Inheritance patterns of the Polled and Scur genes in South African beef cattle breeds

The genetic mechanisms and inheritance patterns of the polled and scur phenotypes in local South African beef cattle breeds

Industry Sector: Cattle And Small Stock

Research Focus Area: Animal Health and Welfare

Research Institute: University of Pretoria

Year Of Completion: 2019

Researcher: E van Marle-Koster

The Research Team

TitleInitialsSurnameHighest QualificationResearch Institution
DrM.M.ScholtzPhDARC-AP
ProfEvan Marle-KosterPhDUP
MrsA. Theunissen MSc Vaalharts Research Station

Executive Summary

Introduction

It is standard practice to dehorn cattle at a young age by means of physical dehorning, but in most cases without the appropriate pain relief. The practice of dehorning has increasingly become a welfare concern and alternatives to dehorning are advocated worldwide. Breeding genetically polled cattle is a long-term, non-invasive and welfare friendly alternative to dehorning. Identification of genetically polled animals through a diagnostic test would therefore be advantageous, but a specific commercial diagnostic test for the polled phenotype is not currently available in South Africa.  The DNA tests that are available internationally are applicable to European Bos taurus breeds, which can give inconclusive results for indigenous South African and Sanga cattle breeds. Furthermore, the commercial diagnostic tests available for Taurine breeds can not identify carriers of either the scur gene or the African horn gene.

Over the past two decades commercial beef producers and feedlots in South Africa have indicated a preference for polled breeds, due to increased awareness of animal welfare and market preferences. In South Africa there are a number of polled breeds of European descent such as the Hereford, Angus, Charolais and Limousin, as well as a few local breeds, including the South African Bonsmara, Tuli and Drakensberger, that introgressed the polled gene. The Bonsmara breed requested research on the identification of homozygous polled bulls and the first research project in South Africa was performed at the Department of Animal and Wildlife Sciences, UP (Schmulian, 2006). This study was based on three Bonsmara families and the available microsatellite markers at that time were used. The study by Schmulian (2006) found linkage between the polled phenotype in the South African Bonsmara and alleles of nine microsatellite markers located on BTA1. Since the completion of this research project, the Bovine genome sequence has been completed in 2009 with high through-put molecular technology (Bovine HapMap Consortium, 2009), providing genomic information and high-density SNP chips.

The majority of previous research on the POLLED locus and polledness has been performed in European breeds, which does not provide a basis for identification of the causative mutation for polledness or scurs in indigenous South African cattle breeds. These breeds are genetically distinct from the European Bos taurus breeds (Makina et al., 2014) and besides the two main types of cattle, Bos taurus and Bos indicus, indigenous African cattle, such as the Sanga, are also found in South Africa.

Objective statement

This study focused on local South African beef cattle breeds to gain an understanding of the genetic basis and inheritance of the Polled and Scur genes by using pedigree data from phenotyped animals, as well as high density SNP data. The availability of DNA and high through-put molecular technology holds the potential to provide insight on the genetic mechanisms of polled and scurred animals with higher precision, compared to the microsatellite markers that were previously available.

Project Aims

  1. To evaluate whether the Celtic mutation on the POLL locus is the causative mutation for polledness in Bonsmara and Drakensberger
  2. To perform a genome wide association study of the Polled and Scur genes based on phenotypic data and genotypic data from the GGP Bovine 150K SNP bead chip
  3. To apply sequence data available from the Bovine Genomics Program to finemap the suspected regions for the Polled and Scur genes

Results

A total of 890 Bonsmara and 224 Drakensberger animals were screened for their status for the Celtic mutation at the POLLED locus using a PCR-based diagnostic test. It was possible to distinguish between heterozygous and homozygous polled individuals, but scurs could not be identified on a genotypic level based on the Celtic variant. The majority of animals screened, tested heterozygous polled, with homozygous polled animals occurring at a relatively low frequency. Based on the results of this Celtic screening, a total of 217 Bonsmaras (including homozygous polled, heterozygous clean polled and scurred animals) were genotyped using the GGP Bovine 150K SNP bead chip. Additional genotypes from the Bovine Genomics Program (BGP) were also included in this study.

Haplotype analysis of the POLLED locus revealed a reduced genetic diversity around the Celtic allele, with only two haploblocks (1.0-2.2 Mb) observed in the homozygous polled animals investigated. One of these haploblocks of six SNPs encompassed the Celtic mutation and presented only three distinct alleles with major differences in terms of frequencies. This result suggests that the Celtic allele was introgressed in the Bonsmara breed from a very limited number of founders. A low haplotype diversity combined with an intense selection on the polled phenotype in the Bonsmara breed can result in the selection of deleterious alleles linked with the Celtic mutation through a hitchhiking mechanism. Therefore, it is of primary importance to maintain some genetic variability around the Celtic allele.

Preliminary results of the GWAS study, based on 150k SNP chip data, indicated significant association for the scurs phenotype with three SNPs on BTA5, which contradicts previous findings that mapped the SCURS locus to BTA19. For the POLLED locus, preliminary results show significant association between the polled phenotype and BTA1, as expected. Of interest is another significant association with the polled phenotype that were observed on BTA28, which was not reported in previous studies. The significant SNPs that were identified in the GWAS analysis of the POLLED and SCURS loci will be annotated to identify candidate genes and to investigate the potential significant physiological pathways of these SNPs.

Conclusion

The POLLED Celtic variant was validated as the causative mutation of polledness in three South African beef cattle breeds and can be used as an efficient diagnostic test for polledness. This study also highlighted the current difficulties and limitations of accurate phenotypic recording of the horn status. It also confirmed that scurs cannot be identified on a genotypic level with the Celtic screening. Preliminary results of genotypic SNP data indicated significant association for the scurs phenotype on BTA5 in the Bonsmara, but these results need to be further investigated.

