The series of processes by which an animal acquires, processes, digests, absorbs, metabolizes, and excretes portions of its external chemical environment for the function of internal metabolism

Any chemical element or compound in the diet that supports normal reproduction, growth, lactation, or maintenance of life processes

(primary producers) • Plants, algae, phytoplankton

Produce complex organic compounds from simple inorganic molecules and energy from light (photosynthesis

(consumers) • E.g., animals, etc. • Require food to supply energy and nutrients

The series of processes by which an animal acquires, processes, digests, absorbs, metabolizes, and excretes portions of its external chemical environment for the function of internal metabolism

Any chemical element or compound in the diet that supports normal reproduction, growth, lactation, or maintenance of life processes

(primary producers) • Plants, algae, phytoplankton

Produce complex organic compounds from simple inorganic molecules and energy from light (photosynthesis

(consumers) • E.g., animals, etc. • Require food to supply energy and nutrients

The series of processes by which an animal acquires, processes, digests, absorbs, metabolizes, and excretes portions of its external chemical environment for the function of internal metabolism

Any chemical element or compound in the diet that supports normal reproduction, growth, lactation, or maintenance of life processes

(primary producers) • Plants, algae, phytoplankton

Produce complex organic compounds from simple inorganic molecules and energy from light (photosynthesis

(consumers) • E.g., animals, etc. • Require food to supply energy and nutrients

It means that animals in stable conditions will eat some foods that are outside their natural diet to acquire the nutrients that they need

It means that animals in harsh conditions will eat some foods that are outside their natural diet to acquire the nutrients that they need

It means that animals will completely swap over do a different diet within harsh conditions to beat out competition

Predominantly eats plant matter to reach their dietary and energy needs, with on the very rare occasion during harsh conditions consuming meat

Will eat anything, they have the ability to digest such and their dietary and nutritional needs come from a balance of both plant and meat matter

Predominantly eats meat matter to reach their dietary and energy needs, with on the very rare occasion during harsh conditions consuming plants

Predominantly eats plant matter to reach their dietary and energy needs, with on the very rare occasion during harsh conditions consuming meat

Will eat anything, they have the ability to digest such and their dietary and nutritional needs come from a balance of both plant and meat matter

Predominantly eats meat matter to reach their dietary and energy needs, with on the very rare occasion during harsh conditions consuming plants

Predominantly eats plant matter to reach their dietary and energy needs, with on the very rare occasion during harsh conditions consuming meat

Will eat anything, they have the ability to digest such and their dietary and nutritional needs come from a balance of both plant and meat matter

Predominantly eats meat matter to reach their dietary and energy needs, with on the very rare occasion during harsh conditions consuming plants

Food of animal origin

Rich in nutrients

Easy to digest/absorb

Usually hard to catch

Requires energy

Less abundant

Often ingest at intervals

Food of plant origin

Generally bulky

Typically abundant and easy to obtain

May have large undigestible components

Diverse in chemical and nutritional composition

Food of animal origin

Rich in nutrients

Easy to digest/absorb

Usually hard to catch

Highly selective diet, simple gut, rapid transit

Less selective, more complicated slow transit

Food of plant origin

Generally bulky

Typically abundant and easy to obtain

May have large undigestible components

Diverse in chemical and nutritional composition

Food abundance

Food quality

Nutrient requirements

Food taste

Food options

Direct observation

Feeding site surveys

Post ingestion sampling

Biological indicators

Stable isotopes and signatures of specific nutrients

Feed Testing

Pro: Real time recorded media

Cons: Time consuming, limited/biased observation

Pro: Clip patches of randomly selected areas

Con: Must mimic animal selectively

Ex: Fistula, gavage, fecal, post-mortem

Cons: Invasive, requires refence collection. ID keys,

for fecal only most resistant items are present, most digested, need additional molecular techniques

Pro: Real time recorded media

Cons: Time consuming, limited/biased observation

Pro: Clip patches of randomly selected areas

Con: Must mimic animal selectively

Ex: Fistula, gavage, fecal, post-mortem

Cons: Invasive, requires refence collection. ID keys,

for fecal only most resistant items are present, most digested, need additional molecular techniques

Pro: Real time recorded media

Cons: Time consuming, limited/biased observation

Pro: Clip patches of randomly selected areas

Con: Must mimic animal selectively

Ex: Fistula, gavage, fecal, post-mortem

Pro: Will find which plant matter is consumed C3 vs C4 and position on food chain

Cons: Invasive, requires refence collection. ID keys,

for fecal only most resistant items are present, most digested, need additional molecular techniques

Carbohydrates and Proteins

Lipids and Vitamins

Minerals and Water

Electrolytes and Iron

Energy

The defined level of a particular nutrient required to support the maintenance of life processes (and growth, reproduction, lactation, if applicable)

Required in the diets

Cannot be synthesized by the body in sufficient amounts (or at all) to satisfy metabolic needs

The defined level of a particular nutrient required to support the maintenance of life processes (and growth, reproduction, lactation, if applicable)

