A study of preslaughter pig handling and stunning in selected South African Highveld Region abattoirs.

The study hypothesis was that pre-slaughter handling is not conducted in such a way that pigs can be considered humanely slaughtered, nor is it conducive to promoting those properties of fresh meat that could enhance pork quality. The 1st phase of the investigation was aimed at confirming the present compliance level within the prescribed norms. To this end the importance of stunning induction requirements for effective electrical stunning, the welfare implications relating to the pre-slaughter handling of pigs and the stunning and sticking techniques were investigated. Pre-slaughter welfare of the pigs at the abattoir was found to be influenced at the outset by the origin and type of pig slaughtered, the daily throughput range of pigs and the type of abattoir involved. A disappointing pre-arrival aspect was that deficiencies in road motor vehicles were observed while off-loading pigs. Through poor design or lack of maintenance, another factor that hampered free movement of pigs was the off-loading facilities. The nature of animal behaviour in the pens, in the passages and when going into the stunning area was directly related to the pig handling efficiency and to the nature and extent of design and maintenance problems with equipment. None of the abattoirs had a well designed in-feed to a well planned stunning area/facility, and a very high level of pig pre-slaughter stress prevailed. The optimum position of the electrodes is virtually impossible to attain under practical conditions and the practice of repeat application of electrical stunning is common. Of the total sample size (n = 1175), 34% were difficult to shackle, 90% of these being from the abattoirs tending to slaughter more routinely a wide range of different sized pigs. In this survey 149 pigs (13%) required more than a single sticking attempt to bleed out properly, considerably higher than in other published reports.

Neurocysticercosis: a possible cause of epileptiform seizures in people residing in villages served by the Bethanie clinic in the North West Province of South Africa.

A study to detect human taeniasis and cysticercosis was conducted in 4 village communities served by the Bethanie clinic in the North West Province, based on reports of people being diagnosed there with epileptiform episodes. Many home owners in the villages rear pigs in small numbers for both meat availability and an immediate income from live pig or pig meat sales. The primary aim of the work was to conduct in the study area a census of all small scale pig producers and a survey of rural village consumers, both by means of a structured questionnaire. The former reviewed pig husbandry practices, slaughter and marketing of pigs and the latter provided information on pork consumption, sanitation as well as people's basic knowledge of Taenia solium. Stool samples from consenting participants were screened by a contracted approved laboratory for IR solium. A descriptive analysis of retrospective data was conducted at the Bethanie clinic to determine the proportional morbidity of neurocysticercosis from the medical records of patients diagnosed with seizures in an attempt to establish possible sources of infection and routes of transmission. In addition, the total pig population in the study area was determined more accurately and the prevalence of cysticercosis investigated in pigs subjected to meat inspection at an approved abattoir. The questionnaires revealed a poor understanding of the disease, poor sanitation and hygiene, poor methods of pig husbandry and poor meat inspection and control in rural smallholder communities. There was no significant statistical difference in the proportion of households reporting evidence of epilepsy and owning pigs and those that did not. There is a strong evidence of a tendency towards an association between epilepsy, consumption habits and some identified epidemiological risk factors.

Antimicrobial drug resistance of Escherichia coli isolated from poultry abattoir workers at risk and broilers on antimicrobials.

Antimicrobial usage in food animals increases the prevalence of antimicrobial drug resistance among their enteric bacteria. It has been suggested that this resistance can in turn be transferred to people working with such animals, e.g., abattoir workers. Antimicrobial drug resistance was investigated for Escherichia coli from broilers raised on feed supplemented with antimicrobials, and the people who carry out evisceration, washing and packing of intestines in a high-throughput poultry abattoir in Gauteng, South Africa. Broiler carcasses were sampled from 6 farms, on each of which broilers are produced in a separate 'grow-out cycle'. Per farm, 100 caeca were randomly collected 5 minutes after slaughter and the contents of each were selectively cultured for E. coli. The minimum inhibitory concentration (MIC) of each isolate was determined for the following antimicrobials: doxycycline, trimethoprim, sulphamethoxazole, ampicillin, enrofloxacin, fosfomycin, ceftriaxone and nalidixic acid. The same was determined for the faeces of 29 abattoir workers and 28 persons used as controls. The majority of isolates from broilers were resistant, especially to antimicrobials that were used on the farms in the study. Overall median MICs and the number of resistant isolates from abattoir workers (packers plus eviscerators) tended to be higher than for the control group. However, no statistically significant differences were observed when the median MICs of antimicrobials used regularly in poultry and percentage resistance were compared, nor could an association between resistance among the enteric E. coli from packers and those from broilers be demonstrated.

