首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 31 毫秒
1.
The sensitivity of the abattoir inspection procedure introduced for Australian export beef in 1976 was compared to a detailed necropsy procedure for the detection of tuberculous lesions in cattle. In a sample of cattle that were reactors to the tuberculin test, abattoir inspection failed to detect an estimated 47% of cattle with lesions. The detailed necropsy examination of cattle with lesions of tuberculosis identified 21 sites of infection compared with 13 to 18 in cattle examined by routine meat inspection procedures. Of the lesions detected during detailed necropsy, 15.9% did not involve the thoracic cavity or the medial retropharyngeal lymph nodes. The failure to detect lesions during abattoir inspection has its greatest significance in an animal with a single lesion. If the 245 cattle found with single lesions during detailed necropsy had been examined by abattoir inspection using the 1976 or the 1986 procedures, 0.8 and 8.9%, respectively, of these animals would not have been detected because the diseased tissues would not have been examined. If meat inspection is to provide an effective means of monitoring the level of bovine tuberculosis during the final stages of eradication, a procedure no less sensitive than that introduced in 1976 should be used.  相似文献   

2.
Detailed postmortem examinations were conducted to evaluate the efficiency of meat inspection procedures and to determine the distribution of lesions in Mycobacterium bovis-infected cattle. The study involved routine inspection at slaughter, collection of tissues for detailed examination in the laboratory, and bacteriological examination to identify M. bovis. Additionally, a 10-year (1992--2001) meat inspection record was analysed to determine tuberculosis trends in the past decade. chi2-Test and simple regression were used to analyse the data. Out of 1350 cattle examined, 1.5% were found with tuberculous lesions. Routine abattoir inspection detected only 55% of cattle with confirmed lesions. Fifty-four per cent of tuberculous lesions were found in the lungs and thoracic lymph nodes, 23% in the lymph nodes of the head, and the remaining 23% in the mesenteric and other lymph nodes of the carcase. M. bovis was additionally isolated from an animal that had no gross lesions of tuberculosis. On average, the annual rate of whole-carcase condemnation due to generalized tuberculosis was 0.024% and it has increased annually by 0.34% over the past decade. The rate of whole-carcase condemnation indicates a high degree of TB transmission and requires immediate attention from both the economic and public health points of view. The lower sensitivity of routine abattoir inspection confirms the importance of improving necropsy procedures.  相似文献   

3.
Australia, a major exporter of meat, has met and continues to meet the import requirements of various countries. It is free of many epizootic and zoonotic diseases and is eradicating bovine brucellosis and tuberculosis. Frequently, individual country requirements have not been relevant to the animal and public health status in Australia. Such a situation is unscientific, wasteful and unnecessary, and may divert priorities away from areas of major public and animal health significance which should be the main concern of consumers both in Australia and overseas. In recent years the Inspection Service of the Department of Primary Industry has reviewed meat inspection procedures necessary to protect public and animal health in Australia and in countries importing Australian meat. Priorities include attention to national or regional occurrence of disease in Australia and to the use of scientific principles in inspection, including disease identification, concepts of pathogenesis and effectiveness in removal of diseased tissue from meat. Revised post-mortem procedures for cattle, pigs, sheep and goats more relevant to disease occurrence and consideration of public health are described. In particular, this involves a reduction in the number of lymph node incisions. Future directions for meat inspection in Australia are postulated. Concern is expressed that the requirements of some importing countries are fixed in their legislation and consequently might inhibit desirable developments. In this context it is important that scientifically sound national codes for meat inspection of the exporting country be accepted by importing countries as providing public and animal health safeguards.  相似文献   

4.
In spite of several quality control procedures used by Australia to ensure the wholesomeness of export meat, a number of pesticide residue violations were identified in the Australian product exported to the USA in May 1987. The pesticides involved were the organochlorines, dieldrin and heptachlor. The problems were caused by the persistence of organochlorines in soils and their illicit use or contamination of storage facilities. Animals grazing contaminated pasture, ingesting contaminated feed or held in contaminated yards over a period, bioaccumulated residues in their adipose tissues which eventually exceeded maximum residue limits (MRL) and caused violations. Though there was no immediate public health risk, the Australian Quarantine and Inspection Service (AQIS) of the Commonwealth Department of Primary Industries and Energy (DPIE), acted expeditiously to determine and eliminate the factors causing these problems, which threatened Australia's beef export industry worth in excess of two billion dollars annually. An overall strategic plan, "The Integrated Action Plan", was formulated and implemented by AQIS with the assistance of the relevant Departments of the States and the Northern Territory (NT), meat processing and export industries and livestock producer bodies. As a result of this action, the likely sources of contamination were identified and controlled. The National Residue Survey (NRS) was enhanced, a National Residue Data Base (NRDB) was established and a centralised computer system interactive with abattoirs, laboratories and animal health authorities developed. The cattle farm identity tail tag system already in place, capable of tracing cattle to the farm of origin was refined and trace back systems for sheep and pigs were utilised.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