Required in the diets

Cannot be synthesized by the body in sufficient amounts (or at all) to satisfy metabolic needs

The (bio)chemical and physical characteristics of the food items matter, not necessarily the food items themselves

-

Lethargy

Death

Failure to maintain BW (Emaciation)

Stunted growth

Failure to reproduce

Decreased production of nutrients in the body

Poor chemical compound production

Bodily growth/regeneration/maintanance

Provide energy

Regulate chemical processes

Only for bodily growth/maintanance

Only for chemical proccesses

Species/breed

Sex

Size of species

Genetic Variation

Housing Condition

Age/Life Stages

Exercise Level

BW and Body condition

Species/breed

Sex

Size of species

Genetic Variation

Housing Condition

Age/Life Stages

Exercise Level

BW and Body condition

Species/breed

Sex

Size of species

Genetic Variation

Housing Condition

Age/Life Stages

Exercise Level

BW and Body condition

Were originally one species that moved amongst the carious islands of the Galapagos

Given the different environments of the islands they offered different food sources and niches for the birds to occupy

Overtime the same species bird evolved to have different beak shapes and different dietary focuses

They had evolved to grow longer necks given that their food source was so high, so the shorter necked giraffes became the long necked giraffes

It was eventually due to natural selection where the giraffes with the longer necks were able to survive and reproduce more successfully than the short necked giraffes

Were originally one species that moved amongst the carious islands of the Galapagos

Given the different environments of the islands they offered different food sources and niches for the birds to occupy

Overtime the same species bird evolved to have different beak shapes and different dietary focuses

They had evolved to grow longer necks given that their food source was so high, so the shorter necked giraffes became the long necked giraffes

It was eventually due to natural selection where the giraffes with the longer necks were able to survive and reproduce more successfully than the short necked giraffes

Share a similar structure on overall GIT

Species specific adaptations reflecting their unique dietary niche

Headgut -> Foregut -> Hindgut -> Midgut

Headgut -> Midgut -> Foregut -> Hindgut

Headgut -> Foregut -> Midgut -> Hinddgut

Foregut -> Headgut -> Hindgut -> Midgut

Prehension (Grabbing)

Ingestion

Mastication (Chewing)

Deglutition (Swallowing)

Digestion (Mechanical, chemical, enzymatic)

Absorption

Metabolism

Excretion

Filtration

Compound Production

Buccal Cavity and Pharynx

Including lips, cheeks, teeth hard and soft palates, tongue and salivary glands

Esophagus and Stomach

Small intestine (Duodenum, Jejunum, Ileum)

Pancreas and biliary system

Large intestine

(Cecum/ceca, colon, and rectum)

Buccal Cavity and Pharynx

Including lips, cheeks, teeth hard and soft palates, tongue and salivary glands

Esophagus and Stomach

Small intestine (Duodenum, Jejunum, Ileum)

Pancreas and biliary system

Large intestine

(Cecum/ceca, colon, and rectum)

Buccal Cavity and Pharynx

Including lips, cheeks, teeth hard and soft palates, tongue and salivary glands

Esophagus and Stomach

Small intestine (Duodenum, Jejunum, Ileum)

Pancreas and biliary system

Large intestine

(Cecum/ceca, colon, and rectum)

Buccal Cavity and Pharynx

Including lips, cheeks, teeth hard and soft palates, tongue and salivary glands

Esophagus and Stomach

Small intestine (Duodenum, Jejunum, Ileum)

Pancreas and biliary system

Large intestine

(Cecum/ceca, colon, and rectum)

Foregut: They ferment their food in their stomach, feed the bacteria first, and their stomachs have multiple compartments

Hindgut: They ferment their food in their large intestine, feed themselves first, and have very simple stomachs

Foregut: They ferment their food in their large intestine, feed themselves first, and have very simple stomachs

Hindgut: They ferment their food in their stomach, feed the bacteria first, and their stomachs have multiple compartments

Plant fiber is resistant to autoenzymatic digestion (digestive enzymes secreted by the host/animals themselves)

Therefore, requiring alloenzymatic digestion (enzymes produced from symbiotic microorganisms)

Therefore, requiring autoenzymatic digestion (enzymes produced from symbiotic microorganisms)

Plant fiber is resistant to alloenzymatic digestion (digestive enzymes secreted by the host/animals themselves)

Where the microbes live inside the animal’s GIT

Mechanical and alloenzymatic digestion before chemical and autoenzymatic digestion

A group of even-toed ungulate mammals that chew the cud regurgitated from its rumen. Have a compartmented stomach with 4 chambers: rumen, reticulum, omasum, abomasum.

Mechanical, chemical, and autoenzymatic digestion before alloenzymatic digestion

Where the microbes live inside the animal’s GIT

Mechanical and alloenzymatic digestion before chemical and autoenzymatic digestion

A group of even-toed ungulate mammals that chew the cud regurgitated from its rumen. Have a compartmented stomach with 4 chambers: rumen, reticulum, omasum, abomasum.

