There are no regular hens anymore! That's kinda the point. Every supermarket supplying hen is producing far more eggs than their non purpose-bred ancestors would.
The broken bones are not even visible, their behavior change is very subtle. You'd have to x-ray the hens to see the damage.
Here [0] is a report from Switzerland (in German) saying that 97% of egg laying hens in Switzerland have on average 3 broken bones, some even as much as 11.
Ethical eg farming using current hen races is simply impossible.
That report seems very high, here's a similar study in England that looks at the bones of end-of-lay hens that are culled and 14% of free range chickens have fractures, some of which they cannot guarantee were not from the transport/handling as part of the study. Assume worst case, that's 14% of hens with fractures. Conventional cages have 31% fractures. Of those fractures, keel bone fractures from bumping into the hen house furniture is the most likely reason, but also badly designed perches injuring the knees. Interestingly the reason why fractures may be increasing is because moving from conventional cages to hen houses increase bumping into things and breaking bones (point 57).
> Every supermarket supplying hen is producing far more eggs than their non purpose-bred ancestors would
The fractures seem to be mostly unrelated to the number of eggs laid in this study.
> There are no regular hens anymore! That's kinda the point.
Either way, at least there's pressure on farming bodies to avoid all fractures so hopefully this isn't an issue for long.
Your 14% figure stems from a single study, precisely the oldest study mentioned on the report linked, while three paragraphs down it mentions the newest study, quote:
"The most recent results (University of Bristol; Defra project AW0234), from a
survey of 67 flocks (not including conventional cages) were similar but even worse,
particularly because only keel bone fractures were recorded. Thirty six per cent of
hens from enriched cages had fractures (of the keel bone) and the average
prevalence in other non-cage systems ranged from 45 to 86%. In the worst flocks,
95% of hens had fractured keel bones." (Emphasis mine.)
The report I linked even says that the old results massively under estimate bone fractures because they seldomly used x-rays to find them!
And not only that, your 14% figure are the new fractures, i.e. the ones that did not occur during laying! One newer study from 2006, mentioned in your report just two paragraphs after the one you got your figure from, estimates these old fractures of free range hens at 44%!
> The fractures seem to be mostly unrelated to the number of eggs laid in this study.
Even that is explicitly contradicted by your report, quote:
"Osteoporosis is further exacerbated by the great egg output of modern
hybrids. In 1930, a hen laid around 115 eggs in a laying cycle (from about 20 to 72
weeks of age) but nowadays a hen lays around 300 eggs, almost an egg per day for
a year. A hen’s need for calcium for eggs exceeds her body reserves by about 30
times."
Please, actually be honest on offering a counterpoint.
The broken bones are not even visible, their behavior change is very subtle. You'd have to x-ray the hens to see the damage.
Here [0] is a report from Switzerland (in German) saying that 97% of egg laying hens in Switzerland have on average 3 broken bones, some even as much as 11.
Ethical eg farming using current hen races is simply impossible.
[0] https://www.luzernerzeitung.ch/wirtschaft/neue-studie-roentg...