5.
By studying carcass quality, expressed as affection, pathological findings, slaughter-weight and evaluation, a picture of an animal's health and potential as high quality food is achieved. This study compares the carcass quality in Swedish certified organic meat production with that of conventional meat production slaughtered during 1997. The study involves 3.9 million pigs, about 570,000 cattle and 190,000 sheep, all reared conventionally and 3483 pigs 4949 cattle and 4997 sheep reared according to organic standards. Pathological and additional findings are registered by meat inspectors from the Swedish National Food Administration at the post-mortem inspection. There was a significant difference at the post-mortem inspection of growing-fattening pigs; 28% of conventionally and 17% of the organically reared pigs had one or more registered lesion. The carcass evaluation of swine shows a higher meat percentage in conventional swine production. The total rate of registered abnormalities in cattle was systems around 28% from organic and 27% from conventionally reared herds. Carcass evaluation of cattle from organic herds gave higher classification in the EUROP system, whereas the fat content was lower than that of conventionally reared cattle. Sheep, reared both organically and conventionally, showed a lower rate of registered abnormalities than swine and cattle.  相似文献   

6.
Objectives Evaluate current disease surveillance activities at saleyards and abattoirs in New South Wales (NSW) in order to establish the prevalence of clinical anomalies in pigs at different sites and to compare the sensitivity of detecting anomalies inside versus outside of pens. Procedure Routine inspections of pigs by staff and government inspectors were observed at two saleyards and two abattoirs in NSW during three visits over a 2-month period (January 2008–March 2008). All pigs presented for sale or slaughter were examined for 19 clinical anomalies from either the side of the pen or while animals were moving outside the pen, with data being combined to give an assumed ‘gold standard’. We compared the prevalence of anomalies among animals at the four sites using logistic regression, as well as the sensitivity of detection of the two inspection methods. Results Frequency and methodology of routine inspection varied among sites. Of the 7747 pigs inspected, 822 (10.6%) showed at least one clinical anomaly. There was moderate agreement between detecting anomalies in penned pigs versus while being moved. Pigs at one abattoir exhibited significantly fewer anomalies than pigs at the other sites. Conclusion The prevalence of anomalies among pigs at saleyards and abattoirs in NSW was relatively high (≈10%). Weaknesses in current disease surveillance activities for pigs post-farmgate have been identified. Increased regulation, surveillance training and modification of standard operational procedures for inspection have the potential to improve the current system.  相似文献   

7.
Bovine tuberculosis (BTB) is a widespread and endemic disease of cattle in Ethiopia posing a significant threat to public health. Regular surveillance by skin test, bacteriology, and molecular methods is not feasible due to lack of resources. Thus, routine abattoir (RA) inspection will continue to play a key role for national surveillance. A cross-sectional study was conducted at Woldiya municipal abattoir from April 1, 2009 to April 5, 2010 to estimate the prevalence of BTB in slaughtered cattle on the basis of detailed abattoir inspection and to compare efficacy of RA inspection with respect to detailed abattoir inspection and isolation and identification of Mycobacterium. Diagnostic accuracies (with corresponding measures of statistical uncertainty) were determined by computing test property statistics (sensitivity and specificity). Agreement between RA and detailed abattoir inspections was measured using kappa statistics. Out of 1,029 slaughtered heads of cattle examined during the study period, 63 (6.12 %) and 15 (1.45 %) were diagnosed with gross tuberculous lesions by detailed abattoir meat inspections and RA meat inspections, respectively, making a prevalence of 6.12 % (95 % CI: 5.2–7.1) on the basis of detailed abattoir inspection. About 59.45 % of tuberculous lesions were observed in the lungs and associated lymph nodes, whereas 35.13 % lesions were from the lymph nodes of the head. From 63 cattle suspected with tuberculosis (TB) based on detailed abattoir meat inspection, nine (19.05 %) were identified as Mycobacterium bovis, while three (4.8 %) as Mycobacterium tuberculosis. The sensitivity of RA meat inspection was 23.8 % in comparison to the detailed abattoir meat inspection and 25 % in comparison to culture, respectively. Poor agreement (k?=?0.37) was seen between RA meat examination and detailed abattoir meat examination methods. Similarly, poor agreement (k?=?0.013) was seen between RA meat examination and culture results. In conclusion, relatively higher prevalence (6.12 %) was recorded in Woldiya municipal abattoir on the basis of detailed Abattoir inspection and RA meat inspection protocols currently utilized in Ethiopia which are insufficient to detect the majority (76.19 %) of TB lesions at the gross level, which indicates the magnitude of meat borne zoonotic TB as an ongoing risk to public health. Detailed abattoir inspection protocols were demonstrated to improve the detection level by approximately fourfold. In conclusion, routine meat inspections have limitations in detecting BTB-suggestive lesions which indicate the magnitude of meat-borne zoonotic TB as an ongoing risk to public health.  相似文献   