Mechanical, chemical, and autoenzymatic digestion before alloenzymatic digestion

Where the microbes live inside the animal’s GIT

Mechanical and alloenzymatic digestion before chemical and autoenzymatic digestion

A group of even-toed ungulate mammals that chew the cud regurgitated from its rumen. Have a compartmented stomach with 4 chambers: rumen, reticulum, omasum, abomasum.

Mechanical, chemical, and autoenzymatic digestion before alloenzymatic digestion

Where the microbes live inside the animal’s GIT

Mechanical and alloenzymatic digestion before chemical and autoenzymatic digestion

A group of even-toed ungulate mammals that chew the cud regurgitated from its rumen. Have a compartmented stomach with 4 chambers: rumen, reticulum, omasum, abomasum.

Mechanical, chemical, and autoenzymatic digestion before alloenzymatic digestion

Beak -> Head gut, acts as the mouth

Crop and Proventriculus -> Foregut, crop acts as storage, and Proventriculus secretes the HCl and the enzymes to break down the food and mush it up the "True Stomach"

Ventriculus (Gizzard) -> Midgut, mashes up the food that's been softened by the proventriculus

Crop, Proventriculus, and Ventriculus (Gizzard) ->Foregut, Crop acts as storage, the Proventriculus secretes the HCl and the enzymes break down the food the "True Stomach" , and the Ventriculus mashes up the food

They have two ceca

They share similar cecum structure with reptiles

There isn't anything unique

Abomasum -> Omasum -> Reticulum -> Rumen

Abomasum -> Rumen -> Reticulum -> Omasum

Rumen -> Reticulum -> Abomasum -> Omasum

Rumen -> Reticulum -> Omasum -> Abomasum

Increased utilization from low quality feedstuff (e.g., forage) due to microbial protein and vitamin synthesis

Can utilize non-protein nitrogen (e.g., urea)

Animals have prior access to the nutrients (e.g., easily digestible, high-quality protein and CHO)

Increased utilization from low quality feedstuff (e.g., forage) due to microbial protein and vitamin synthesis

Can utilize non-protein nitrogen (e.g., urea)

Animals have prior access to the nutrients (e.g., easily digestible, high-quality protein and CHO)

Some nutrients may be unavailable to the host due to microbial fermentation (e.g., glucose

Lower utilization/recovery of the fermentation products since it occurs after the major absorption site (some can be absorbed through LI but most can’t)

Therefore, coprophagy (eat their own poop)

Some nutrients may be unavailable to the host due to microbial fermentation (e.g., glucose

Lower utilization/recovery of the fermentation products since it occurs after the major absorption site (some can be absorbed through LI but most can’t)

Therefore, coprophagy (eat their own poop)

Foregut fermenters as the stomach holds some of the food

Hindgut fermenters as there is some (not a lot) fermentation capacity in the hindgut

Hindgut Fermenter

Foregut Fermenter

Midgut Fermenter

Hawk has EXTREMLY small ceca as it doesn't need to ferment the meat it eats

The Chicken has much larger ceca as it has a more grain and fiber diet

The Hoatzin has smaller ceca, larger than the hawk, due to it having a more carnivores diet, but also ferments some grains it eats

The Hoatzin has smaller ceca, larger than the hawk, due to it being a foregut fermenter rather than a hindgut fermenter

Rumen

Omasum

Abomasums

Reticulum

Sheep

Cow

Rabbits

Colobus Monkey

Sloth

Sheep

Cow

Rabbits

Colobus Monkey

Sloth

Llama

Camel

Rabbit

Colobus Monkey

Sloth

Llama

Camel

Rabbit

Koala

Rhinoceras

Llama

African Elephant

Rabbit

Koala

Rhinoceras

Very Simple

Short Large Intestine

Very complicated

Short Small Intestine

Long Large intestine

Long Small intestine

Short Large intestine

Short Small intestine

Long Large intestine

Long Small intestine

Short Large intestine

Short Small intestine

They eat a lot of low quality/nutritional food as with their GIT they are able to extract every last bit of nutrition from what they eat as the size of the GIT gives them ample time to do so

They eat a lot of high quality/nutritional food as they are able to get the surface level nutrients at first since they're able to break them down quickly in their stomach, but to get the rest of the nutrients they must ferment in the large intestine and are either absorbed there or consumed via feces

They eat a lot of low quality/nutritional food as with their GIT they are able to extract every last bit of nutrition from what they eat as the size of the GIT gives them ample time to do so

They eat a lot of high quality/nutritional food as they are able to get the surface level nutrients at first since they're able to break them down quickly in their stomach, but to get the rest of the nutrients they must ferment in the large intestine and are either absorbed there or consumed via feces

The cross-species study of adaptations and utilization of different nutrient sources.

We can use data of a well-researched animal with close relationship as a model.

The (unfounded) concept that animals have the innate ability to select from a novel compliment of foods to satisfy their nutrient requirements

The cross-species study of adaptations and utilization of different nutrient sources.

We can use data of a well-researched animal with close relationship as a model.

