Smell

[confederatemule]

How does a Chicken determine what to eat? Can they smell?

Thanks fer any answers.
Mule

 

[SunHwaKwon]

Yes, they can. My Evolution professor did all of his work on birds and their sense of smell and establishing evolutionary relationships based on olfactory development.

Generally, though, it seems they go more on sense of taste.

ETA. Here is the abstract of his primary paper, though I know it is hard to understand if you are not used to reading scientific publications. Contrary to what many people will say, olfactory abilities are not associated with the size of the (external) nose. After all, one creature may have a much smaller nose, in actual size and relative size, yet have a better sense of smell than another; this is akin to judging visual ability based on the size of eyes or sense of hearing based on external pinnae. For instance, a rat's nose is at best comparable to a dog's in size, yet their sense of smell is 50% better. What matters most is the number of olfactory receptors INSIDE the nose rather than the external appearance of the nose. It's hard to say with 100% certainty how well an animal smells, and studies use everything from receptors, the size of the olfactory bulb, presence of known genes, electrical impulses, behavior, etc to make their conclusions.

I'm sorry it copied and pasted so poorly.


The relative size of olfactory bulbs (OBs) is correlated with olfactory capabilities across
vertebrates and is widely used to assess the relative importance of olfaction to a
species’ ecology. In birds, variations in the r elative size of OBs are correlated with some
behaviors; however, the factors that have led to the high level of diversity seen in OB
sizes acr oss birds are still not well understood. In this study, we use the relative size
of OBs as a neuroanatomical proxy for olfactory capabilities in 135 species of birds,
representing 21 orders. We examine the scaling of OBs with brain size across avian
orders, determine likely ancestral states and test for correlations between OB sizes
and habitat, ecology, and behavior. The size of avian OBs varied with the size of the
brain and this allometric relationship was for the most part isometric, although species
did deviate from this trend. Large OBs were characteristic of more basal species and
in more recently derived species the OBs were small. Living and foraging in a semi-
aquatic environment was t he strongest v ariable driving the evolution of large OBs in
birds; olfaction may pr ovide cues for navigation and foraging in this otherwise featureless
environment. Some of the diversity in OB sizes was also undoubtedly due to differences
in migratory behavior, foraging strategies and social structure. In summary, relative
OB size in birds r eflect allometry, phylogeny and behavior in ways that parallel that
of other vertebrate classes. This provides comparative evidence that supports recent
experimental studies into avian olfaction and suggests that olfaction is an important
sensory modality for all avian species. (Diversity in Olfactory Bulb Size... 2015. Jeremy Corfield)

 

[azygous]

Both smell and sense of taste is limited in poultry mainly due to the size of the smell and taste receptors that have the capacity to send signals to the rather small brain.

You can generally judge the degree of smell and taste by observing the size of the nose. Birds have almost non-existent noses while dogs and bears have huge ones, hence a greater ability to differentiate a wide array of odors, as well as the ability to interpret what they mean. Humans have a very limited sense of smell compared to dogs and bears. We may smell something, but most of the time, we aren't able to judge what it means. Dogs not only smell things we can't, but are able to know the history of that smell and what the consequences are. It's like a sophisticated computer on their faces.

 

[confederatemule]

Thanks for responding.
Mule

 

[centrarchid]

Yes, they can. My Evolution professor did all of his work on birds and their sense of smell and establishing evolutionary relationships based on olfactory development.

Generally, though, it seems they go more on sense of taste.

ETA. Here is the abstract of his primary paper, though I know it is hard to understand if you are not used to reading scientific publications. Contrary to what many people will say, olfactory abilities are not associated with the size of the (external) nose. After all, one creature may have a much smaller nose, in actual size and relative size, yet have a better sense of smell than another; this is akin to judging visual ability based on the size of eyes or sense of hearing based on external pinnae. For instance, a rat's nose is at best comparable to a dog's in size, yet their sense of smell is 50% better. What matters most is the number of olfactory receptors INSIDE the nose rather than the external appearance of the nose. It's hard to say with 100% certainty how well an animal smells, and studies use everything from receptors, the size of the olfactory bulb, presence of known genes, electrical impulses, behavior, etc to make their conclusions.