A pilot study on post-evisceration contamination of broiler carcasses and ready-to-sell livers and intestines (mala) with Campylobacter jejuni and Campylobacter coli in a high-throughput South African poultry abattoir.

To assess post-evisceration contamination of broiler carcasses, 300 samples were randomly selected during routine slaughter in the winter of 2004. The samples originated from 50 chicken carcasses, taken directly after evisceration, as well as 25 samples from ready-to-sell packages of fresh intestines (mala) and livers. The samples were taken in batches over a period of 4 weeks to allow randomised sampling from different farms of origin. Conventional culture-based detection methods of Campylobacter spp. usually need 4-6 days to produce a result. The polymerase chain reaction (PCR) used for this study took less than 32 hours. The average contamination rates with Campylobacter in both the skin and liver samples were 24%, and 28% for intestines. Chicken and chicken products, especially livers and intestines, form an integral part of the traditional diet of many Black South Africans, as they are cheap and readily available in bulk and un-chilled for direct distribution, mainly through street vending and other informal retail outlets. This sudy showed that Campylobacter spp. are prevalent in poultry in South Africa. The handling of poultry meat and products contaminated with this organism in households and the potential for cross-contamination of other foods presents a high risk of infection to consumers in South Africa. The study also emphasised the need for further research in this field.

Microbiological quality of goat's milk obtained under different production systems.

In order to determine the safety of milk produced by smallholder dairy goat farms, a farm-based research study was conducted on commercial dairy goat farms to compare the microbiological quality of milk produced using 3 different types of dairy goat production systems (intensive, semi-intensive and extensive). A survey of dairy goat farms in and around Pretoria carried out by means of a questionnaire revealed that most of the smallholder dairy goat farms surveyed used an extensive type of production system. The method of milking varied with the type of production system, i.e. machine milking; bucket system machine milking and hand-milking, respectively. Udder half milk samples (n=270) were analysed, of which 31.1% were infected with bacteria. The lowest intra-mammary infection was found amongst goats in the herd under the extensive system (13.3%), compared with 43.3% and 36.7% infection rates under the intensive and semi-intensive production systems, respectively. Staphylococcus intermedius (coagulase positive), Staphylococcus epidermidis and Staphylococcus simulans (both coagulase negative), were the most common cause of intramammary infection with a prevalence of 85.7% of the infected udder halves. The remaining 14.3% of the infection was due to Staphylococcus aureus. Bacteriology of bulk milk samples on the other hand, showed that raw milk obtained by the bucket system milking machine had the lowest total bacterial count (16,450 colony forming units (CFU)/ml) compared to that by pipeline milking machine (36,300 CFU/ml) or hand-milking (48,000 CFU/ml). No significant relationship was found between the somatic cell counts (SCC) and presence of bacterial infection in goat milk In comparison with the herds under the other 2 production systems, it was shown that dairy goat farming under the extensive production system, where hand-milking was used, can be adequate for the production of safe raw goat milk.

Microbial quality of ostrich carcasses produced at an export-approved South African abattoir.

The aim of this study was to evaluate the microbial quality of ostrich carcasses produced in a South African export-approved ostrich abattoir. Ninety surface samples were collected from 30 ostrich carcasses at three processing points in the abattoir: after skinning, after evisceration, and after chilling. Samples were evaluated for aerobic plate counts, for levels of Pseudomonas spp., Enterobacteriaceae, and Staphylococcus aureus, and for the presence of Escherichia coli. Surface counts (means +/- standard deviations) at postskinning, postevisceration, and postchilling processing points were, respectively, 4.32 +/- 0.62, 4.21 +/- 0.63, and 4.57 +/- 0.48 log CFU/cm2 for total aerobes; 2.82 +/- 1.65, 2.86 +/- 1.53, and 3.75 +/- 0.94 log CFU/ cm2 for Pseudomonas spp.; 2.89 +/- 0.78, 2.90 +/- 0.53, and 2.38 +/- 0.67 log CFU/cm2 for S. aureus; and 2.55 +/- 1.53, 2.78 +/- 1.31, and 2.73 +/- 1.46 log CFU/cm2 for Enterobacteriaceae. Statistically significant differences were detected between the counts for the postskinning and postchilling processing points and between the counts for the postevisceration and postchilling processing points for total aerobes, Pseudomonas spp., and S. aureus. Of practical significance was the increase in Pseudomonas spp. counts on samples collected after chilling. Seventeen of 90 samples (18.8%) tested positive for E. coli. Counts for E. coli-positive samples ranged from 1.0 to 3.79 log CFU/cm2, with a mean count of 2.15 +/- 0.94 log CFU/cm2. The majority of the samples testing positive for E. coli were collected after evisceration.