The (unfounded) concept that animals have the innate ability to select from a novel compliment of foods to satisfy their nutrient requirements

They share a very similar GIT structure with few differences. But their diets range from carnivores like that of the Polar bear to omnivores like the Sun Bear to the herbivorous Panda bear. With their GIT placed next to one another it's almost impossible to tell the difference, even though they have a wide range of diets

-

Plant Fibers

Microorganisms

Enzymes that are secreted by the host/animal themselves

Enzymes that are produced from the symbiotic microorganisms

Plant Fibers

Microorganisms

Enzymes that are secreted by the host/animal themselves

Enzymes that are produced from the symbiotic microorganisms

Plant Fibers

Microorganisms

Enzymes that are secreted by the host/animal themselves

Enzymes that are produced from the symbiotic microorganisms

Plant Fibers

Microorganisms

Enzymes that are secreted by the host/animal themselves

Enzymes that are produced from the symbiotic microorganisms

Bears

With the species that we have today we can see how vast their diets are and how even though they are closely related they have all adapted/evolved to either different or similar utilization of different nutrient sources

Fish

Given how they all are related on a very loose scale selecting a handful bunch is more than enough to show how they utilize different nutrient sources

Headgut, Mechanical Disruption -> Foregut, Mechanical disruption then Acid secretion -> Midgut, Absorption -> Hindgut, Fermentation

Headgut, Mechanical Disruption -> Foregut, Mechanical disruption then Acid secretion -> Midgut, Absorption -> Hindgut, Fermentation (A LOT OF IT)

Headgut, Nothing -> Foregut, Acid Secretion then Mechanical disruption -> Midgut, Absorption -> Hindgut, Fermentation (a lot of it)

Headgut, Mechanical Disruption -> Foregut, Fermentation (A lot of it) then a little Acid secretion -> Midgut Absorption (a lot) -> Hindgut, some fermentation

Headgut, Mechanical Disruption -> Foregut, Mechanical disruption then Acid secretion -> Midgut, Absorption -> Hindgut, Fermentation

Headgut, Mechanical Disruption -> Foregut, Mechanical disruption then Acid secretion -> Midgut, Absorption -> Hindgut, Fermentation (A LOT OF IT)

Headgut, Nothing -> Foregut, Acid Secretion then Mechanical disruption -> Midgut, Absorption -> Hindgut, Fermentation (a lot of it)

Headgut, Mechanical Disruption -> Foregut, Fermentation (A lot of it) then a little Acid secretion -> Midgut Absorption (a lot) -> Hindgut, some fermentation

Headgut, Mechanical Disruption -> Foregut, Mechanical disruption then Acid secretion -> Midgut, Absorption -> Hindgut, Fermentation

Headgut, Mechanical Disruption -> Foregut, Mechanical disruption then Acid secretion -> Midgut, Absorption -> Hindgut, Fermentation (A LOT OF IT)

Headgut, Nothing -> Foregut, Acid Secretion then Mechanical disruption -> Midgut, Absorption -> Hindgut, Fermentation (a lot of it)

Headgut, Mechanical Disruption -> Foregut, Fermentation (A lot of it) then a little Acid secretion -> Midgut Absorption (a lot) -> Hindgut, some fermentation

Headgut, Mechanical Disruption -> Foregut, Mechanical disruption then Acid secretion -> Midgut, Absorption -> Hindgut, Fermentation

Headgut, Mechanical Disruption -> Foregut, Mechanical disruption then Acid secretion -> Midgut, Absorption -> Hindgut, Fermentation (A LOT OF IT)

Headgut, Nothing -> Foregut, Acid Secretion then Mechanical disruption -> Midgut, Absorption -> Hindgut, Fermentation (a lot of it)

Headgut, Mechanical Disruption -> Foregut, Fermentation (A lot of it) then a little Acid secretion -> Midgut Absorption (a lot) -> Hindgut, some fermentation

Prehension (Grabbing)

Ingestion

Mastication (Chewing)

Deglutition (Swallowing)

Digestion (Mechanical and Enzymatic Only)

Digestion (Mechanical and Chemical Only)

Absorption

Metabolism

Prehension (Grabbing)

Ingestion

Mastication (Mechanical Digestion)

Mixing

Prehension (Grabbing)

Ingestion

Mastication (Mechanical Digestion)

Mixing

Prehension (Grabbing)

Ingestion

Mastication (Mechanical Digestion)

Mixing

Prehension (Grabbing)

Ingestion

Mastication (Mechanical Digestion)

Mixing

Prehension (Grabbing)

Ingestion

Mastication (Mechanical Digestion)

Mixing

Prehension (Grabbing)

Ingestion

Mastication (Mechanical Digestion)

Mixing

Prehension (Grabbing)

Ingestion

Mastication (Mechanical Digestion)

Mixing

Lubrication and enzymatic digestion

Split into Upper (maxillary) and lower (mandibular) arcades

Forms, numbers, and positions: highly variable among species

Indicative of diets (mammals mostly) Homodont vs. heterodont

Deciduous vs. permanent teeth (mammals)