The following scientific output were achieved for the project:

Grobler, R., Visser, C. & van Marle-Köster, E., 2017. Accelerating selection for polledness in the South African Bonsmara using DNA technology. 50th South African Society for Animal Science (SASAS) Congress, Port Elizabeth, 18 – 21 September 2017.

Grobler, R., van-Marle-Köster, E., Visser, C.& Capitan, A., 2018. Haplotype variation at the POLLED locus in the South African Bonsmara cattle breed. World Congress on Genetics Applied to Livestock Production (WCGALP) 11-16 February, Auckland.

Grobler, R., Visser, C., Capitan, A. & van Marle-Köster, E., 2018. Validation of the POLLED Celtic variant in South African Bonsmara and Drakensberger beef cattle breeds. Livestock Science. 217, 136-139.

Popular Article

Introduction

Identifikasie van poena status in die Bonsmara met behulp van DNA tegnologie

Rulien Grobler (PhD Kandidaat)

Departement Vee- en Wildkunde, Universiteit van Pretoria

Inleiding

Die voordele van poenskop beeste vir die kommersiële vleisbeesindustrie is alombekend en wêreldwyd word die druk vir meer menslike praktyke in terme van dierebehandeling hoër, as gevolg van die impak op dierewelsyn. Alhoewel die opsie daar is om kalwers te onthoring, dui navorsing aan dat dit n pynvolle prosedure is, ten spyte van die tegniek of voorsorgmaatreëls wat gebruik word. Behalwe dat die onthoring van kalwers nie welsynsvriendelik is nie, is dit ook tydrowend en arbeidsintensief,en veroorsaak dit ook stres wat die groei van die kalf negatief kan affekteer. Hierdie faktore het dan ook ‘n verdere ekonomiese implikasie vir die boer. Dit is ook n opsie om poenskop beeste te selekteer gebaseer op fenotipiese rekords, maar hierdie proses is egter tydrowend en oneffektief, en veroorsaak stadige genetiese vordering. Deur gebruik te maak van DNA tegnologie om poenskop diere te identifiseer, kan seleksie vinniger en meer effektief plaasvind en genetiese vordering sal ook vinniger toeneem. Verder is dit ook ‘n welsynsvriendelike alternief, so wel as n langtermyn oplossing vir die onthoring van kalwers.

Poenskop oorerwing

Die Poena geen is outosomaal dominant en indien teenwoordig, sal die uitdrukking van die horing fenotipe onderduk word. Daar is twee allele teenwoordig by die Poena geen, P en p, en diere wat die dominante P alleel dra is fenotipies poenskop. Homosigotiese poenskop diere dra twee dominante P allele (PP), terwyl heterosigotiese poenskop (Pp) diere een dominante P alleel dra en een horing alleel. Dus, diere wat twee p allele dra het dan die horing fenotipe (pp). As gevolg van dominansie, kan daar nie onderskei word tussen die homosigoot en heterosigoot poena fenotipe nie. Dus is dit nodig vir n genetiese toets om draers van die poena en horing allele te identifiseer.

Afhangende van die poena status van die moer en vaar, word die poena allele in verskillende proporsies oorgedra na die nageslag (Figuur 1). Bv. Wanneer n homosigotiese poena (PP) bul, wat dan twee dominante poena allele dra, geteel word met n horing koei (pp), is daar ‘n 100% kans dat die nageslag fenotipies poenskop sal wees, omdat die nageslag een dominante P alleel kry van die vaar en een horing alleel van die moer. Maar wanneer n heterosigotiese poena (Pp) bul gebruik word, verminder die kans vir poenskop nageslag met 50% (Figuur 1).

Figuur 1 Die moontlike genotipiese proporsies vir verskillende paringsituasies van horing, hetero- en homosigotiese poenskop individue

Die oorerwing van die poena geen word verder gekompliseer deur die scurs fenotipe, as gevolg van epistatiese interaksie tussen die Poena en Scurs gene. Scurs is klein horingagtige vergroeisels wat op dieselfde plek as horings op die kop voorkom, maar hierdie abnormale vergroeisels is losweg aan die skedel geheg en is beweeglik (Figuur 2). Scurs is geslagsbeïnvloed en word gevolglik verskillend oorgeërf in manlike en vroulike diere. Dit is waargeneem dat scurs kan voorkom in diere wat heterosigoties poenskop is, en dat scurs meer in manlike diere as in vroulike diere voorkom.

Figuur 2 Die poenskop (A en B) en variasie van die scurs (C – F) fenotipes soos waargeneem in die Bonsmara

Die Poena Projek by UP

Die Poena geen is geleë op chromosoom 1 (BTA1) en minstens twee verskillende variante is verantwoordelik vir die poenskop fenotipe in beeste, naamlik die Celtic (PC) en Friesian (PF) variante (Allais-Bonnet et al., 2013).  Die Celtic (PC) variant is verantwoordelik vir die poenskop fenotipe in die meeste Bos taurus rasse van Europese herkoms, terwyl die Friesian (PF) variant hoofsaaklik voorkom in die Holstein Friesian ras.

In samewerking met ‘n navorser van Frankryk (INRA), is Bonsmara diere getoets vir beide die Celtic (PC) en Friesian variante (PF). Dit is vasgestel dat al die Bonsmara diere met n poenskop fenotipe, dra ten minste een alleel van die Celtic variant en geen diere is positief getoets vir die Friesian variant nie. Hierdie bevinding is in lyn met die geskiedenis en ontwikkeling van die Bonsmara vanuit n Europese Bos taurus ras. ‘n Groter groep Bonsmaras is getoets vir die Celtic variant (PC) en dit is bevestig dat die Celtic variant (PC) van die Poena geen verantwoordelik is vir die poenskop fenotipe in die Suid-Afrikaanse Bonsmara (Grobler et al., 2018).

