Thank you for your patience. This little girl looks to be around 12 - 16 weeks just from judging her size. It is quite likely that she is feral, but there is a small chance she is owned and has managed to go missing from her regular home. Just in case, it would be a wise idea to have your local vet check for a microchip. There are a number of reasons as to why this girl could be vomiting including anything from a nasty gastroenteritis, to a feline virus like panleukopenia, to intestinal parasites, or even due to trauma from being up in wheel space of the truck. It is also a concern that she doesn't seem to be peeing or pooping at this stage. Make sure you have a litter box or two available for her, and try a couple of different litter types (paper pellets in one and clay based litter in the other for example). Feeding a kitten food (wet food is possible) and encouraging her water intake here will help, but if she is vomiting everything she eats/drinks, then it could simply be that she is actually constipated.
Because of the nature of how you found her, and because we need to rule out whether she has a microchip, it would be a good idea to get her seen by your local vet today if you can. Here they can carry out a full physical exam, give her some deworming medication and check for a microchip. Giving her an anti-nausea injection may also help to settle this vomiting, and if this girl is dehydrated, then they may need to start her on some intravenous fluids.
If you can't get her seen today, then for now encourage her to drink plenty of water, and offer food in small amounts frequently, rather than 2 large meals. If you can source, please also get some deworming medication for this girl. The reliable all-wormers are 'drontal', 'milbemax' and 'panacur' and you may be able to get these over the counter from your local vet. If this girl continues to vomit and can't keep water down, then she will likely very quickly become dehydrated. For this reason - do get her seen today if this is the case here. For now please also keep an eye on Lunas mucus membranes, capillary refill time and respiratory rate as follows (do be careful that your girl doesn't try to bite you):
Mucus membranes - flip her lip and look at the color of her gums. They should maintain a nice salmon pink color. Get her to the emergency Vet if they appear white or very pale pink, or if they are a dark deep red color.
Capillary Refill time - this measures blood perfusion and test this by putting your thumb on her gum to apply pressure. After you release your thumb you will see the gum blanch. Capillary refill time is the amount of time it takes (in seconds) for the gum to return to a healthy pink color from the blanched white color. If 2 seconds or less don't worry - if it is taking significantly more time, again - off to the emergency Vet.
Respiratory Rate - if she is continuously panting or open mouth breathing at all tonight, this is a sign of shock and or pain and a signal for a trip to the emergency Vet.
Best of luck with Luna, and as above - you will need to get her to your local vet either today or tomorrow morning for a full check over, deworming and a check for a microchip. Once her vomiting has settled and she has improved, then she can have her first vaccination (which is very important). I hope all of the above makes sense? Please let me know if you have any other questions. My goal is to provide you with excellent service – if you feel you have gotten anything less, please reply back. I am happy to address follow-up questions. Thank you for your business and I hope to work with you again soon!
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