Prehension, ingestion, and mastication

Prevent escape of live food

Crush prey items

All animals will equal amounts of the different kinds of teeth

Small teeth at the front

Nip, crop, gnaw

Long pointed teeth

Tear, puncture, and hold

Puncture and slice

Large flat teeth

Crush or grind

Small teeth at the front

Nip, crop, gnaw

Long pointed teeth

Tear, puncture, and hold

Puncture and slice

Large flat teeth

Crush or grind

Small teeth at the front

Nip, crop, gnaw

Long pointed teeth

Tear, puncture, and hold

Puncture and slice

Large flat teeth

Crush or grind

Small teeth at the front

Nip, crop, gnaw

Long pointed teeth

Tear, puncture, and hold

Puncture and slice

Large flat teeth

Crush or grind

Indicates number of each tooth type

Both upper and lower jaws

Usually just one side (Symmetric)

Only of the upper jaw as lower jaw will be the same regardless of species

2 [I U/L, C U/L, P U/L, M U/L]

1 [I U/L, C U/L, P U/L, M U/L]

2 [I L/U, C L/U, P L/U, M L/U]

2 [C U/L, I U/L, M U/L, P U/L]

2[I 3/3, C 1/1, P 4/4, M 2/3]

2[I 6/3, C 2/2, P 8/4, M 3/2]

2[I 3/3, C 1/1, P4/4, M 3/2]

All the same type of Teeth

All different kinds of Teeth

Early Stage Teeth (Baby Teeth)

Are forever teeth, no due over

All the same type of Teeth

All different kinds of Teeth

Early Stage Teeth (Baby Teeth)

Are forever teeth, no due over

All the same type of Teeth

All different kinds of Teeth

Early Stage Teeth (Baby Teeth)

Are forever teeth, no due over

All the same type of Teeth

All different kinds of Teeth

Early Stage Teeth (Baby Teeth)

Are forever teeth, no due over

All the same type of Teeth

All different kinds of Teeth

Early Stage Teeth (Baby Teeth)

Are forever teeth, no due over

The surface of the back teeth, mainly the ones that do the grinding

Last upper premolar [P3 (cats) or P4 (dogs)] and the first lower molar (M1) in most carnivorous mammals

Characteristic of mammals of the Carnivora order

Modified in such a way as to allow enlarged and often self-sharpening edges to pass by each other in a shearing manner • Cracking bones and shearing and cutting tendons

Modified in such a way as to allow enlarged and often self-sharpening edges to pass by each other in a shearing manner • Cracking bones and shearing Only

Last upper premolar [P3 (cats) or P4 (dogs)] and the first lower molar (M1) in most carnivorous mammals

Characteristic of Reptilia of the Carnivora order

Inscisors

Canines

Premolars

Molars

Carnassial

Inscisors

Canines

Premolars

Molars

Carnassial

Inscisors

Canines

Premolars

Molars

Carnassial

Inscisors

Canines

Premolars

Molars

Carnassial

Inscisors

Canines

Premolars

Molars

Carnassial

Variable in forms and functions

Have Papillae

Prehensile organ during digestion

Mixing food in mouth

Transport food posteriorly to esophagus

Sensory, Touch, temperature, taste (sweet, sour, bitter, salt, umami)

Prehensile organ during digestion Only

Serous Secretion

Salivary Amylase

Secrete Buffer

Mucins

Salivary Amylase

Carnivores only

Serous Secretion

Salivary Amylase

Secrete Buffer

Mucins

Salivary Amylase

Carnivores only

Serous Secretion

Salivary Amylase

Secrete Buffer

Mucins

Salivary Amylase

Carnivores only

Water

Mucin (Glycoprotein)

Bicarbonate Salts

Enzymes (Species specific)

Amylase
Lipase

Amylase is in ruminates, carnivores, birds, etc

Amylase is not in ruminates, carnivores, birds, etc

Water

Mucin (Glycoprotein)

Bicarbonate Salts

Enzymes (Species specific)

Amylase
Lipase

Amylase is in ruminates, carnivores, birds, etc

Amylase is not in ruminates, carnivores, birds, etc

Lubricant (Fibrous = dry and coarse)

Buffering Capacity (pH)

Nutrients (For the microbes)

Enzymatic capacity

Membrane protection

Protein Protection

Low Taste acuity

Salivary amylase and lipase present, but of minor importance

No upper incisors and canines Instead dental pad)

Continuous and large volume of saliva production (12 gal/d)

No Salivary amylase

Low Taste acuity

Salivary amylase and lipase present, but of minor importance

No upper incisors and canines Instead dental pad)

Continuous and large volume of saliva production (12 gal/d)

No Salivary amylase

Increase Surface Area

Help to tear grass as well as chew away at food by pressing it against their teeth and pad

They produce so much due to how they eat so much and really strip away to get every little nutrient they can get from their nutrient deficient food

They produce so much due to how they eat so much and really strip away to get every little nutrient they can get from their nutrient rich food

Increase Surface Area

Help to tear grass as well as chew away at food by pressing it against their teeth and pad