Deur gebruik te maak van ‘n haarmonster, word DNA geëkstraeer uit die haarwortels. Die DNA word dan gebruik om die dier te toets vir die Celtic variant (PC) deur gebruik te maak van ‘n PCR-gebaseerde diagnostiese toets. Gevolglik kan draers van die PC variant geïdentifiseer word en sodoende kan diere ook as homo- of heterosigoties poena geïdentifiseer word op ‘n genotipiese vlak.

Bonsmara bulle en koeie, asook sekere kalwers, is uit spesifieke kuddes geselekteer om poenskop diere te identifiseer en tot dusver is n totaal van 890 Bonsmaras getoets vir die Celtic variant (PC) met die bogenoemde diagnostiese toets. ‘n Hoë frekwensie poenskop diere is waargeneem, waarvan die meerderheid diere heterosigoties poena getoets het (Figuur 3). Dit beteken dat hierdie diere slegs een PC alleel dra, asook een horing alleel, wat dan moontlik oorgedra kan word aan die dier se nageslag. Alhoewel homosigotiese poena diere wel waargeneem is, is dit waargeneem in slegs 12% van die diere wat tot dusver getoets is (Figuur 3). Die Bonsmara diere wat horing getoets het, is by n relatiewe hoë frekwensie van 42% waargeneem (Figuur 3). Dit is tog nodig om te noem dat die meerderheid van die homosigotiese poenas in een kudde waargeneem is wat vir meer as twee dekades al spesifiek selekteer vir die poenskop fenotipe. Alhoewel hierdie toets kan onderskei tussen homo- en heterosigote poenskop diere, kan die toets nie scurs op ‘n genotipiese vlak identifiseer nie en verdere navorsing is nodig vir scurs.

Figuur 3 Die genotipe frekwensie van die Celtic variant (PC) soos getoets in 890 Bonsmaras

Implikasies vir SA Bonsmara

Die diagnostiese DNA toets kan effektief gebruik word om heterosigotiese en homosigotiese poena diere te identifiseer op n genotipiese vlak. Hierdie toets kan egter nie gebruik word om scurs op n genotipe vlak te identifiseer nie, omdat beide poenskop en scurs diere genotipies heterosigoties poenskop toets (Pp). Dit is dan juis waarom dit belangrik is om die horingstatus van diere vroegtydig en akkuraat aan te teken. Die poenskop fenotipe is maklik om te observeer en verander nie tydens die dier se leeftyd nie. Die scurs fenotipe is egter moeiliker om aan te teken, omdat dit dikwels verwar word met horings of eers later uitgedruk word. Daarom word dit aanbeveel dat beeste ondersoek word by n jong ouderdom (gewoonlik tydens speen), asook tussen 18 en 24 maande.

Met behulp van hierdie DNA tegnologie kan die poena status van diere vroegtydig geïdentifiseer word, wat sodoende die genetiese seleksie van poena diere sal vergemaklik, asook versnel. Verder hou dit ‘n ekonomiese voordeel vir telers in wanneer gesertifiseerde poenskop bulle bemark kan word. Meer poenskop diere in die mark sal ook ‘n voordeel inhou deur arbeidskostes te verlaag en diere welsyn te bevorder omdat die onthoring van diere dan metteryd nie meer nodig sal wees nie. Die relatiewe hoë frekwensie van horing diere wat waargeneem is bevestig juis die belangrikheid van ‘n DNA toets, deurdat telers eers die poena status van diere op ‘n genotipiese vlak moet bevestig voordat vermeende poena diere ingesluit word in ‘n paringsprogram. Dit is veral belangrik vir bulle wat vir teeldoeleindes en veilings gebruik gaan word.

Erkennings

Dankie aan elke boer wat haarmonsters en inligting bygedrae het vir die Poena projek, en ook spesifiek vir Charl Uys vir sy hulp. Dankie aan Prof E. van Marle-Köster en Dr C. Visser; die studiepromotors op die PhD projek. Dank aan RMRD SA en die NRF vir befondsing.

Verwysings

Allais-Bonnet et al., 2013. PloS ONE. 8, 1-14.

Grobler et al., 2018. Livestock Science. 217, 136-139.

Footer and Tags and Categorisation

Please contact the Primary Researcher if you need a copy of the comprehensive report of this project on :LindeD@arc.agric.za

Supplementation of ruminants on winter pastures

Supplementation of ruminants on winter pastures

Industry Sector: Cattle and Small Stock

Research focus area: Livestock production with global competitiveness

Research Institute: University of Pretoria

Researcher: Prof Willem.A. van Niekerk PhD (Agric) Animal Science

Research Team:

TitleInitialsSurnameHighest Qualification
ProfLourens. J.ErasmusPhD (Agric) Animal Science
DrA.Hassan
PhD (Agric) Animal Science
MrR.J.Coetzer
MSc (Agric) Animal Science
MrHMynhardtMSc (Agric) Animal Science

Final report approved: 2016

Aims of the project

  • To develop a cost-effective supplementation strategy for ruminants under low quality winter forage conditions
  • To maintain body weight during the wineter season by assessing different sources and levels of nutrients that enhances poor quality roughage utilisation
  • To investigate intake, fiber degradation and microbial protein production when various types and levels of nutrients are supplemented to ruminants kept at maintenance under extensive conditions

Executive Summary

A series of studies was conducted to evaluate differential energy and nitrogen (N) sources as supplemental feed to sheep grazing low quality winter grazing in the High veldt. Knowledge on supplementation under local conditions are limiting as the majority of supplementation studies are funded and performed in the more temperate areas. Results indicated that higher N and energy inclusion levels are necessary to optimize ruminant production under local conditions compared to temperate areas. In addition, the ratio of fermentable energy to available protein is an important parameter in optimizing supplementation programs. It is concluded that the supplementary recommendations from the current feeding tables does not describe the requirements and nutrient quality of the tropical grasses satisfactorily and as such, cannot be used to predict supplementation responses by the tropical forage fed ruminant.  del can be used for further sensitivity analyses and “what if” scenarios as well as a database to answer specific questions.