8.
Results of field studies which were performed in EU member states and which dealt with meat inspection procedures in fattening pigs were reviewed with respect to their contribution to alternative systems of meat inspection. The following was concluded: Inspection ante mortem (monitoring of circumstances at the farm of origin): Data which should be given to the notice of the authorities have not yet been satisfactorily defined and their informative value still is not yet clear The predictive character of information from the farm of origin regarding the health status of the animals (results of meat inspection) is not yet sound enough The technique of ante mortem inspection should be reconsidered also. Meat inspection (monitoring and assessment of lesions): In all studies the compared techniques (visual and official procedure) did not entirely find all lesions, which were supposed to be on the carcasses and organs. This was true in different percentages. The impact on consumer's health from the lesions monitored has to be discussed more thoroughly. The information presently available is not yet sound enough to generate a new practicable system of meat inspection. Further pilot studies are necessary.  相似文献   

9.
Skin lesions on pigs inflicted by humans compromise animal welfare and are the subject of increased public and political attention in Denmark. Systematic surveillance of such skin lesions was enforced in April 2010 at all Danish pig abattoirs, through the recording of meat inspection Code 904 for the presence of skin lesions suspected to be human inflicted. The objectives of the present study were to (a) estimate the apparent prevalence of Code 904s at the pig and herd owner level; (b) characterise the distribution of deliveries with pigs demonstrating a Code 904; (c) characterise the distribution of herd owners with repeated Code 904 recordings; and (d) determine the developments in Code 904 prevalence over time in Danish finishing pigs in the period from May 1, 2010 to September 30, 2013.  相似文献   

10.
OBJECTIVE: A field trial was conducted to evaluate the effectiveness of on-farm antemortem inspection performed by Australian pig producers in terms of proficiency in detecting unhealthy animals (suspects), the impact on food safety and animal welfare outcomes. ANIMALS: A total of 64 trial groups of market pigs (n= 10,703) were dispatched from 20 herds to three abattoirs in three states. PROCEDURE: All producers and abattoir antemortem inspectors were trained in antemortem inspection prior to the trial using a standardised set of antemortem criteria. Study 1 consisted of three comparisons: on-farm versus abattoir antemortem inspections on the same pigs, transport effects in suspect and normal pigs, and meat rejection and carcase disposition in suspect and normal pigs. Study 2 compared Salmonella spp status of suspect and normal pigs. Studies 3 and 4 were conducted to assist the interpretation of the results of on-farm versus abattoir inspection. Antemortem inspection results of three producers and one abattoir antemortem inspector were compared with those of a reference inspector (Gold Standard). RESULTS: Of the pigs examined, 2.12% (95% CI: 1.84%, 2.42%) were classified as suspect at on-farm antemortem inspection compared to only 0.14% at abattoir antemortem inspection. Forty one percent of pigs classified as suspect on-farm had locomotor problems (arthritis, lameness and foot abscess). Compared to normal pigs, suspect pigs had a relative risk of 67.7 (P < 0.0001) of suffering transport injuries. Meat rejection amounted to the equivalent of 9.68% of suspect carcases, compared to the equivalent of 0.35% of normal carcases. The isolation of Salmonella species from caecal content from 20.9% of 67 suspect pigs and 18.8% of 133 control pigs (two matched healthy pigs from the same batch for each suspect pig) were not significantly different. When compared with the reference inspector on-farm, three producers classified abnormalities in 2,495 pigs with high specificity (0.98), acceptable sensitivity (0.82) and kappa (0.57). CONCLUSIONS: With training, producer sensitivity in antemortem inspection may be high and more proficient than abattoir antemortem inspection. Use of producer inspections may have benefits for animal welfare and chain efficiency, but not food safety.  相似文献   

