I found this - you can always try it, it doesn't sound like it will do any harm either way. (I wouldn't try the hanging upside down bit, just the yoghurt and garlic bit!)

I thought I would pass on some good advice that I was given recently from my local chicken supplier on the treatment of sour crop which was affecting one of our girls.

I noticed that her crop was enormous, about the size of a tennis ball when I let them all out one morning. When I picked her up her crop was full of fluid and made a sloshing sound when massaged. She still wanted to eat but seemed lethargic and moved her neck from side to side as if trying to shift or swallow something. I looked up the symptoms, on this site and identified it as sour crop which is a fungal infection of the crop. It recommended that I turn her carefully upside down and empty her crop of all the liquid and contents by massaging it. You need to do this fairly quickly to prevent her from choking and any fluid entering her lungs. When the crop is empty you will probably still feel some grit at the bottom. We then isolated her from the others and used a syringe with the end chopped off to feed her some natural live yoghurt (about 5ml - 10ml each time) three times a day for a couple of days but her crop still kept filling with fluid and I had to repeat the emptying process every morning. After speaking to our local chicken supplier he said that this treatment was good, however he recommended that we crush a couple of large cloves of raw garlic in a pestle and mortar into a couple of tablespoons of the live yoghurt and carry on the treatment. Garlic is anti-fungal and this made all the difference. Within a day her crop was much reduced in size and she was very hungry so we fed her light food, made-up porridge mixed with live yogurt and banana. After another day we put her back with the other girls while they were free ranging in the garden, to prevent her being picked on and thankfully all has been fine since. Now all we are waiting for is her to start laying again although the first eggs may well taste strongly of garlic! I hope this is of some help as I believe the garlic with the live yoghurt made all the difference.

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