Popular

SUPPLEMENTATION OF SHEEP GRAZING LOW QUALITY GRASSES WITH UREA AND STARCH

BY:  *H. MYNHARDT, W. A. VAN NIEKERK AND L. J. ERASMUS, UNIVERSITY OF PRETORIA

Every year sheep might lose up to 30% of their summer body weight gain during the dry winter periods in the high veldt.  While these weight losses have an economic impact on its own, it also is associated with an increased susceptibility for diseases and parasitic infestations and decreased reproductive performances. It generally is considered that protein or non-protein nitrogen (NPN) supplementation is necessary to limit these weight losses during these periods. However, due to the type of grass found in the High veldt area of Southern Africa, data is limiting on the effects of supplementation of ruminants grazing these types of grasses (See box: Differences between C4 and C3 grasses). As such, supplementations recommendations derived from current feeding tables seldom satisfy the needs of the grazing ruminant in Southern Africa. Therefore, a series of studies was conducted at the University of Pretoria to determine and quantify the requirements of the ruminant grazing low quality Eragrostis curvula hay commonly found in the Southern Africa High veldt.

* References and correspondence can be obtained from the author: hermanmynhardt@yahoo.com


Box 1: Differences between C4 and C3 Grasses

The acronyms C3 and C4 refer to the first product of the photosynthetic processes in the respective grasses with the first product of photosynthesis in the C3 grass being phosphoglycerate (a 3 carbon structure) while for the C4 plant, the corresponding molecule is a 4 carbon molecule (oxaloacetate). C3 grasses are temperate grasses and are adapted to the temperate regions of the world where rainfall is more constant with maximum temperatures seldom topping 22 OC. In contrast, C4 grasses are more adapted to the subtropical and tropical climates with temperatures frequently topping 25oC during the growth period. These areas also are associated with seasonal droughts and the occasional frost. Due to these extremes in temperatures and seasonal droughts, C4 grasses contain more bundle sheath cells and less available nutrients compared to C3 grasses during all maturity stages. Ruminant production therefore in general is significantly lower in ruminants grazing C4 grasses compared to temperate C3 grasses, especially during the dormant stage of the grass where lignification of the C4 grasses reduces the availability of the nutrients even further. As such, supplementation requirements and responses differ between ruminants grazing these grasses. However, the majority of supplementation studies in the past have been conducted on C3 grasses as it is found more in the European countries where research funding is more available. As such, as more studies conducted on low quality C3 grasses are incorporated in the current feeding tables, supplementation requirements derived from these tables to the low quality tropical forage fed ruminant are not always accurate. As such, the need was established to conduct research through the financial support of the **RMRD-SA on the nutritional requirements of the low quality tropical forage fed ruminant in order to improve ruminant production in Southern Africa.


*RMRD -SA – Red Meat and Research Development, South Africa



Results and Discussion

Forage intake and digestibility was not influenced by either the level of urea or starch supplementation to the wethers. However, CP-balance, measured as CP intake – CP excretion in the faeces and urine, increased from 12.5 g CP/day in the LU wethers up to 70 g CP/day in the EHU wethers. Based on these observations, only the EHU treatment supplied sufficient protein to potentially satisfy the needs of the 50 kg wethers as they require 65 – 70 g CP for maintenance. These recommendations are significantly higher than the recommendations set in the current feeding standards, however, it is in alignment with the observations and recommendations set out by **Leng (1995) studying ruminants grazing tropical grasses in Australia.

Forage intake and digestibility was not influenced by either the level of urea or starch supplementation to the wethers. However, CP-balance, measured as CP intake – CP excretion in the faeces and urine, increased from 12.5 g CP/day in the LU wethers up to 70 g CP/day in the EHU wethers. Based on these observations, only the EHU treatment supplied sufficient protein to potentially satisfy the needs of the 50 kg wethers as they require 65 – 70 g CP for maintenance. These recommendations are significantly higher than the recommendations set in the current feeding standards, however, it is in alignment with the observations and recommendations set out by **Leng (1995) studying ruminants grazing tropical grasses in Australia.

HIGHER LEVELS OF PROTEIN AND ENERGY SUPPLEMENTATION IS NECCESARY TO OPTIMISE THE GRAZING RUMINANT IN THE S.A. HIGH VELDT DURING THE DRY WINTER MONTHS

An important parameter in ruminant nutrition is microbial protein synthesis (MPS) as it gives an indication of the efficiency of the rumen microbes. During the dry winter months, MPS generally decreases due to the lack of available nutrients in the roughages (Leng, 1990, 1995) which decreases the productivity of the animal which is experienced as weight loss by the farmer.  In this study, MPS increased almost 50% from 78 g MPS to 106 g MPS as the level of starch supplemented was increased from 200 (LS) to 280 (HS) g starch/day. This observation is in agreement with suggestions made by Leng, (1990; 1995) that energy is an important nutrient driving MPS in the tropical forage fed ruminant, provided that the protein requirements of the ruminant have been met. Interestingly, energy supplementation for the temperate forage fed ruminant is not always advocated as these grasses contain higher concentrations of water soluble carbohydrates compared to the tropical grass.

