4.1. Factor Responsible for Bovine Liver Condemnations
Despite it small size, the highest relative losses (19.7%, 25.2%, and 17.7%) of liver from 2010 to 2012 was at the low throughput abattoir (X) contrary to the 11.3%, 10.8, and 7.6% and 13.5, 12.8%, and 7.7% losses recorded at the high throughput abattoirs (Y and Z) (Table 1
). The proximity of abattoir X to rural/smallholder farmers encourages patronage by them. Therefore, it was presumed that the high level of condemnation was a direct result of poor animal management. Farming in rural communities is characterized by low input and poor animal husbandry. Many farmers in these communities lack access to veterinary inputs necessary for the enhancement of livestock productivity [46
The leading cause of liver rejection at the abattoirs was fasciolosis, and a significant proportion of the liver was condemned either due to the presence of a cyst, Cysticercosis bovis
, or calcification (Table 1
and Table 2
). A number of factors could be responsible for the level of condemnation recorded in this study including, the presence of parasite (F. hepatica
, F. gigantica
, C. bovis
, and T. saginata
), changes in seasonal rainfall pattern, or animal ingesting metacercaria through ingestion of raw contaminated aquatic plants or drinking contaminated stagnant water or effluent from sewage treatment plant [47
]. The presence of various Fasciola
spp. in the EC Province has been previously reported, and the lack of adequate rainfall further encourages stagnant streams and rivers that harbour these parasites. The unsupervised irrigation fields often flooded with water promotes the proliferation of the infectious larval stages of the parasite. There are several studies [11
] that support the findings of this study, others [9
] reported a higher rate of condemnation due to fasciolosis.
The prevalence of cysticercosis reported in this study may be low, but the consequence of its zoonotic potential should not be ignored. The use of guard dogs for control and regulation of livestock movement in the rural communities may play a role in the observe prevalence. Dogs are the definitive host for Echinococcus granulosus
and can disseminate and contaminate the environment with the parasite, leading to disease transmission to ruminants and humans [15
]. Furthermore, the high rate of cysticercosis in developing countries is often associated with poor sanitary infrastructure, lack of public knowledge of the condition, and indiscriminate disposal of sewage [56
Fasciolosis and cysticercosis are important parasitic zoonosis of both veterinary and public health concerns. Even though humans are the accidental host, 2.4 million people in 61 countries are infected annually with Fasciola
spp., and about 180 million are at risk of infection. A significant percentage of human fasciolosis occur in Africa, while production losses due to the livestock industry are estimated over USD 2 billion [20
]. Furthermore, infection with Fasciola
is associated with decrease milk, meat, and wool yield, and with financial loss associated with the cost of veterinary medication [59
]. Severe damage to the bile duct and gall bladder of animals may lead death [60
Human cases of cysticercosis appear to be most prevalent in the Eastern Cape Province of South Africa, particularly in the poor rural areas of Ciskei and Transkei, where pigs are allowed to move freely and sanitation facilities are scarce or nonexistent. In West Africa, studies have shown epilepsy to be associated with neurocysticercosis in human and further suggest that it is prevalent in low or middle-income endemic countries in which approximately 30% of epilepsy may be attributable to neurocysticercosis [49
]. In animals, cysticercosis is associated with economic loss mainly due to condemnation, refrigeration, and downgrading of infected carcasses [63
]. The high rate of condemnation of the liver points to the failure of proper animal health management techniques at the farm level.
Liver abscessation, hepatitis, and fibrosis were responsible for a significant food waste during the RS and PMMI at the X, Y, and Z abattoirs for 2010, 2011, 2012, and 2013, respectively. An abscess is a localized collection of pus (dead neutrophils) separated from the surrounding tissue by a fibrous capsule formed following an infection. Grossly, it is an enlarged palpable lesion with fluctuating fluid. The most common pyogenic bacteria that causes abscesses in animals include Arcanobacterium
spp., and Fusobacterium
]. Both liver abscesses and fibrosis are common complications of migratory actions of parasite larvae, which elicit inflammatory responses, progressing to a fibrotic or granulomatous formation of tissues along the biliary tract. Ultimately, the tissue reaction pre-optimizes the conditions necessary for secondary bacteria to flourish [26
The common causes of hepatitis in animals include but are not limited to parasites such as Fasciola
spp., Dicrocoelium dendriticum
invasion and tunneling of the bile duct, and viruses and bacteria such as Hepatitis E virus, and Streptococcus
spp. (S. agalactiae/dysgalactiae/pyogenes/zooepidemicus
]. The rate of condemnation due to hepatitis reported in this study may be related to the animal origin, as cattle from Fasciola
infested areas are likely to increase the number of livers condemned for hepatitis. More so, animals from poorly resourced farmers lack adequate veterinary care and good husbandry [44
Several non-disease conditions such as melanosis, telangiectasis, and improper evisceration contributed considerably to liver rejection in this study. Although melanin is a natural pigment that occurs in the skin, hair nails and membranes, its abnormal accumulation in the liver causes dark pigmentation of the tissues leading to its condemnation. A report by Alton et al. [68
] concurs with the 2.6–4.9% condemnation rate of the liver due to pigmentation obtained in this study.