They produce so much due to how they eat so much and really strip away to get every little nutrient they can get from their nutrient deficient food

They produce so much due to how they eat so much and really strip away to get every little nutrient they can get from their nutrient rich food

Acts as a lubricant (fibrous = dry and coarse)

Buffering Capacity (pH)

Nutrients (For the microbes)

Enzymatic Capacity

Membrane Protection

Acts as a lubricant (fibrous = dry and coarse)

Buffering Capacity (pH)

Nutrients (For the microbes)

Enzymatic Capacity

Membrane Protection

Acts as a lubricant (fibrous = dry and coarse)

Buffering Capacity (pH)

Nutrients (For the microbes)

Enzymatic Capacity

Membrane Protection

Acts as a lubricant (fibrous = dry and coarse)

Buffering Capacity (pH)

Nutrients (For the microbes)

Enzymatic Capacity

Membrane Protection

Carbohydrates

Lipids

Proteins

Minerals

Yes, as for carnivores they have primarily protein based diets and thus having an enzyme that breaks down mainly carbs wouldn't support them much, same with most birds, and ruminants rely upon the microbes to produce and break them down on the chemical level, while the host focuses on breaking it down on the mechanical level

-

Stomach

Esophagus

Mouth

Small Intestine

Large Intestine

Tube or lumen space of variable dimensions

Control area outside the body

Lined by epithelia cells with different properties

Lined by non-glandular, non - keratinized stratified epithelium

Inner Body system

Out of Body system

From epiglottis to cardia

Lined by non-glandular, non - keratinized stratified epithelium

Transfer ingesta from the mouth to the stomach

Temporary site for food storage

Controlled regurgitation

Is combined with the trachea and has different ports by which food and air navigate

Moves material through the digestive tract

Alternating contractions and relaxations of circular muscle layers squeezing and longitudinal layers pushing

Prevent reflux of ingesta from esophagus back into the throat

Prevent gastric content from reentering into the esophagus

Moves material through the digestive tract

Alternating contractions and relaxations of circular muscle layers squeezing and longitudinal layers pushing

Prevent reflux of ingesta from esophagus back into the throat

Prevent gastric content from reentering into the esophagus

Moves material through the digestive tract

Alternating contractions and relaxations of circular muscle layers squeezing and longitudinal layers pushing

Prevent reflux of ingesta from esophagus back into the throat

Prevent gastric content from reentering into the esophagus

Storage, maceration, and trituration of food

Highly acidic: first line of defense

Gastric juice: water (97-99%), HCl (0.2-0.5%), digestive enzymes, hormones, salts, mucins, etc

Initial digestion • 20% of protein digestion, minimal fat and carbohydrate digestion • Secretes pepsinogen and HCl to initiate protein digestion

Prevent gastric content from reentering into the esophagus

Resulting stomach contents, ingesta mixed with HCl

-

Cardia (what lines the stomach)

Fundus

Body

Pylorus/Pyloric Sphincter

Cardia (what lines the stomach)

Fundus

Body

Pylorus/Pyloric Sphincter

Cardia (what lines the stomach)

Fundus

Body

Pylorus/Pyloric Sphincter

Cardia (what lines the stomach)

Fundus

Body

Pylorus/Pyloric Sphincter

Lipids

Carbohydrates

Protein

Minerals

Fundus

Corpus

Antrum

Pyloric Sphincter

Fundus

Corpus

Antrum

Pyloric Sphincter

Fundus

Corpus

Antrum

Pyloric Sphincter

Fundus

Corpus

Antrum

Pyloric Sphincter

Stomach Protection via mucus

Storage and Holding

Mechanical Mixing

Fermentation Site

Mucus, HCO3

Beginning of Stomach from the Esophagus

HCL and Pepsionogen

Mucus, HCO3

End of Stomach to Small Intestine

Stomach Protection via mucus

Storage and Holding

Mechanical Mixing

Fermentation Site

Mucus, HCO3

Beginning of Stomach from the Esophagus

HCL and Pepsionogen

Mucus, HCO3

End of Stomach to Small Intestine

Stomach Protection via mucus

Storage and Holding

Mechanical Mixing

Fermentation Site

Mucus, HCO3

Beginning of Stomach from the Esophagus

HCL and Pepsionogen

Mucus, HCO3

End of Stomach to Small Intestine

Stomach Protection via mucus

Storage and Holding

Mechanical Mixing

Fermentation Site

Mucus, HCO3

Beginning of Stomach from the Esophagus

HCL and Pepsionogen

Mucus, HCO3

End of Stomach to Small Intestine

Mucin

HCL

Pepsinogen

Rennin

Gastrin (Hormone)

Stratified squamous epithilieum

Cardiac gland region

Proper gastric region

Pyloric gland region

Stratified squamous epithilieum

Cardiac gland region

Proper gastric region

Pyloric gland region

Stratified squamous epithilieum

Cardiac gland region

Proper gastric region

Pyloric gland region

Stratified squamous epithilieum

Cardiac gland region

Proper gastric region

Pyloric gland region

Stratified squamous epithilieum

Cardiac gland region

Proper gastric region

Pyloric gland region/Pyloric Cells/G cell

Acts as protection for the sphincters incase there is a reflux from the stomach acid and it doesn't burn said linning

