Help please - identifying a problem with a young geese

[Karen___]

Hello everyone,

This is my first time raising waterfowl. About 4 weeks ago I got 6 little goslings, 3 Toulouse and 3 Africans. They stayed inside my house for the first week then I arranged them a little house outside with a grazing pad. Everything was going well until a few days ago. One of the African gosling started losing down on the top of his head. All the others are normal. I thought it might be due to heat stress, we have been having very warm weather here in the last few days. They have access to a shaded area and water in their pen, so I added a small water pool and a fan. However today when I went to check on him I noticed that he also started losing down on his neck and that his newest feathers are not developing properly. The down is not entirely gone, there is still a layer but it is shorter and more sparse then on the rest of his body. He started growing feathers a little while ago, but the newest ones at the ends of his wings seem to lack the feathery part and I can only see little quills.

Apart from this, he seems happy and healthy, but I am worried. He eats and drinks water and nibbled my pants while I was trying to check him. All the goslings stay outside in the day and have access to pasture. In the evening I bring them back to their house and lock them up, feeding them a bit of grain. I add vitamins to their water once a day and change their water three times a day. I couldn't find anything information relating to this on the internet. I will try to take a picture later and post it, but if anyone has ideas on what it could be it would be very welcome!

 

[azygous]

Waiting for a photo depicting what you've described.

 

[Karen___]

Here are photos, I've highlighted the areas with the symptoms, thank a lot!

 

[Eggcessive]

Could the others be pecking his feathers? Is he the meekest one? Make sure they have plenty of room. What are you feeding them?

 

[azygous]

I see pin feathers in the spots that concern you. I think you're concerned because this particular gosling is a bit slow to grow out the pin feathers compared to its mates. Genetics perform a role in how quickly a bird feathers out. Some individuals lag behind the others, but from what I'm seeing in your excellent photos is there is little to worry about. This youngster will catch up and have a set of gorgeous feathers in no time.

 

[Karen___]

A big thanks for the quick answers! It's a good thing if he's fine and I'm just worrying too much : )
A few more precisions to answer Eggcessive's reply :
He is a tad smaller than the others. He is also the friendliest one and often comes first to see me when I enter the pen. So far I've never seen them pecking each others plumage. I fed them non-medicated chicken starter feed at 24% for 3 weeks and since a week ago I mix it incrementally with chicken grower feed at 17% protein. Right now I'm at a half-half ratio. I give them one peanut butter jar (of the 1kg size) every evening when I take them to their house. During the day they eat grass and a variety of weeds growing in the pasture. The pen is about 20 ft by 10ft and I've been moving it around the yard every 2-3 days. Their house for the night is about 6 ft by 4 ft. The bedding is straw but I'm changing it today to wood shavings since I read while looking up for something matching the symptoms I saw that straw can foster diseases.