Based on the above results, higher levels of both protein and energy supplementation is necessary to optimise ruminant production during the dry winter months in the High Veldt. The question now was asked whether there was an “ideal” quantity of protein and energy to be supplemented to ruminants grazing low quality “tropical” forages.

Graph 1 is a schematic representation of MPS per unit CP intake (MNS: N intake) while Graph 2 represents the mean rumen ammonia nitrogen (RAN) concentration as influenced by the ratio of starch supplemented to available protein intake.

Graph 1

Urea supplementation across all three starch treatments affected the MPS: CP ratio similarly with the ratio decreasing from almost 3 to below 1 where the wethers were supplemented with the higher urea treatments (HU and EHU). It is important to note that alleviated MPS: CP levels (above 1) could be indicative of CP deficiency as more microbial protein was synthesized in the rumen compared to dietary CP intake. The additional CP required to produce the microbial protein under these circumstances is derived from body protein catabolism which in itself, is an inefficient process, resulting in an excessive body weight loss. As such, in this trial, it is suggested that the protein intake of the wethers supplemented with at least 26.4 g urea/day (HU) was sufficient to meet the requirements of the wethers.

Graph 2

An inverse relationship was observed between RAN and the ratio of starch: digestible protein intake (Graph 2) with RAN decreasing and plateau between 5 and 10 mg RAN/ dL rumen fluid as the ratio increased. An inflexion point was observed where RAN increased exponentially to levels as high as 25 and even 30 mg RAN/dL rumen fluid as the ratio decreased below 2: 1. This graph highlights the importance of supplementation of both rumen available energy sources (starch in this instance) as the supplementation of only RDP sources to the ruminant could lead to an increased risk of ammonia toxicity under these circumstances.

Conclusion

The results from this study suggest that the supplementation requirements of 50 kg wethers grazing low quality tropical forages (2.7% CP) differs to the current feeding standards as:

  • Higher levels of protein (urea supplementation up to 26.4 g urea per day per wether or 3% urea of the total DM intake) is necessary to optimise CP balance in the tropical forage ruminant.
  • Starch supplementation (up to 280 g/wether/day or almost 20% of the total DM intake) in addition to urea supplementation is necessary as tropical grasses not only are deficient in protein, but also in easy available energy.
  • For wethers grazing low quality tropical grasses, the ideal ratio of starch supplemented to digestible protein intake lies between 2 and 3: 1.
  • Additional research is necessary to study the effects of other energy sources and protein sources on rumen environment and the production parameters of the tropical forage fed ruminant as these sources might have different availabilities compared to urea and pure starch within the rumen.

The authors wish to thank the Red Meat Industry and Research Development (RMRD) for their financial support of this study.

Please contact the Primary Researcher if you need a copy of the comprehensive report of this project –
Willem van Niekerk on willem.vanniekerk@up.ac.za

Formal and Informal Red Meat Industry in the Western Cape

Hidden in Plain Sight: A Regional Inquiry into the Size, Scope and Socioeconomic Effects of the Western Cape’s Formal and Informal Red Meat Industries

Industry Sector: Cattle and Small Stock

Research Focus Areas: Animal Health and Welfare; Animal Products, quality and safety, nutritional value and preference; The economics of red meat consumption and production in South Africa

Research Institute: Agriculture Research Institute – Animal Production Institute

Researcher: Dr Nick Vink PhD (Agric)

Title Initials Surname Highest Qualification
Mr. Michael McCullough M

Completion Date : 2018

Aims Of The Project

  • 3.1 To determine and report the size and scope of the informal red meat I industry as well as the informal industry’s effects on food safety, animal health and l welfare and food security with an initial focus on the Western Cape.
  • 3.2 To determine and report the size and scope of the formal red meat industry as well as the formal industry’s effects on food safety, animal welfare and food security with a primary focus on the Western Cape.
  • 3.3 To create and test a combined quantitative and qualitative methodology for determining the size and scope of the red meat industry in South Africa with a primary emphasis on the informal sector, a secondary emphasis on the formal sector as well as recommendations for improving current levels of food safety, animal welfare and food security.

Executive Summary

Hidden in Plain Sight

The genesis of Hidden in Plain Sight was two previous studies of red meat marketing systems: one in a rural Municipality in the Western Cape that discovered an informal shadow industry operating alongside a formal system of abattoirs, supermarkets and independent butcheries; the other in the townships and informal settlements of Cape Town that described an informal marketing system filling a vacuum created by the abdication of the formal system of supermarkets and butcheries. Beyond the scope of both studies was an appreciation of the size and scope of the Province’s informal systems of red meat production, processing and distribution. Hidden in Plain Sight attempts to determine size and scope of the Province’s informal red meat industry, its effects on food security, food safety and animal health and welfare.

Informal livestock farmers pasturing cattle and sheep primarily on Municipal land as well as raising pigs in improvised piggeries furnish livestock for informal processing; i.e. outdoor slaughter and indoor butchery in unlicensed facilities such as home kitchens and food stands. One and two kilo ‘value packs’ are then sold from kitchen butcheries in rural communities. Braai stands located near taxi ranks, train stations and major intersection in the former townships of Khayelitsha, Gugulethu and Nyanga in the Cape Town Metropole receive live animals directly from informal producers located on City land surrounding these communities. The animals are slaughtered on the sidewalk in front the stands or in any other adjacent open space. The muscle meat is sliced into strips and braaied, the heads are skinned, split and charred and the offal is piled on the counter for sale to hawkers or take-home consumers.

The informal system exists in both urban and rural areas to serve the 2.6 million low to very low income households in the Western Cape. In addition to low incomes many urban and rural households live in virtual ‘food deserts’ where, in the absence of transportation either public or private access to food sellers is at best difficult.  Low to very low incomes and lack of access expose over half of the Province’s households to food insecurity and place 29 percent at risk of hunger.