Is the main spot for where everything gets broken down and so it doesn't burn any protein wall lining outside the stomach

Is the main spot for where everything gets broken down and so it doesn't burn any protein wall lining outside the stomach

Is only seen in young mammals

What pushes out that food that's been broken down out of the stomach and into the small intestine

Acts as protection for the sphincters incase there is a reflux from the stomach acid and it doesn't burn said linning

Is the main spot for where everything gets broken down and so it doesn't burn any protein wall lining outside the stomach

Is the main spot for where everything gets broken down and so it doesn't burn any protein wall lining outside the stomach

Is only seen in young mammals

What pushes out that food that's been broken down out of the stomach and into the small intestine

Acts as protection for the sphincters incase there is a reflux from the stomach acid and it doesn't burn said linning

Is the main spot for where everything gets broken down and so it doesn't burn any protein wall lining outside the stomach

Is the main spot for where everything gets broken down and so it doesn't burn any protein wall lining outside the stomach

Is only seen in young mammals

What pushes out that food that's been broken down out of the stomach and into the small intestine

Acts as protection for the sphincters incase there is a reflux from the stomach acid and it doesn't burn said linning

Is the main spot for where everything gets broken down and so it doesn't burn any protein wall lining outside the stomach

Is the main spot for where everything gets broken down and so it doesn't burn any protein wall lining outside the stomach

Is only seen in young mammals

What pushes out that food that's been broken down out of the stomach and into the small intestine

Highly viscous organic secretion

Produced by cardiac and pyloric glands

Protects the mucosa from chemical and mechanical damage

Lubricant

Highly acidic (pH ~ 2)

Produced by gastric (fundic) parietal cells

Parietal cells also secrete the intrinsic factor

Denatures (unfolds) protein

Activates digestive enzymes

Pepsinogen ➔ pepsin

Kills Bacteria, 1st line of defense

Highly viscous organic secretion

Produced by cardiac and pyloric glands

Protects the mucosa from chemical and mechanical damage

Lubricant

Highly acidic (pH ~ 2)

Produced by gastric (fundic) parietal cells

Parietal cells also secrete the intrinsic factor

Denatures (unfolds) protein

Activates digestive enzymes

Pepsinogen ➔ pepsin

Kills Bacteria, 1st line of defense

Inactive proteolytic enzyme

Produced by gastric (fundic) chief cells

The active enzyme form: pepsin

Activated by HCl

Initiates protein digestion into polypeptides

Proteolytic enzyme produced by gastric (fundic) region cells

Only in young mammals

To coagulate milk to reduce the rate of passage

Hormone released from pyloric cells (G cell)

Due to stomach distension and/or presences of proteins

Stimulates HCl and pepsinogen secretion and gastric motility

The active enzyme form: pepsin

Activated by HCl

Initiates protein digestion into polypeptides

Proteolytic enzyme produced by gastric (fundic) region cells

Only in young mammals

To coagulate milk to reduce the rate of passage

Hormone released from pyloric cells (G cell)

Due to stomach distension and/or presences of proteins

Stimulates HCl and pepsinogen secretion and gastric motility

The active enzyme form: pepsin

Activated by HCl

Initiates protein digestion into polypeptides

Proteolytic enzyme produced by gastric (fundic) region cells

Only in young mammals

To coagulate milk to reduce the rate of passage

Hormone released from pyloric cells (G cell)

Due to stomach distension and/or presences of proteins

Simple Chamber

Can be pouched or diverticulated

Subdivided into 2 or more chambers

Can be diverticulated or haustrated

Mostly our foregut fermenters

Simple Chamber

Can be pouched or diverticulated

Subdivided into 2 or more chambers

Can be diverticulated or haustrated

Mostly our foregut fermenters

No glandular mucosa

Predominantly (If not all) glandular mucosa

Have a specific area, but still has them, varies by species

Ex. Monotremes, platypus/echidna

Ex. Humans and dogs

Ex. Horses and Pigs

No glandular mucosa

Predominantly (If not all) glandular mucosa

Have a specific area, but still has them, varies by species

Ex. Monotremes, platypus/echidna

Ex. Humans and dogs

Ex. Horses and Pigs

No glandular mucosa

Predominantly (If not all) glandular mucosa

Have a specific area, but still has them, varies by species

Ex. Monotremes, platypus/echidna

Ex. Humans and dogs

Ex. Horses and Pigs

Unilocular

Nonglandular

Rely on mechanical digestion in the stomach then enzymatic in SI

Due to dietary needs and or evolution

Plurilocular

Glandular

Unilocular

Composite

Some avian species (not all)

Many shapes

A thin-walled, expanded, muscular pouch of the esophagus

Mucous, no enzymes

Temporary food Storage

Moistening and Softening

"Crop Milk"