11.
A study aimed at describing the magnitude and distribution of gross lesions compatible with bovine tuberculosis (BTB) in Ethiiopian slaughter cattle in five abattoirs (four municipal and one export) located in various cattle husbandry systems in Ethiopia was carried out from July 2006 to January 2007 using detailed meat inspection procedure. Five representative abattoirs (four municipal and one export) located in distinct livestock management systems were selected. A total of 3322 cattle; 2876 (86.6%) male, 446 (13.4%) female; 3094 (93.1%) indigenous zebu, 140 (4.2%) crossbred and 88 (2.7%) pure exotic cattle were included in the study. A nine-year meat inspection record was also analyzed to elucidate the trend of BTB in the local cattle population.Of the carcasses inspected, 337 (10.2%, 95%CI= [9.2–11.2]) had lesions suggestive of tuberculosis, 69 (20.5%) generalized and 268 (79.5%) localized.TB prevalence showed a marked variation between categories of age, breed, class of animals, abattoir, geographic origin and husbandry system. It was higher in old and young animals than middle age group; in exotic than local breed; in calves than other classes of animals. The highest and lowest prevalence of TB was recorded in Adama (24.7%, 95%CI= [21.1–28.7]) and Yabello abattoirs (4.2%, 95%CI= [2.6–6.6]), respectively. Cattle whose origin was from Addis Ababa and its surrounding areas had higher prevalence of TB infection (23.9%, 95%CI= [17.6–31.5]).Cattle maintained in dairy farms had high degree of exposure (23.9%, 95%CI= [16.7–32.9]) to the infection than those maintained in other types of management system. Analysis of meat inspection records also revealed an increasing incidence of TB over the years. Our study demonstrated a high prevalence of tuberculosis in Ethiopian slaughter cattle and this could infer to similar scenario in a reference cattle population in the country. In view of Ethiopia’s increasing involvement in livestock export trade, the reported high prevalence of tuberculosis could be a major obstacle, particularly at this moment when sanitary requirements from importing countries are so much strict. Furthermore, the growing concern over increasing incidence of tuberculosis/HIV/AIDS co-infection, the high incidence of extra- pulmonary tuberculosis and a high risk of acquiring zoonotic tuberculosis among the majority of the population emphasize the need for paying the necessary attention towards the control of bovine tuberculosis.  相似文献   

12.
Mycobacteria were isolated from 195 of 200 lesions in lymph nodes identified as granulomatous by meat inspectors at 4 abattoirs in South Dakota. Mycobacterium avium serotypes 1 and 2 accounted for 89% of the isolants. Mycobacteria were isolated more frequently from lesions than acid-fast bacilli were observed on microscopic examination (P less than 0.001). The frequency with which mycobacteria was isolated was similar to the occurrence of granulomatous lesions. The numbers of the various kinds of mycobacteria isolated at each of the 4 abattoirs and for the 3 meat inspection disposition classes were not significantly different.  相似文献   

13.
An outbreak of tuberculosis in pigs and cattle caused by Mycobacterium africanum produced lesions in the pigs similar to those caused by M tuberculosis, M bovis and M avium, with caseation in the lymph nodes of the head and in the jejunal lymph nodes. Bacteriological examination of the dysgonic mycobacteria isolated showed that they were M africanum I. The intradermal tuberculin test was very reliable in pigs, differentiating between mammalian and avian reactions, and the results of the test were in accordance with the lesions found at meat inspection. No clinical signs were observed during the outbreak, and the infection was neither serious nor progressive. There were no lesions in the tuberculin-positive cattle. The source of the infection remains unknown.  相似文献   

