techniques, including time series analyses and life-table methods, were used to examine the data for temporal and demographic characteristics. Overall, the calf mortality rate on the 16 farms averaged 17.3 to 20.2%. The interfarm variation in mortality rate was large, ranging from 3.7 to 32.1%. Time series studies indicated that the extent of death losses increased during midsummer (June, July, August) and midwinter (November, December, January), with mortality rates in winter months being 20% greater than those in summer. Death losses in October and March were highly variable; however, losses in October usually exceeded the yearly average; those in March did not. Also, 80% of the dairymen recorded the same relative change in mortality rate during each of 2 consecutive winters and 2 consecutive summers. The risk of death for calves was greatest in their 1st week of life on most of the farms; of all deaths in calves less than 5 weeks old, 55% occurred during the 1st week of life, and 27% occurred during the 2nd. In general, the death loss in calves between 5 weeks and 3 months old was less than 2%.  相似文献   

8.
The objective of this study was to document mortality reasons and risk factors for mortality in dairy calves in the northeast of Iran. This was a prospective cohort study of calves born on ten commercial dairy herds from 21 March 2009 to 20 March 2010. A total of 4097 live calves were followed for 90 days after birth. For each calf details of sex, parity of the dam, type of parturition and season of birth were recorded. The interval (in days) from the date of birth to the date of death and the reason for death was recorded for those calves that died before 90 days of age. A Cox proportional hazards model, including a frailty term to account for unmeasured herd-level effects was developed to quantify the effect of factors associated with time to death. Two hundred and sixty-six (6.5%, 95% CI: 5.8-7.3%) of the 4097 live-born calves died or were euthanised before 90 days of age. The most important reasons for death were digestive tract disorders (58% of all deaths, 95% CI: 52-64%) followed by respiratory diseases (13% of all deaths, 95% CI: 9-17%). Calves exposed to dystocia at birth had 2.09 (95% CI: 1.49-2.92) times the daily hazard of death compared with calves born from a normal calving. The daily hazard of death for calves born in the summer was 1.93 (95% CI: 1.41-2.64) times greater than the hazard for those calves born in the autumn. Inclusion of the herd-level frailty term had a significant effect on hazard estimates indicating that the study herds were heterogeneous in the distribution of unmeasured herd-level factors influencing calf survival. Our results show that diarrhoea is the most important cause of calf mortality in dairy herds in this area of Iran and that environmental and management factors affect calf mortality rate.  相似文献   

9.
欧盟犊牛福利养殖措施及其效果分析   总被引：1，自引：0，他引：1  
小白牛肉为高档肉品,深受欧美一些国家消费者青睐。本文介绍了在小白牛肉生产中,传统的犊牛养殖方式在动物福利方面的弊端,欧盟国家为保障犊牛的基本福利采取的措施及取得的成效。对于有效利用我国丰富的小公犊牛资源,发展小白牛肉产业具有一定的参考价值。  相似文献   

10.
Olsson, S.-O., S. Viring, U. Emanuelson and S.-O. Jacobsson: Calf diseases and mortality in Swedish dairy herds. Acta vet. Scand. 1993,34, 263-269.– A survey of the mortality and morbidity affecting calves during the first 3 months of life was carried out. Results are reported from 131 herds with altogether 5,050 calvings. These herds kept individual calf cards for all calves born. The incidences of abortions and stillborn calves were 0.6% and 3.6%, respectively. During the period 0-90 days the mortality and morbidity were 2.6% and 11.0%, respectively. The frequencies of enteritis and pneumonia in calves were 7.2% and 0.8%. Mortality and morbidity were influenced by breed, season, age of the dam and time of first colostrum. The frequencies of abortions, stillborn calves, mortality and morbidity varied considerably between herds. Herd factors influencing mortality and morbidity during different periods of time were: herd size, yield, zero-grazing, whether the calf was allowed to feed by suckling, the design of the calf pens, and previous incidence of infectious enteritis in the herd. On average, both mortality and morbidity in calves were low, though in certain herds, temporarily high frequencies were registered.  相似文献   