Telangiectasis is a visible dark purple, red sunken area of the liver that may be caused by focal necrotizing hepatitis, fibrosis, metabolic disturbance, and hepatic abscesses [69
]. In this study, the rejection of 3.1%, 2.4%, and 1.9% liver at abattoirs X, Y, and Z, respectively, due to telangiectasis was mainly because of the poor quality of its aesthetic value. Currently, abattoirs Y and Z export red meat to Europe, America, and Asia. There is a high demand for live animals as well as meat by consumers in these continents. For example, the value of red meat exports from South Africa has increased from R 791 million in 2013 to R 2.14 billion in 2016 [71
]. Such export market may be influenced by the quality of meat produced especially from diseases. Disease and pathologic conditions affecting the aesthetic of organs designated for the export market either directly or indirectly cause the rejection of such organs by the importer countries due to zoonoses threat and aesthetic reasons. Import restriction could adversely affect South Africa’s gross domestic product, the sustainable production of livestock, and farmers’ livelihoods.
Improper eviscerations led to a high number of liver wastage (4.8%, 12.4%, and 27.1%) during the PMMI (Table 2
). A study by Regassa et al. [13
] revealed similar finding to what was obtained in the present study. Evisceration problems are commonly associated with poor slaughter process [70
] and may lead to faecal contamination of organs with potentially infectious gut pathogens such as Salmonella
and Shiga toxin–producing Escherichia coli
]. In this study, evisceration problems were possibly due to untrained, inadequate and overburdened workers who usually rush to meet daily slaughter limits, hence the reduction in precision.
The EC Province is popular for livestock production, yet it is among the poorest in the country [34
]. Disease and non-disease factors described in this study impact negatively on food security, taking into account the high rate of fasciolosis and other conditions reported in this study, we assume that many preventable disease agents hamper livestock productivity. Disease, especially infectious disease, “is a main constraint of biologically efficient livestock production and both endemic and exotic disease results in mortality and morbidity and hence less food than should ideally be available in current farming systems” [19
]. The critical role of primary animal health in the production of healthy meat capable of supplying the protein needs of the populace and sustaining human health cannot be overstated. Food security programmes aimed at the sustainable production of sufficient amounts of affordable, high quality, safe food required to support the health and wellbeing of human populations is attainable if farms and production units adhere rigorously to strict and appropriate herd health plan.
4.2. Financial Loss Associated with Liver Condemnation
Food waste in the form of condemnation of the liver impacts negatively on food security, economy, export and domestic market. A total of R 343,330 (USD 45271.07) was lost due to the condemnation of liver in 2010, 2011, and 2012. Further loss calculated from the PMMI was R 59,227.2 (USD 5889.82). These findings are consistent with those of Tembo et al. [73
] in Dodoma, Tanzania, where USD 32,465.50 annual loss due to the condemnation of liver was reported. Furthermore, a high loss of USD 230,088 was reported by Yibar et al. [74
] in Bursa Province, Turkey. Apart from the monetary loss reported in this study, the amount of liver thrown away could substantially resolve hunger and food insecurity in an impoverished province such as the Eastern Cape where these condemnations are taking place. Beef liver has a protein content of 26%, and the average human protein requirement is 56 g per day [75
]. The condemned liver of only three months would be enough to feed 45 adults humans for a year. These condemnation rates may be grossly underestimated due to differences in the skills and experience of meat inspectors, the speed of the slaughtering activity, the meat inspection facilities, and sampling technique. Furthermore, considering the limitations of the traditional visual appraisal method of meat inspection, cysticerci could easily be missed as most cases of cysticercosis are light infections [12
Generally, some of the limitations encountered in this study included the use of only visual inspection for the detection of pathologic conditions; thus, only those liver with gross lesions were likely to be diagnosed. The abattoir records may also have been underestimated because of poor meat inspection and generally poor record keeping. Furthermore, the sampling technique used in abattoirs Y and Z may have excluded some animals with the pathologic liver. In spite of the limitations mentioned, the impact of this food waste on food security cannot be overemphasized. This study also shows the relevance of meat inspection and abattoir records in safeguarding public and animal health through preventive medicine and syndromic surveillance.