Factors associated with pre-slaughter mortality in turkeys and end of lay hens

Abstract

Pre-slaughter transportation may affect poultry welfare and mortality rates. A retrospective analysis was conducted to examine the effect of environmental, management and individual factors on the percentage of dead birds during pre-slaughter transportation (dead-on-arrival, DOA). The variables accounted for in the analyses included: environmental temperature, travel duration, genetic line, gender, crate type and crate stocking density. Among the 41 452 loads of turkeys (34 696 388 birds) and 3241 of end of lay hens (21 788 124 birds) transported to three large abattoirs in northern Italy in a 3-year period, the median DOA was 0.14% in turkeys, and 0.38% in hens. In turkeys, travel duration longer than 30 min, temperature higher than 26°C and high in-crate densities were associated with increased DOA. In winter (⩽2°C), high stocking densities did not reduce the mortality risk from cold stress; on the contrary, for stocking densities either near to or just above the maximum density in EC Reg. 1/2005, the DOA risk was greater than for loads with densities of 10 kg/m2 less than the EC maximum. Male birds and specific genetic lines also showed a higher DOA. In hens, transportation lasting longer than 2 h and the brown-feathered breed were associated with higher DOA. Dead-on-arrival progressively increased with travel duration, remaining constant between 4 and 6 h and peaking at 8 h (median: 0.57%). The maximum DOA increase was detected during winter. These results show that several species-specific factors may lead to increased risk of mortality.

Effects of Season, Plumage Colour, and Transport Distance on Body Weight Loss, Dead-on-Arrival, and Reject Rate in Commercial End-of-Lay Hens

“…This could be caused by challenging climate conditions in Turkey and may be due to longer transport distances. Previous studies also found a higher mortality rate in cold seasons [ 5 , 12 , 16 , 25 ].…”

“…The negative effect of longer transport distances on poultry welfare was also shown in previous studies. Many previous studies on end-of-lay hens found that longer transportation distances increase the mortality rate of animals [ 5 , 9 , 12 , 16 ]. The DOA rate in the current study was higher than in previous studies because the hens in this study were transported longer distances and might have faced harder climate conditions than those of previous studies.…”

“…Another study [ 15 ] analysed data of the same country (the Czech Republic) from the years 1997–2006 and found the dead-on-arrival rate (DOA) to be 1.013% during the transport of hens and cockerels. De Martino et al [ 16 ] analysed the data of 21.7 million hens transported for slaughter between 2010 and 2012 in Italy and found the median value of DOA to be 0.38%. Furthermore, the same study found that the rate of DOA increases in the winter season; with longer transportation distances, brown-feathered birds had a higher rate of DOA.…”

Antimicrobial Use in Broilers Reared at Different Stocking Densities: A Retrospective Study

“…Furthermore, footpad lesions are reported to be strongly related to litter moisture and season, rather than SD per se [ 19 ]. Finally, the threshold for DOA does not reflect average values (around 0.33%) [ 20 ] and is influenced by transport condition, rather than by the husbandry system itself [ 21 ]. No threshold for AMU is currently set by health authorities in relationship with SD, and it cannot be excluded that a higher AMU is needed to keep mortality and footpad lesions under control, as they are partly determined by enteric dysbiosis that worsen litter quality [ 22 ].…”

Assigning Defined Daily/Course Doses for Antimicrobials in Turkeys to Enable a Cross-Country Quantification and Comparison of Antimicrobial Use

“…However, these differences are difficult to interpret due to dissimilarities in used methodologies. Knowing that turkeys have a higher predisposition for disease and a longer production cycle, leading to build-up of litter or more environmental stressors, a higher AMU in turkeys compared to broilers is expected [16,[37][38][39].…”