An expectation at the inception of this study was that size and scope of the informal system although unknown would rival the formal red meat system and would be sufficient to serve a significant percentage of the Province’s food insecure households. Such was not the case. Survey data based on inspections of informal production sites throughout the Province, census  and interview data from the Veterinary Service and the Farmer Support and Development programmes of the Western Cape Department of Agriculture and interviews with Municipal Social Development officials yield numbers of informal produced livestock clearly insufficient to serve a fraction of households at risk for hunger. Three recommendations are offered to increase the capacity of the informal industry to serve food insecure households: conduct a comprehensive inventory of public land suitable for informal production; establish an informal production, processing and distribution pilot project in each District Municipality; investigate existing parallel formal – informal marketing systems in Latin America; develop a prototype two tiered regulatory frame work to facilitate food security whilst ensuring food safety.

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Magazine Article

Michael McCullough

When South African consumers walk into their local supermarket to shop for beef, lamb or pork they expect a fresh, high quality, attractively packaged, nutritious product and they get it. No need to worry about the safety of the product. South African cattle, sheep and pigs are given a through once over before they set foot in an abattoir. Any animal injured, unfit or suspected of disease is promptly rejected, condemned and disposed of. It’s not a business decision, it’s the law.

What supermarket shoppers are beginning to worry about is the possibility the meat they serve their family and friends could come from terrified, abused or injured animals. They want to know that the slaughter process is humane and animal suffering is minimised. That may sound like a contradiction in terms but it’s not. Here’s why:

  • After arrival at the abattoir animals must be rested for at least an hour. The animals must calm and ready for inspection just before they are taken into the abattoir.
  • After passing single file through a narrow corridor each animal is taken individually into a slaughter room and placed in a narrow box or a harness. This happens out of sight of the other animals to reduce stress on those queued up behind.
  • The actual killing must be painless. Animals are stunned with a strong but not fatal electric shock or with a captive bolt pistol that delivers a sharp blow to the animal’s forehead.
  • While the animal is unconscious both the arteries and veins in the neck must be severed quickly and accurately. Contrary to the movies where the victim drops dead just after his throat is cut; if one or more veins or arteries are missed the animal may take from a minute to five minutes to die. If the stun wears off before enough blood is lost to shut down the brain the animal can experience pain.
  • Stunning and wielding the knife is hard, skilled and dangerous work. Humane slaughter depends on workers who are alert and careful. Tired operators may become careless or insensitive to animals’ welfare therefore abattoirs insure their operators take regular rest periods to maintain their skills.

The animal’s carcase is then moved to a high ceilinged room and hoisted head down to finish the bleeding process. The carcase is now ready for butchery. For consumers preferring kosher or halal meat the procedure is slightly different. For kosher slaughter no stunning is allowed but to minimise suffering the arteries, veins, vagus nerve, trachea and oesophagus are severed in a single quick sweep of a very sharp knife. Halal abattoirs may elect to stun the animal. Properly done the animal is unconscious in three seconds because severing the vagus nerve is like shutting down the body’s neurological switchboard.  Flip the switch and the lights go out.

One thing consumers shopping at their neighbourhood supermarket or butchery don’t want to worry about is whether the chops and steaks they’re buying are safe to eat. Should they? After all nobody wants to have friends and family or even worse, their boss over for a braai and find out later that everyone wound up at the clinic with gastric ‘distress’ or worse. This threat is all but completely short-circuited by post slaughter meat inspections, cold chain management and strict hygiene practices from the abattoir to the wholesaler to your butcher to your shopping cart.  Here’s how it works:

  • After the carcase has bled out, the head and hide are removed taking care to make sure the hair side of the hide doesn’t touch the meat. After all the animal has never seen a shower stall so the hide is pretty grimy. For this reason anything that touches the hide shouldn’t touch the meat such as dirty hands, in in the low income housing areas next to most country towns and in densely populated urban communities like Khayelitsha in Cape Town implements, dirty hands or soiled protective clothing.
  • Organs like the gut and the gall bladder contain seriously infectious bacteria like salmonella so the viscera must come out intact (the viscera is the sack that contains digestive tract). If it splits like a cheap trash bag on the way out everything you don’t want to touch the meat goes everywhere including all over the carcase. Assuming everything comes out as planned it’s time for final butchering and trimming.
  • The carcases are halved, the spines removed, all the other inedible bits and pieces as well as any contaminated meat is cut out and discarded. The carcase is washed and chilled. The slaughter and butchering processes are done.

From here to your grill is just a matter of maintaining the cold chain – keeping the carcase clean and chilled — until it passes through the wholesaler’s cold storage on its way to your neighbourhood supermarket or butchery. The carcase is then cut into meal sized portions, wrapped, marked, priced and put in the display case. Done and dusted.

Just as every coin has two sides so does every industry. The meat industry is no exception. The formal, visible side of the industry serves the middle and upper classes and the informal, mostly invisible side serves everyone else.

When low to very low income consumers shop for beef, lamb or pork do they expect high quality and fancy packaging?  Do their questions about nutrition go much further than Will it satisfy my family’s hunger or not?  Does price matter more to this consumer than where the animal came from, what condition it was in and how did it die? It’s safe to say that putting enough affordable on the table comes first; nothing else really counts.

For these reasons a growing number of South Africans are turning away from supermarkets and butcheries to buy meat produced and processed in their own communities. Why are a growing number of consumers in low income urban communities bypassing abattoirs, supermarkets and butcheries?