The use of dried bakery products in a free-choice feeding method for small-scale broiler production.

Waste material from bakeries is an unconventional energy feed source which is available in sufficient quantities for use in small-scale broiler production in South Africa. Small-scale broiler producers do not have access to the computer programs required to balance home-mixed rations. This investigation confirms that the use of dried bakery products (DBP) in a 2-stage, free-choice method can be used to compensate for this lack. A total of 570 day-old male broiler chickens was assigned to 3 feeding treatments: the control group was fed a 2-stage feeding programme using standard commercial starter and grower rations. The 2nd group received a commercial starter ration up to Day 7 and was thereafter given a choice of a commercial starter ration with normal salt content (0.35%) and DBP. The 3rd group was fed a commercial starter ration up to Day 7, then offered a choice of commercial starter ration with a lower salt content (0.1%) and DBP. The low salt alternative was used to test whether the higher salt percentage in DBP influenced the choice of feed by the birds. It was found that the control group consumed significantly more feed (P < 0.05) and was significantly heavier (P < 0.05) than the experimental groups. However, there was no significant difference between the 2 experimental groups, which indicated that salt content did not play a role in the choice of ration. Feed consumption by both experimental groups was about one-third less than the control group, but the profit margin, as calculated using gross margin analysis, was approximately 15 % higher. It was therefore concluded that dried bakery products can be profitably incorporated as an energy feed source, using the free-choice feeding method, in small-scale broiler enterprises.

Public health risks associated with the utilisation of wildlife products in certain regions of Africa.

The authors describe the public health risks associated with wildlife products in certain regions of Africa. Most of the information presented is obtained from the Republic of South Africa, particularly the Kruger National Park. There are no statutory requirements in South Africa regarding the general inspection of game carcasses prior to sale: however, current regulatory inspection requirements are explained. Game farming systems in southern Africa are generally extensive systems with wild herbivores living in a near-natural 'free-ranging' state. Several pathological processes and disease entities have been confirmed in wildlife carcasses and these are listed with zoonotic implications.

Microbiological status of selected chicken carcases from a non-automated poultry processing plant.

The microbiological status of chicken carcases sampled at three different processing points in a South African Grade B poultry abattoir slaughtering ca. 750 birds per hour, was determined. Six skin samples and two meat samples were aseptically collected from different sites on each carcase. Total bacterial counts were performed at 25 degrees C, 37 degrees C and 43 degrees C and all colonies from plates showing between 30 and 300 cfu were characterised. Bacterial counts of the skin samples at 37 degrees C were consistently the highest, followed by those at 25 degrees C and then 43 degrees, but for the two meat samples the highest bacterial counts were found at 37 degrees C and the lowest at 25 degrees C. Neck skin counts were marginally higher than bacterial counts of the other skin samples. The Gram negative genera Escherichia and Acinetobacter were isolated most frequently at all three incubation temperatures and from all sampling sites, while the dominant Gram positive genera were Staphylococcus and Enterococcus. Escherichia isolates predominated on the skin sampling site cranio-dorsal to the pygostyle, whilst Staphylococcus isolates predominated on the skin sampling site caudal to the breastbone. Microbiological contamination is a major problem in the abattoir studied and further studies should therefore aim to determine points of maximum contamination in the processing line.

Arthritis in slaughter pigs.

Joints obtained from 192 pig carcases were examined by means of standard microbiological and macro- and histopathological procedures. Approximately 32% of the joints were considered normal; 35.5% showed lesions consistent with osteochondrosis and a non-specific synovitis was present in 24.4%. Only 6.1% of joints were arthritic and yielded either Staphylococcus aureus or Streptococcus spp. The remainder (2.3%) had periarticular lesions such as abscesses. The study emphasises that an accurate diagnosis and correct evaluation of pig carcases showing joint lesions, is absolutely essential if a high standard of meat inspection is to be obtained and unnecessary economic losses are to be avoided.

Haemophilus pleuropneumoniae in pigs: a review.

Haemophilus (Actinobacillus) pleuropneumoniae is a primary and specific pathogen of the respiratory tract and is an economically important pathogen of pigs. The disease is starting to cause peracute deaths in South Africa and the chronic form leads to deteriorating heard performance. This review highlights various aspects of the taxonomic, antigenic, and drug sensitivity characteristics of the bacterium and the epidemiology, clinical signs, pathology, serology and immunology, detection and diagnosis, differential diagnosis, prevention and control of the disease.