11.
An episode of zinc toxicosis in 95 veal calves caused $29,602 in losses to the producer ($315/affected calf), most of them direct, out-of-pocket losses. Increased calf mortality and increased veterinary service costs accounted for a majority (70%) of the losses. Reduction of losses may have been accomplished by removing the source and increasing the roughage content in the diet, or by shipping the animals for immediate slaughter. Given the magnitude of the financial loss, especially those associated with calf mortality, it was concluded that producers should refrain from using large amounts of mineral supplements unless a deficiency has been diagnosed.  相似文献   

12.
Forty-five calves on four veal calf units were monitored during the first four weeks after their arrival. Faecal samples were collected on alternate days and screened for the presence of rotaviruses, bovine coronavirus, Cryptosporidium oocysts, K99 positive strains of E. coli and Salmonella spp. Rotaviruses and Cryptosporidium were the most commonly detected agents (78% and 60% respectively of the calves). Bovine coronavirus was detected in the faeces of 18% of the calves, whilst K99 positive E. coli was only found in 2 samples from one calf. Salmonella spp. were not isolated from any of the 646 faecal samples examined. Shedding of rotaviruses occurred in a bimodal pattern beginning in the first week of the survey. Cryptosporidium oocysts were detected most frequently in the interval between the two peaks of rotavirus shedding. The presence of rotaviruses or Cryptosporidium oocysts in faeces was not strongly associated with scour, nor were combined infections with these agents or the cases of bovine coronavirus infection. The condition of the calves throughout the survey was generally satisfactory.  相似文献   

13.
On a yearly basis, large calf ranches rear thousands of neonatal cattle for replacement heifers, veal or dairy beef. Dairy beef ranches obtain bull-calves from multiple sources and with questionable colostrum intake histories. Such ranches accumulate large amounts of data that could be used to help them with calf purchasing and on-farm management practices to avoid losses. Our purpose was to describe some calf purchase factors associated with mortality in neonatal calves raised on a single large calf ranch. Computerized records describing 120,197 bull-calves purchased between January 1997 and November 1998 were used in a survival analysis. Risk factors for mortality within the first 4 weeks after arrival on the ranch included body weight on arrival, month of arrival, and the calf supplier. The strength of the effects was conditional on the week after arrival to the ranch.  相似文献   

14.
6头中国西门塔尔杂交二代公犊用于小牛肉生产试验。结果显示：经223d育肥,试验末期平均体重达到了221.58kg,日增重0.578kg,每头牛可获利365.36元。说明利用中国西门塔尔二代杂交牛和饲草料资源开展小牛肉生产在高原地区,能获得较好的经济效益。每头中国西门塔尔杂交育肥牛可获得18.07kg的高档牛肉,高档肉块重量占到活重的8.90%;优质牛肉22.95kg,优质肉块重量占到活重的11.31%。从牛肉产量上证明中国西门塔尔二代杂交牛可以作为高原地区生产高档优质牛肉的肉用牛种。  相似文献   

15.
OBJECTIVE: To compare health performance during the first 28 days in the feedlot for vaccinated or conditioned feeder calves sold through special auctions in Ontario with health performance for calves sold through conventional auctions in the province. DESIGN: Cohort study. ANIMALS: 12,313 calves sold through conventional and special auctions at the Keady Livestock Market during the fall of 1999 and 2000. PROCEDURE: Buyers of calf groups were approached at the auction market or contacted by telephone and asked to record the number of calves requiring treatment for bovine respiratory tract disease (BRD) during the first 28 days after purchase. RESULTS: 211 calf groups (> or = 20 calves/group) were followed up for 28 days after purchase. Multivariate logistic analysis indicated that vaccinated calves purchased through special auctions were 0.68 (95% confidence interval, 0.50 to 0.93) times as likely to receive treatment for BRD as were calves purchased at conventional auctions and that conditioned calves were 0.22 (95% confidence interval, 0.12 to 0.38) times as likely to receive treatment. Groups that received antimicrobials by injection on arrival at the feedlot were 0.64 (95% confidence interval, 0.43 to 0.96) times as likely to be treated as were groups that did not. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that vaccinated and conditioned calves were less likely to receive treatment for BRD during the first 28 days in the feedlot; however, there was no difference in mortality rate.  相似文献   

