Predictors of dead on arrival (DOA) among broilers slaughtered at a poultry abattoir in Mopani District of Limpopo Province, South Africa

Abstract

Dead-on-arrival (DOA) at poultry abattoirs is a significant problem faced by poultry producers and abattoirs and causes losses of billions of rands each year. However, the phenomenon of DOAs has not been extensively investigated in South Africa. The aim of this study was to investigate the trend in the proportions of DOAs and factors associated with DOA counts among chickens slaughtered at a commercial abattoir in the Mopani district in Limpopo, South Africa. In this study, secondary data of broilers slaughtered at an abattoir between January 2014 and December 2016 was used to assess the temporal trend of DOA counts and factors associated with DOA counts. A negative binomial model was fit to the data to investigate the association between predictor variables (i.e., years, seasons, biosecurity, capacity, distance travelled, birds’ average mass and farm rejected) and the outcome variable (DOA counts). The percentage of DOA counts recorded over the study period was 0.48%. The highest proportion of DOAs were observed during the summer months (0.77%; 95% CI: 0.7695 - 0.7789) followed by spring (0.41; 95% CI: 0.4082-0.4179), autumn (0.41%; 95% CI: 0.4069-0.4165) and winter months (0.26%; 95% CI: 0.2614- 0.2667). The live mass (Kg) of birds (IRR=5.706; 95CI: 3.696- 8.738), the number of birds rejected at farm level (IRR= 3.66; 85% CI: 2.437- 5.596), summer season (IRR= 1.873; 95% CI: 1.552- 2.60) and years (IRR=1.742; 95% CI: 1.486- 2.042) were significant predictors of DOA counts. The percentage of birds that were DOA in this study was low and decreased over the study period. The potential predictors of DOA counts identified in this study can be useful in guiding abattoirs and poultry farmers in managing broilers on farms, during catching, transportation and while in the lairage so as to minimize the DOA counts. Given the limited nature of this study in that it involved only one abattoir, there is a need for larger studies involving more abattoirs and farms to confirm the findings reported in this study.

Dooie-by-aankoms (DOA) by pluimvee-abattoirs is 'n belangrike probleem waarmee pluimveeprodusente en abattoirs te kampe het, en dit lei jaarliks tot verliese van miljarde rande. Die verskynsel van DOA's is egter nie breedvoerig in Suid-Afrika ondersoek nie. Die doel van hierdie studie was om die tendens te ondersoek in die verhoudings van DOA's en faktore wat verband hou met DOA-tellings onder hoenders wat by 'n kommersiële slagpale in die Mopani-distrik in Limpopo, Suid-Afrika, geslag is. In hierdie studie is sekondêre data van braaikuikens wat tussen Januarie 2014 en Desember 2016 by 'n abattoir geslag is, gebruik om die tydelike neiging van DOA-tellings en faktore wat verband hou met DOA-tellings te beoordeel. 'N Negatiewe binomiale model was geskik vir die data om die verband tussen voorspellingsveranderlikes (d.w.s. jare, seisoene, biosekuriteit, kapasiteit, afstand afgelê, gemiddelde massa van voëls en plaasverwerping) en die uitkomsveranderlike (DOA-tellings) te ondersoek. Die persentasie DOA-tellings wat gedurende die studietydperk aangeteken is, was 0,48%. Die hoogste persentasie DOA's is waargeneem gedurende die somermaande (0,77%; 95% KI: 0,7695 - 0,7789) gevolg deur die lente (0,41; 95% KI: 0,4082-0,4179), herfs (0,41%; 95% KI: 0,4069-0,4165 ) en wintermaande (0,26%; 95% BI: 0,2614- 0,2667). Die lewende massa (Kg) van voëls (IRR = 5,706; 95CI: 3,696- 8,738), die aantal voëls wat op plaasvlak afgekeur is (IRR = 3,66; 85% BI: 2,437 - 5,596), somerseisoen (IRR = 1,873; 95 % GI: 1,552-2,60) en jare (IRR = 1,742; 95% GI: 1,486-2,042) was beduidende voorspellers van DOA-tellings. Die persentasie voëls wat DOA was in hierdie studie was laag, maar het gedurende die studietydperk afgeneem. Die potensiële voorspellers van DOA-tellings wat in hierdie studie geïdentifiseer is, kan nuttig wees om slagplase en pluimveeboere te begelei in die bestuur van braaikuikens op plase, tydens die vang, vervoer en in die laer om sodoende die DOA-tellings te verminder. Gegewe die beperkte aard van hierdie studie deurdat dit slegs een slagplaas behels, is daar 'n behoefte aan groter studies wat meer slagplase en plase betrek om die bevindinge wat in hierdie studie gerapporteer is, te bevestig.