I'm sorry it copied and pasted so poorly.


The relative size of olfactory bulbs (OBs) is correlated with olfactory capabilities across
vertebrates and is widely used to assess the relative importance of olfaction to a
species’ ecology. In birds, variations in the r elative size of OBs are correlated with some
behaviors; however, the factors that have led to the high level of diversity seen in OB
sizes acr oss birds are still not well understood. In this study, we use the relative size
of OBs as a neuroanatomical proxy for olfactory capabilities in 135 species of birds,
representing 21 orders. We examine the scaling of OBs with brain size across avian
orders, determine likely ancestral states and test for correlations between OB sizes
and habitat, ecology, and behavior. The size of avian OBs varied with the size of the
brain and this allometric relationship was for the most part isometric, although species
did deviate from this trend. Large OBs were characteristic of more basal species and
in more recently derived species the OBs were small. Living and foraging in a semi-
aquatic environment was t he strongest v ariable driving the evolution of large OBs in
birds; olfaction may pr ovide cues for navigation and foraging in this otherwise featureless
environment. Some of the diversity in OB sizes was also undoubtedly due to differences
in migratory behavior, foraging strategies and social structure. In summary, relative
OB size in birds r eflect allometry, phylogeny and behavior in ways that parallel that
of other vertebrate classes. This provides comparative evidence that supports recent
experimental studies into avian olfaction and suggests that olfaction is an important
sensory modality for all avian species. (Diversity in Olfactory Bulb Size... 2015. Jeremy Corfield)

Final sentence above seems to indicate sense smell can be important. When I get down and close to chickens foraging in soil they do appear to make sounds consistent will pulling air through nose in a manner that does not appear gear primarily towards breathing.

 

[GC-Raptor]

My raptors seem to use their eyes and hearing to find food. If they see me open the door where I keep the scratch grains, they come running. If they don't see me open the door, all I gotta do is shake the can, and they come running. similar to that guy, with their wings flapping. GC

 

[chickengeorgeto]

In my association with chickens and what they eat, it seems that chickens depend more on trial and error otherwise known as past association when deciding what to eat and what not to eat.

I am basing this on the fact that when I received a free truck load of Indian corn that most of the colorful grains of corn laid on the ground for up to a week before my hens decided that they were eatable. After they made that discovery the red, blue, orange, or other colored corn grains began disappearing into their crops like plain old everyday yellow dent corn did. There was also a significant difference in the size and shape of yellow field corn compared to Indian corn.

The next time that you hatch off a clutch of chicks try this. Don't feed the biddies at first but put newspaper down like you would in a birds' cage. I'll bet that the chicks will attempt to eat the news print off the news paper. News print in no way taste, or smells like chicken feed although I will admit that newsprint may contain some soybean oil.

 

[Chickassan]

They will try and eat the newsprint, I lined my brooder pen with salespapers and junk mail they definitely tried to eat it. Might have been because i promised treats to whoever pooped on the celebrities when I used the enquirer but I'll go with the more scientific reasoning.

In my association with chickens and what they eat, it seems that chickens depend more on trial and error otherwise known as past association when deciding what to eat and what not to eat.

I am basing this on the fact that when I received a free truck load of Indian corn that most of the colorful grains of corn laid on the ground for up to a week before my hens decided that they were eatable. After they made that discovery the red, blue, orange, or other colored corn grains began disappearing into their crops like plain old everyday yellow dent corn did. There was also a significant difference in the size and shape of yellow field corn compared to Indian corn.

The next time that you hatch off a clutch of chicks try this. Don't feed the biddies at first but put newspaper down like you would in a birds' cage. I'll bet that the chicks will attempt to eat the news print off the news paper. News print in no way taste, or smells like chicken feed although I will admit that newsprint may contain some soybean oil.