How can we help you?

Stocking density can influence SE susceptibility in laying hens

Higher stocking density can render layer hens more susceptible to Salmonella Enteritidis (SE), according to a report in Poultry Science.¹

In two trials, the researchers placed groups of laying hens at two different stocking densities into colony cages. One group consisted of 40 hens housed 20 per cage at a stocking density of 973 cm² (1.04733 sq. ft.) floor space per bird, and the other group consisted of 60 hens housed 30 per cage at a stocking density of 648 cm² (0.697501 sq. ft.) floor space per bird. The investigators orally inoculated the birds with SE and then cultured internal organs 5 to 6 days later.

Significantly more SE (p < 0.05) was recovered from livers (75% versus 51.4%) and ovaries (51.4% versus 30.6%) of hens from the higher-density group, according to investigators from USDA’s Agricultural Research Service and North Carolina State and Michigan State universities.

However, they also found that spleens from hens in the higher-density colony cages were significantly (p = 0.0018) less often positive for SE compared to hens in conventional cages that were also challenged with SE but housed at the same density — 90.3% versus 68.1%.

Although stocking density can influence hens’ SE susceptibility, other housing system parameters might contribute to the outcome of infections, the investigators concluded.

¹Gast R, et al. Colonization of internal organs by Salmonella Enteritidis in experimentally infected laying hens housed in enriched colony cages at different stocking densities. Poult Sci. 2016; 95:1363-1369.