14.
OBJECTIVE: A field trial was conducted to evaluate the effectiveness of on-farm antemortem inspection performed by Australian pig producers in terms of proficiency in detecting unhealthy animals (suspects), the impact on food safety and animal welfare outcomes. ANIMALS: A total of 64 trial groups of market pigs (n = 10,703) were dispatched from 20 herds to three abattoirs in three states. PROCEDURE: All producers and abattoir antemortem inspectors were trained in antemortem inspection prior to the trial, using a standardised set of antemortem criteria. Study 1 consisted of three comparisons: on-farm versus abattoir antemortem inspections on the same pigs, transport effects in suspect and normal pigs, and meat rejection and carcase disposition in suspect and normal pigs. Study 2 compared Salmonella spp. status of suspect and normal pigs. Studies 3 and 4 were conducted to assist the interpretation of the results of on-farm versus abattoir inspection. Antemortem inspection results of three producers and one abattoir antemortem inspector were compared with those of a reference inspector (Gold Standard). RESULTS: Of the pigs examined, 2.12% (95% CI: [1.84%, 2.42%]) were classified as suspect at on-farm antemortem inspection compared to only 0.14% at abattoir antemortem inspection. Forty one percent of pigs classified as suspect on-farm had locomotor problems (arthritis, lameness and foot abscess). Compared to normal pigs, suspect pigs had a relative risk of 67.7 (P < 0.0001) of suffering transport injuries. Meat rejection amounted to the equivalent of 9.68% of suspect carcases, compared to the equivalent of 0.35% of normal carcases. The isolation of Salmonella species from caecal content from 20.9% of 67 suspect pigs and 18.8% of 133 control pigs (two matched healthy pigs from the same batch for each suspect pig) were not significantly different. When compared with the reference inspector on-farm, three producers classified abnormalities in 2495 pigs with high specificity (0.98), acceptable sensitivity (0.82) and kappa (0.57). CONCLUSIONS: With training, producer sensitivity in antemortem inspection may be high and more proficient than abattoir antemortem inspection. Use of producer inspections may have benefits for animal welfare and chain efficiency, but not food safety.  相似文献   

15.
Bovine tuberculosis (bTB) is a zoonotic, infectious, chronic and contagious disease, caused by Mycobacterium bovis that mainly affects cattle. This pathology has a negative impact on animals and animal products trade. Unfortunately, in Burkina Faso where agriculture and livestock sectors represent around 80% of the socio-economic activities, the real situation of the disease is not well known especially in small ruminants and swine. Thus, our study focused on both the epidemiology and the microbiological diagnosis of tuberculosis (TB) in small ruminants and pigs slaughtered at Bobo-Dioulasso abattoir. A prospective study was conducted between August 2017 and December 2017. Epidemiological data collection was performed during routine meat inspection; moreover, samples were taken and transported to the Bacteriology laboratory of Centre Muraz for microbiological analyses. This diagnosis consisted in search of Acid Fast Bacilli (AFB) using the hot Ziehl–Neelsen staining. Out of a total of 14 648 small ruminants and 2430 pigs slaughtered during the study period, 156 and 17 had lesions suggestive of bTB with prevalence of 1.07% and 0.7%, respectively. Females and those between 2 and 4 years old were mainly infected. The most affected organs were: lungs, liver, spleen and lymph nodes. Finally, microscopy revealed 43.35% (75/173) of positive cases for AFB. These results confirm the presence of bTB in small ruminants and pigs in Burkina Faso. Efforts must still be made in the fight against this zoonosis in order to limit its economic and public health impacts.  相似文献   

16.
Cattle transported to the government-run cattle market and slaughter slab in Akinyele, Oyo State, Nigeria on their final voyage are facing a disturbingly cruel, filthy and unsafe environment that is also raising the risk of contamination of meat sold for human consumption. This report gives a picture of what the cattle have to go through before they are slaughtered. This study also reveals cattle awaiting slaughter in abysmal health conditions, cows pulled with extreme force towards lairage and slaughter slab. Equally disturbing is the filthy situation inside the abattoir where the risk of contamination of meat is significant. Also, poor meat handling, transportation and sales practices subject meat to contamination leading to poor quality and exposure of human consumers to health risk. Development of hygienic slaughter slab operations, improved transportation system for both livestock and meat is therefore recommended; not only for Akinyele, but all abattoirs and slaughter slabs in Nigeria.  相似文献   

17.
A study to determine the presence and prevalence of bovine tuberculosis in slaughter cattle in Kenya was carried out in two abattoirs from July to November 2009. Routine postmortem meat inspection was performed on a subpopulation of 929 cattle selected randomly from among 4,984. Carcases were inspected for gross tuberculous lesions which were then examined for acid-fast bacilli, (AFB), cultured for isolation of mycobacteria and the isolates characterised by DNA molecular analysis. Of the carcases examined, 176 (18.95?%, 95?% CI) had lesions suggestive of tuberculosis. AFB were observed in 63/176 of the lesioned cattle and mycobacteria were isolated from 64 of them. The isolates were identified as Mycobacterium bovis (19/64), Mycobacterium tuberculosis, (2/64) and mycobacteria other than tuberculosis (43/64). The prevalence of M. bovis by molecular analysis was 2.05?% (95?% CI). This study documents for the first time the presence of bovine tuberculosis among slaughter cattle in Kenya. There is therefore a need to formulate and implement control programmes in order to minimise transmission among animals and to humans. Isolation of M. tuberculosis from cattle underscores the risk tuberculous humans pose to animals.  相似文献   

