- MeSH A13 – animal structures
- MeSH A13.048 – air sacs
- MeSH A13.073 – anal sacs
- MeSH A13.114 – beak
- MeSH A13.163 – bursa of fabricius
- MeSH A13.223 – cloaca
- MeSH A13.242 – comb and wattles
- MeSH A13.250 – corpora allata
- MeSH A13.265 – crop, avian
- MeSH A13.316 – egg shell
- MeSH A13.332 – electric organ
- MeSH A13.350 – embryo, nonmammalian
- MeSH A13.350.150 – chick embryo
- MeSH A13.350.575 – chorioallantoic membrane
- MeSH A13.365 – fat body
- MeSH A13.370 – feathers
- MeSH A13.395 – forelimb
- MeSH A13.395.248 – carpus, animal
- MeSH A13.395.823 – wing
- MeSH A13.408 – ganglia, invertebrate
- MeSH A13.421 – gills
- MeSH A13.445 – harderian gland
- MeSH A13.453 – hemolymph
- MeSH A13.463 – hepatopancreas
- MeSH A13.473 – hindlimb
- MeSH A13.473.683 – stifle
- MeSH A13.473.821 – tarsus, animal
- MeSH A13.491 – hoof and claw
- MeSH A13.507 – horns
- MeSH A13.507.288 – antlers
- MeSH A13.530 – interrenal gland
- MeSH A13.574 – malpighian tubules
- MeSH A13.589 – mammary glands, animal
- MeSH A13.600 – metrical gland
- MeSH A13.641 – mushroom bodies
- MeSH A13.660 – nictitating membrane
- MeSH A13.686 – optic lobe
- MeSH A13.706 – oviducts
- MeSH A13.706.500 – fallopian tubes
- MeSH A13.734 – perianal glands
- MeSH A13.750 – photoreceptors, invertebrate
- MeSH A13.811 – salt gland
- MeSH A13.820 – scent glands
- MeSH A13.853 – stomach, avian
- MeSH A13.853.363 – gizzard
- MeSH A13.853.710 – proventriculus
- MeSH A13.869 – stomach, ruminant
- MeSH A13.869.106 – abomasum
- MeSH A13.869.524 – omasum
- MeSH A13.869.697 – reticulum
- MeSH A13.869.804 – rumen
- MeSH A13.895 – tail
- MeSH A13.939 – ultimobranchial body
- MeSH A13.950 – vibrissae
- MeSH A13.970 – wool
- MeSH A13 – animal structures
- MeSH A13.048 – air sacs
- MeSH A13.073 – anal sacs
- MeSH A13.114 – beak
- MeSH A13.163 – bursa of fabricius
- MeSH A13.223 – cloaca
- MeSH A13.242 – comb and wattles
- MeSH A13.250 – corpora allata
- MeSH A13.265 – crop, avian
- MeSH A13.316 – egg shell
- MeSH A13.332 – electric organ
- MeSH A13.350 – embryo, nonmammalian
- MeSH A13.350.150 – chick embryo
- MeSH A13.350.575 – chorioallantoic membrane
- MeSH A13.365 – fat body
- MeSH A13.370 – feathers
- MeSH A13.395 – forelimb
- MeSH A13.395.248 – carpus, animal
- MeSH A13.395.823 – wing
- MeSH A13.408 – ganglia, invertebrate
- MeSH A13.421 – gills
- MeSH A13.445 – harderian gland
- MeSH A13.453 – hemolymph
- MeSH A13.463 – hepatopancreas
- MeSH A13.473 – hindlimb
- MeSH A13.473.683 – stifle
- MeSH A13.473.821 – tarsus, animal
- MeSH A13.491 – hoof and claw
- MeSH A13.507 – horns
- MeSH A13.507.288 – antlers
- MeSH A13.530 – interrenal gland
- MeSH A13.574 – malpighian tubules
- MeSH A13.589 – mammary glands, animal
- MeSH A13.600 – metrical gland
- MeSH A13.641 – mushroom bodies
- MeSH A13.660 – nictitating membrane
- MeSH A13.686 – optic lobe
- MeSH A13.706 – oviducts
- MeSH A13.706.500 – fallopian tubes
- MeSH A13.734 – perianal glands
- MeSH A13.750 – photoreceptors, invertebrate
- MeSH A13.811 – salt gland
- MeSH A13.820 – scent glands
- MeSH A13.853 – stomach, avian
- MeSH A13.853.363 – gizzard
- MeSH A13.853.710 – proventriculus
- MeSH A13.869 – stomach, ruminant
- MeSH A13.869.106 – abomasum
- MeSH A13.869.524 – omasum
- MeSH A13.869.697 – reticulum
- MeSH A13.869.804 – rumen
- MeSH A13.895 – tail
- MeSH A13.939 – ultimobranchial body
- MeSH A13.950 – vibrissae
- MeSH A13.970 – wool