16.
A prospective study was carried out on 845 heifer calves born during 1991 on 30 Holstein dairy farms in southeast Minnesota. The objectives of the study were to describe the epidemiology of morbidity and mortality in dairy calves from birth to 16 weeks of age (with an emphasis on respiratory disease), to examine individual calf and herd management practices as risk factors for calf morbidity and mortality, and to validate producer diagnosis of mortality. Incidence rates for all morbidity, enteritis, and pneumonia were 0.20, 0.15, and 0.10 cases per 100 calf-days at risk for the period of the study. Risk of enteritis was highest in the first 3 weeks of life, with pneumonia risk highest at 10 weeks of age. Case fatality rates averaged 11.8%, 17.9%, and 9.4% for all diagnoses, enteritis, and pneumonia, respectively. Average daily rates of gain from birth to 16 weeks of age differed between farms that had inadequate calf housing (0.8 kg day−1) versus those with adequate calf housing (1.0 kg day−1). Approximately half of the calves in the cohort (418) had blood samples taken monthly from birth until 16 weeks of age. Of the calves sampled, only 19 calves showed a four-fold rise in serum titers to respiratory viruses. Sixteen calves seroconverted to BVDV, two calves to IBRV, and one calf to PI3 virus. Of 98 calves less than 10 days of age tested for adequacy of passive transfer, 35 (35.7%) had serum immunoglobulin levels of less than 800 mg dl−1. There were no significant differences in mortality or morbidity between calves that had adequate passive transfer and those that did not. The incidence of mortality was 0.08 deaths per 100 calf-days at risk; 64 calves died during the 16 months of the study. The risk of death was highest at 2 weeks of age. Enteritis was the most common cause of death (28 deaths, 44% of all deaths) followed by pneumonia (19 deaths, 30% of all deaths). Comparing producer diagnosis of mortality with necropsy results yielded sensitivities of 58.3% and 56% and specificities of 93% and 100% for producer diagnoses of enteritis and pneumonia, respectively. The kappa statistic comparing producer diagnosis with necropsy result was 0.47. The most common pathogens isolated from calves that died of enteritis were rotavirus (five calves), and Escherichia coli (four calves). Pathogens isolated from pneumonic lungs included Pasteurella multocida (three calves), Haemophilus somnus (three calves), and Pasteurella haemolytica (one calf).  相似文献   

17.
We studied the importance of the stockperson's behavior on veal calf behavior using 22 veal calves housed in individual crates. Eleven calves received minimal contact from the stockperson, and the other 11 calves were stroked and allowed to suck the stockperson's fingers after each meal during the entire fattening period (21 wk). The effects of this additional contact with the stockperson on the calves' responses to people was studied, when in their home environment (crate) or outside their home environment (singly in a novel arena). When tested in their home environment, the calves receiving additional contact withdrew less from the approach of humans (familiar or unfamiliar) (P < .05) compared with control calves. When tested outside the home environment with a human (familiar or unfamiliar) standing motionless, calves that had received additional contact interacted more frequently and for a longer time with the humans and defecated less often compared with control calves (P < .05). In conclusion, being stroked and sucking the stockperson's fingers seemed to be experienced as positive by the calf, because they reduced withdrawal from and increased approaches to familiar and unfamiliar humans in familiar and unfamiliar environments. Such a lower reactivity to people could improve ease of handling, animal performance, and animal welfare.  相似文献   