Ukufika-ekufikeni (i-DOA) kwizilarha zeenkukhu yingxaki ebalulekileyo abajongana nayo abavelisi beenkukhu kunye nezilarha zokuxhela kwaye ibangela ilahleko yeebhiliyoni zeerandi ngonyaka. Nangona kunjalo, imeko ye-DOAs khange iphandwe ngokubanzi eMzantsi Afrika. Injongo yolu phononongo yayikukuphanda imeko kumlinganiso we-DOAs kunye nezinto ezinxulumene nokubalwa kwe-DOA phakathi kweenkukhu ezixheliweyo kwindawo yokuxhela kurhwebo kwisithili seMopani eLimpopo, eMzantsi Afrika. Kolu phononongo, idatha yesibini yeenkuku ezixheliweyo kwindawo yokuxhela phakathi kukaJanuwari 2014 noDisemba 2016 yayisetyenziselwa ukuvavanya imeko yexeshana yokubalwa kwe-DOA kunye nezinto ezinxulumene nokubalwa kwe-DOA. Imodeli engalunganga yokulinganisa ibifanele idatha yokuphanda unxibelelwano phakathi kwezinto ezixeliweyo (okt, iminyaka, amaxesha, ukhuseleko, amandla, umgama ohanjiweyo, ubunzima beentaka kunye nefama eyaliwe) kunye nesiphumo esiguqukayo (ukubalwa kwe-DOA). Umyinge wezibalo ze-DOA ezirekhodwe ngexesha lokufunda yayiyi-0.48%. Elona nani liphezulu le-DOAs laqwalaselwa ngeenyanga zehlobo (0.77%; 95% CI: 0.7695 - 0.7789) kulandelwa intwasahlobo (0.41; 95% CI: 0.4082-0.4179), ekwindla (0.41%; 95% CI: 0.4069-0.4165 ) kunye neenyanga zasebusika (0.26%; 95% CI: 0.2614- 0.2667). Ubunzima obuphilayo (Kg) beentaka (IRR = 5.706; 95CI: 3.696- 8.738), inani leentaka ezaliwe kwinqanaba lefama (IRR = 3.66; 85% CI: 2.437- 5.596), ixesha lehlobo (IRR = 1.873; 95 % CI: 1.552- 2.60) kunye neminyaka (IRR = 1.742; 95% CI: 1.486- 2.042) babengabalulekanga ababalulekileyo be-DOA. Ipesenti yeentaka ezaziyi-DOA kolu phando yayisezantsi kodwa yehla ngexesha lokufunda. Uqikelelo olunokubakho lobalo lwe-DOA oluchongiweyo kolu phando lunokuba luncedo ekukhokeleni izilarha kunye neefama zeenkukhu ekulawuleni iinkuku zenyama kwiifama, ngexesha lokuloba, ukuthuthwa naxa kuselwandle ukuze kuncitshiswe ukubalwa kwe-DOA. Ngenxa yokunqongophala kolu phando kuba luchaphazela isilarha esinye kuphela, kukho imfuneko yezifundo ezikhulu ezibandakanya izilarha kunye neefama ezininzi ukuqinisekisa iziphumo ezixeliweyo kolu phando.