Until recently not much was known about the informal red meat industry in the rural Western Cape. It was not completely invisible but rather operated in the shadows just out of sight of most supermarket and butchery shoppers.  Informal stock producers who supply this industry aren’t usually landowners and depend heavily on leased Municipal property adjacent to low income housing areas and shanty towns. Cattle and sheep producers graze their animals where they can find grass and water. However pig producers must confine their animals to keep them from roaming. They build pens from scraps of lumber, sheet metal or other discarded building materials. Pig can’t be kept just anywhere; they need a source of water for mud to wallow in during the warm months (they don’t sweat enough to keep cool). The smell of an informal pig kraal is unforgettable so most are located away from housing. Although neighbours don’t seem to mind cows or sheep wandering through the community they usually draw the line at somebody else’s pig rooting in their garden.

When an informal producer is ready kill a pig, for example he or she spreads the word and takes orders. When it comes time to slaughter the producer recruits several volunteers; puts a barrel or large pot of water to boil on a wood fire and brings the pig forth. The pig is stunned by one or more blows between the eyes with a heavy hammer. A long sharp knife is inserted to the hilt just above the breastbone, twisted vigorously and pulled out. If all goes well (and it sometimes doesn’t) the pig will bleed out rapidly. Unfortunately most informal sites don’t have a convenient tree to hoist the pig so that it bleeds out completely. It’s often left on the ground to ooze blood until the time seems right to dip the carcase into the hot water to loosen the hair and underlying membrane. After the hair is scraped off down to the white skin it’s time to remove the head, the viscera and the rest of the internal organs. The pig should be hung for a day and allowed to cool. In practice this seldom happens. A carcase hanging from a tree overnight is likely to attract unwanted attention from the authorities. So the carcase is immediately butchered into saleable portions, refrigerated or frozen if possible and sold to local consumers. The helpers are usually rewarded with a share of the meat, the head and the offal.

The routine for cattle and sheep is similar except for the extra volunteers needed to handle a 150 kg cow carcase. Cow hides are removed with a knife and sheep skins are pulled off by hand. Unlike a pig no boiling and scraping is necessary.  Contamination from faeces and urine is hard to avoid and accidents often occur when the processing crew is tugging the heavy, slippery viscera out of the gut cavity not to mention the near certainty of hair and dirt on the meat. The carcase is usually rinsed with water carried to the slaughter site in buckets.  Given the rough ad tumble nature of informal slaughter it’s surprising that reported cases of food poisoning from informally sourced red meat are so rare as to be non-existent.

In Khayelitsha, a large densely populated suburb of Cape Town the informal system is not only out of the shadows it’s out loud and proud. Next to every train station, taxi rank and surrounding every major street intersection sidewalk braai stands do a thriving business in grilled beef, pork and mutton. Tens of thousands of commuters stop by these stands every day to pick up a takeaway meal on the way to and from work. Think off these stands as fast food outlets for the black urban working class. Just like the ‘McWhatevers’ in other neighbourhoods      braai stands offer accessible and  affordable (but not necessarily inexpensive) meat to consumers without the means or time to buy meat fresh, take it home, refrigerate it and cook it later. The big difference between fast food outlets in neighbourhoods like Khayelitsha and outlets other less crowded and more affluent neighbourhoods is how the meat gets there and what happens when it arrives.

Live animals are brought in from surrounding communities and slaughtered on sidewalks in front of the stands, alleys behind the stands or any unoccupied space. A source of water to rinse the carcases is strictly optional. The muscle meat is sliced into strips and immediately grilled. The heads are skinned or scraped, split and charred for serving. The offal is piled on tables and sold to customers for home consumption.

To outsiders the scene is a bloody, chaotic and cruel public health disaster. Are there issues with quality? Yes. Nutrition? Absolutely. Packaging? Of course. Safety? Afraid so. Access? No. Affordability? No. To Khayelitsha residents braai stands are a local informal industry that meets their community’s needs because the formal industry is either unwilling or unable to do so.

So which consumer model makes will prevail? The supermarket model that creates expectations of quality, safety and nutrition wrapped up in attractive packaging but comes at a high price? Or the braai stand/informal butchery next door that makes up for little or no packaging, no guarantees of quality, safety or nutrition but delivers affordable prices and accessibility?

For the foreseeable future the answer is both. Consumers who are willing and able to pay a price premium for the value added by abattoirs, wholesalers and supermarkets in exchange for guarantees of quality, safety and nutrition will continue to do so because they can. Consumers who lack the means to pay for those kinds of guarantees and who must take their chances in return for accessible and affordable meat will continue to do so because they must.

Please contact the Primary Researcher if you need a copy of the comprehensive report of this project – Dr Nick Vink  on nv@sun.ac.za

Heartwater survey on changes and causes

A Survey of veterinary and farmer experiences and opinions on heartwater incidence, distribution and associated factors in domestic ruminants in South Africa

Industry Sector: Cattle and Small Stock

Research Focus Area: Animal Health and Welfare

Research Institute: Faculty of Veterinary Science, University of Pretoria Department of Production Animal Studies

Researcher: Prof     Gareth Bath     ECSRHM

Title Initials Surname Qualification
Dr D Coetzee BVSc
Dr T Brink BVSc
Dr R Leask M. Med. Vet
Prof G Fosgate PhD

Year of completion : 2017

Aims Of The Project

  • To establish the extent and incidence of HW by a structured questionnaire sent to farmers and veterinarians in heartwater areas

  • To establish changes that may have occurred in these areas

  • To identify possible reasons for the changes observed.

  • To make recommendations for further action

Executive Summary

The Questionnaire Survey achieved the aims set out for the project. Sample sizes, structure, demographics, geographic distribution and experience profiles of both Veterinary and Farmer groups were adequate for gathering useful data and for conclusions to be drawn.