18.
Ninety-five 3- to 6-month old male Holstein veal calves were evaluated after an episode of zinc toxicosis, to describe clinical signs and to identify management and/or host-related factors that may have contributed to death. Clinical signs appeared 23 days after feeding of milk replacer commenced. Of 85 calves examined, 64 had pneumonia (75.5%), 62 had ocular signs (72.9%), 46 had diarrhea (54.1%), 34 were anorectic (40.0%), 15 were bloated (17.6%), 8 had cardiac arrhythmias (9.4%), 3 had convulsions (3.5%), and 3 were polydipsic/polyphagic (3.5%). Clinical signs began to appear when calves each were being fed approximately 1.5 to 2.0 g of zinc/day and exposed to a cumulative zinc intake of 42 to 70 g, from a milk replacer containing 706 micrograms of elemental zinc/g of milk replacer. Of 95 calves studied, 1 died before zinc was supplemented, 16 died during the episode, 12 were euthanatized, 1 was lost to follow-up evaluation, 1 was culled, and 64 were slaughtered. Deaths attributable to zinc toxicosis were observed between 25 and 53 days after the milk replacer was supplemented with zinc. Calves died while being exposed cumulatively to 30 to 66 g of zinc. The factors of previous pneumonia severity, age, cumulative daily exposure to zinc, and calf location within a bay were examined for possible associations with mortality, using stepwise logistic regression. Though younger calves tended to have a higher mortality than older calves, neither age category nor severity of pneumonia, before zinc supplementation, accounted for a significant mortality.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

19.
In this 90-day study, 60 male Holstein dairy calves were experimentally infected with Giardia duodenalis. Calves were randomly blocked by weight into treatment (N=30) and placebo (N=30) groups. Beginning on study Day 0, calves in the treatment group were administered an oral dose of 5mg/kg of fenbendazole once daily for three consecutive days. Calves in the placebo group received a daily oral treatment of 5 ml of saline for 3 days. These treatments were repeated on Days 30 and 60 of the study. Fecal samples were collected from calves once per week and examined for the presence of Giardia cysts. Calves were monitored daily for clinical signs of intestinal disease and all episodes of diarrhea recorded. Calves were weighed once per week and total feed intake, on a dry matter basis, was calculated daily. Following each treatment, the number of calves shedding Giardia cysts in the fenbendazole group was reduced (p<0.001) compared to the saline group. Also, calves in the fenbendazole group had fewer cysts (p<0.05) detected in their feces following treatment compared with calves that received saline. Within 2 weeks post treatment, the number of infected animals and fecal Giardia cysts returned to placebo levels. This pattern of reinfection was consistent after every treatment period. Calves receiving fenbendazole had fewer total days with diarrhea (p<0.01) and the average number of days each calf had diarrhea was reduced (p<0.05), compared to the placebo group. There were no differences in mean body weight, average daily gain, or feed intake between the treatment or placebo groups. This study demonstrates that fenbendazole is an effective treatment for giardiosis, resulting in a clinical benefit and reducing the number of infective cysts shed by calves. However, this treatment regime had no impact on production parameters and reinfection occurred rapidly in these calves.  相似文献   

20.
A mail survey of feedlot owners was conducted to evaluate the efficacy of prophylactic antimicrobials, given in the water, or in the ration at preventing illness and/or death. One hundred and twenty-seven farmers from southwestern Ontario collaborated in the study. The percentage of calves requiring individual antimicrobial treatment, for any reason within 28 days of arrival was 22.6% (median 17.8%) and 0.6% (median 0.2%) died in that period. The use of medicated starter rations was not associated with either treatment or mortality rates until the effects of a number of other variables were controlled, analytically. Thereafter, the use of medicated feed was associated with a decrease in mortality rate, but was unrelated to morbidity rate. Overall, the use of medicated water was not associated with treatment or mortality rates. The use of sulphonamides was associated with decreased morbidity, but increased mortality rates. After controlling, analytically using multiple regression, the effects of other variables, the use of medicated water was associated with a significant increase in mortality rates. The other major factors which influenced mortality rates were the number of calves per group, the number of subgroups of calves in each group and whether the group contained cattle from different sources; all were related to increased mortality rates. During a two year period, more feedlot owners appeared to be using medicated rations as opposed to medicated water, as a means of providing antimicrobials to their newly arrived calves.  相似文献   

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