18.
OBJECTIVE: To evaluate organoleptic postmortem inspection techniques for bovine livers and kidneys. STUDY DESIGN: At Australian export abattoirs, bovine liver and kidneys are assessed and graded by qualified meat inspectors during normal operations. Over a 12-month period at a large abattoir in eastern Australia during 1997 and 1998, a sample of these organs was reassessed independently using a range of pathological and microbiological methods. Agreement between routine inspection and independent assessment was evaluated using methods of inter-rater agreement. RESULTS: A total of 944 livers and 1374 kidneys were included in the study. All of these organs had been classified during routine inspection. The authors examined 363 livers and 329 kidneys both grossly and histologically, including 36 livers and 14 kidneys that were also subjected to microbiological examination. All other organs were only examined grossly. There was only a moderate level of agreement between the routine and independent assessment methods. For livers, the percentage agreement was 80.2%, McNemar's test of symmetry 55.2 (3 degrees of freedom, P < 0.001) and kappa 0.63. For kidneys, the percentage agreement was 67.8%, McNemar's test of symmetry 9.9 (1 df, P = 0.002) and kappa 0.35. CONCLUSIONS: The results reinforce concerns from a number of authors about organoleptic postmortem inspection. Risk assessment methodologies offer the opportunity to modify inspection techniques in a manner that is most relevant to current public health concerns.  相似文献   

19.
Objective To evaluate organoleptic postmortem inspection techniques for bovine livers and kidneys.
Study design At Australian export abattoirs, bovine liver and kidneys are assessed and graded by qualified meat inspectors during normal operations. Over a 12-month period at a large abattoir in eastern Australia during 1997 and 1998, a sample of these organs was reassessed independently using a range of pathological and microbiological methods. Agreement between routine inspection and independent assessment was evaluated using methods of inter-rater agreement.
Results A total of 944 livers and 1374 kidneys were included in the study. All of these organs had been classified during routine inspection. The authors examined 363 livers and 329 kidneys both grossly and histologically, including 36 livers and 14 kidneys that were also subjected to microbiological examination. All other organs were only examined grossly. There was only a moderate level of agreement between the routine and independent assessment methods. For livers, the percentage agreement was 80.2%, McNemar's test of symmetry 55.2 (3 degrees of freedom, P < 0.001) and kappa 0.63. For kidneys, the percentage agreement was 67.8%, McNemar's test of symmetry 9.9 (1df, P = 0.002) and kappa 0.35.
Conclusions The results reinforce concerns from a number of authors about organoleptic postmortem inspection. Risk assessment methodologies offer the opportunity to modify inspection techniques in a manner that is most relevant to current public health concerns.  相似文献   

20.
A revised inspection system for fattening pigs in the EU has been proposed emphasizing the need for a more detailed documentation of the fattening process. It is supposed that the availability of such information enables a discrimination of conspicuous and non-conspicuous lots of fattening pigs delivered to the abattoir allowing for a modified, only visual inspection of non-conspicuous lots. This proposal motivated a study performed in 1996 on about 22,000 pigs, searching, among other things, for first hints on associations between management/farm conditions for fattening pigs and lesions found at meat inspection, which can be used for discrimination. Taking the two lesions 'pneumonia' and 'callous affections of the legs' as examples this contribution demonstrates the use of regression trees to visualize association structures and to develop hypotheses on relations between lesions and farm characteristics. An association of 'callous affections of the legs' with flooring systems is clearly shown in the generated tree. The occurrence of 'pneumonia' seems to be associated with the application of disinfection measures in this data set. However, this result should be interpreted with caution as some problems for data analysis arise because of the low number of farms in this study in relation to the high number and complexity of farm characteristics considered. A further problem is the high variability of daily deliveries within farms that cannot be explained referring to farm characteristics common to all deliveries. As a conclusion data from this study have been useful to develop hypotheses on associations between farm characteristics and lesions at meat inspection. However, there is need for further, more specific studies before such associations can be utilized to discriminate between conspicuous and non-conspicuous lots of fattening pigs.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号