There appears to be epidemiologically significant change in the spatial distribution of heartwater in many areas, with serious expansion in some, of up to 150 kilometres, and 48% of veterinarians and 42% of farmers reported seeing increases in the number of farms affected by heartwater. The disease is also increasing in incidence and severity judging by the number of cases seen, increases in occurrence observed and also some indication that there is an increased risk of heartwater in more months of the year than in the past.

Climate change as a causative factor, indicated by observations of increased average temperatures, milder frosts, less rain and shorter rainy seasons, was identified by the majority of farmers but not by as many veterinarians. Respondents in both groups considered vegetation change an important factor. Increasing wildlife, especially antelope, was seen as a major factor by most veterinarians and also many farmers. Both groups identified the movement of livestock and wildlife as an increasingly important factor that must be seen as of major concern for both industries since it leads to the avoidable spread of many diseases apart from heartwater. Movement controls must be reinstated and reinforced by vigorously enforced legislation.

The use of the heartwater ‘vaccine’ is either unchanged or in decline and is apparently causing an increasing reliance on dipping and block treatments. Farmers reported mainly an increase in tick control by dipping and rated this as a very important factor in the management of heartwater; the veterinarians rated it lower. Control achieved by routine, regular block treatments of entire flocks or herds was also seen as a major factor and as increasing in use for both respondent groups, each giving it a high ranking. Relying on intensive tick control and ongoing block treatments leads to loss of efficacy in key acaricides and antibiotics and has very serious implications and consequences for the control of many diseases and parasites of livestock. The lack of a commercially available, safe, effective, practical and affordable true vaccine for the protection of ruminant livestock against heartwater should be of the absolute highest concern and priority. After decades of trials, OVI researchers have developed a very promising candidate vaccine, yet its further development to the commercial stage appears not to be receiving the urgency and attention needed.

Diagnosis of heartwater in post mortem cases is accurate and reliable if backed by appropriate histopathological staining and examination, but far too few farmers have their suspicions confirmed by laboratory tests. This leads to a danger of widespread misdiagnosis and the disease being potentially either under- or over-diagnosed. The problem extends to clinical cases especially, where diagnosis rests mainly on a few ‘typical’ signs. The presence of atypical forms of heartwater further complicates the problem.

Popular Article

Is Heartwater spreading and becoming worse, and why?

A survey of farmers and veterinarians in heartwater-prone areas of South Africa indicates that the disease is expanding in geographic area and increasing in severity. What are the possible reasons for this, what has changed in these areas, and what should be done to limit the impact of a worsening situation? The Heartwater Survey was undertaken by staff of the Faculty of Veterinary Science at Onderstepoort, and generously funded by the financial subvention of RMRD – SA.

A representative sample of veterinarians and farmers with adequate experience in areas where heartwater is a problem agreed to take part in the survey. The survey took the form of a structured, measureable and analysable set of questions in a standard questionnaire. The questionnaire was designed to allow comparisons to be made between the two groups, who were for the most part asked the same or similar questions. The responses of these two groups gave an insight into the current heartwater situation as it is experienced by the farmers and veterinarians in the heartwater areas, and shed some light on the importance of factors believed to be involved in the expansion of areas affected by heartwater and in the changes of its severity.

It was deduced from the responses of both groups that the disease is expanding its range in many areas, and alarmingly so – by an average of perhaps 60km and as much as 150 kilometres in some regions. The reports by both vets and farmers indicated that an increasing number of farms are becoming affected by heartwater, confirming that the disease appears to be spreading. It was also evident that annual losses caused by heartwater can be very high on some farms unless the disease is suppressed by unsustainable practices like intensive dipping or repeated blocking of entire herds and flocks with tetracycline antibiotics. Both groups also reported that the number of cases of heartwater is rising.

Several factors that were thought to be responsible for these changes were identified by the two groups, although they did not always agree on the relative importance of these factors. Climate change, evidenced by higher than average temperatures, milder frosts, lower rainfall and shorter rainy seasons, was seen as a major causative factor by most farmers but considered to be of less significance by the veterinarians. Both groups saw a change in vegetation as an important factor but more so by the vets, who also rated the role of increased wildlife and the movement of antelope as a major factor, more so than the opinion of the farmers. The groups were, however, in agreement about the important role played by the movement of livestock in the potential to increase the areas affected by heartwater.

The survey revealed that the use of the heartwater “vaccine” was stagnant or in decline, which is not surprising in view of the many difficulties encountered in its use, the risks and dangers inherent to it, and the uncertainties around its efficacy. Unfortunately this reluctance to use the vaccine has evidently led to an increasing use of frequent, suppressive tick control or reliance on regular blocking treatments for heartwater for entire herds or flocks. Neither of these control measures are sustainable in the long run, and are almost certain to hasten the onset and rapid development of drug resistance in the bont tick and the heartwater organism. It was also clear from the survey that the diagnosis and treatment of heartwater relies far too heavily on the clinical signs or symptoms seen, especially with the farmers, leading to the dangers of misdiagnosis.

In conclusion, the survey revealed that heartwater is increasing in both its geographic extent and its severity, at least in some areas, and that a number of factors appear to be involved in causing these changes. Chief of these were climate, vegetation, and wildlife and livestock movements. The role of static or declining vaccine usage, leading to an increased reliance on intensive tick control, or alternately the widespread use of whole herd blocking with tetracycline antibiotics was also revealed by the responses of both groups.

The most pressing need now to bring about satisfactory heartwater control is the rapid and prioritised development of a commercial vaccine by OBP that is safe, effective, practical, easy to use and affordable. This development can be based on the very promising candidate vaccine developed by OVI. Ensuring that the movement of both wildlife and livestock is properly controlled to try to reduce the spread of the disease is another priority requiring urgent attention.

Please contact the Primary Researcher if you need a copy of the comprehensive report of this project – Gareth Bath on gfbath@gmail.com