Fermentation - Hoatzin only

"True Stomach"

Produces mucous, HCl, and pepsin

Called the "True Stomach"

Smooth muscle

Cuticle/Koilin

Protective CHO/Protein membrane from HCl, digestive enzymes and grinding

For grinding and rushing

Produces mucous, HCl, and pepsin

Called the "True Stomach"

Smooth muscle

Cuticle/Koilin

Protective CHO/Protein membrane from HCl, digestive enzymes and grinding

For grinding and rushing

Tubular Gland

Gastric Gland

Tubular Gland

Gastric Gland

80% of a ruminant stomach by volume

Primary site of fiber digestion by anaerobic microbial fermentation

Wide, flat papillae

No Enzyme Secretion

Mucous secretion

Esophageal groove (young Only)

7-8% of a ruminant stomach by volume

Functions as the monogastric animal’s stomach

“True stomach”

Has glands and secretes enzymes

80% of a ruminant stomach by volume

Primary site of fiber digestion by anaerobic microbial fermentation

Wide, flat papillae

No Enzyme Secretion

Mucous secretion

Esophageal groove (young Only)

7-8% of a ruminant stomach by volume

Functions as the monogastric animal’s stomach

“True stomach”

Has glands and secretes enzymes

Aid in absorption by increasing surface area

Blind sacs

End products of fermentation: VFA and NH3

Help push food back to esophagus (regurgitation)

Help trap large food particles or foreign objects

“Hardware disease” (or bovine traumatic reticuloperitonitis)

To further reduce food particle size before moving to abomasum

Large surface area to absorb water, volatile fatty acid (VFA), and minerals (like sodium and potassium)

Aid in absorption by increasing surface area

Blind sacs

End products of fermentation: VFA and NH3

Help push food back to esophagus (regurgitation)

Help trap large food particles or foreign objects

“Hardware disease” (or bovine traumatic reticuloperitonitis)

To further reduce food particle size before moving to abomasum

Large surface area to absorb water, volatile fatty acid (VFA), and minerals (like sodium and potassium)

Aid in absorption by increasing surface area

Blind sacs

End products of fermentation: VFA and NH3

Help push food back to esophagus (regurgitation)

Help trap large food particles or foreign objects

“Hardware disease” (or bovine traumatic reticuloperitonitis)

To further reduce food particle size before moving to abomasum

Large surface area to absorb water, volatile fatty acid (VFA), and minerals (like sodium and potassium)

5% of a ruminant stomach by volume

Honeycomb-like lining

Contiguous with rumen

Reticulorumen

Ingesta movement

Rumination? ➔ Oral cavity

Mixing? ➔ Rumen

Passage? ➔ Omasum

7-8% of a ruminant stomach by volume

Leaf-like folds

Reticulo-omasal orifice (ROO)

5% of a ruminant stomach by volume

Honeycomb-like lining

Contiguous with rumen

Reticulorumen

Ingesta movement

Rumination? ➔ Oral cavity

Mixing? ➔ Rumen

Passage? ➔ Omasum

7-8% of a ruminant stomach by volume

Leaf-like folds

Reticulo-omasal orifice (ROO)

Normal rumen pH: 6.2-7.0

Clinical signs: anorexia, bloat, diarrhea, death if severe

Rumen pH drops significantly and rapidly (5.5-5.0) when consumes easily- and highly-fermentable feed • E.g., grains, high-sugar forages

Large amount of VFA

Shifts from fiber-digesting microbes to lactic acid-producing bacteria

Further lowing the pH

Normal rumen pH: 5.0-7.0

Clinical signs: anorexia, bloat, diarrhea, death if severe

Shifts from fiber-digesting microbes to lactic acid-producing bacteria

Further increaing the pH

Major Site of digestion and absorption

Digestion of carbohydrate, protein, and fat

Absorption of the end products of digestion, vitamins, and minerals

Secretions

Composed of the Duodenum, Jejunum, and Ileum

Absorption of water only

Secretions

(Mostly) Digestion

Digestion and Absorption

(Mostly) Absorption

(Mostly) Digestion

Digestion and Absorption

(Mostly) Absorption

(Mostly) Digestion

Digestion and Absorption

(Mostly) Absorption

Gastric Hormones

Succus Entericus ("Interstinal Juice")

Duodenal juice • Secreted by Brunner’s glands

Alkaline secretion (buffering) & Lubricant

Bile

Pancreatic Juice

Lipase

Amylase

Trypsinogen

Pepsinogen

Gastrin

Secretin

Cholecystokinin (CCK)

Gastric inhibitory peptide (GIP)

Mucousin

Hydrochloric Acid (HCl)

Tyrpsinogen

Pepsinogen

Originates in duodenum wall cells

Release in response to lipid and protein in duodenum (CCK)

Inhibits stomach acid

Stimulates pancreatic and bile secretions

Originates in duodenum wall cells

Release in response to lipid and protein in duodenum (GIT)

Inhibits stomach acid and enzymes

Decrease stomach motility

Originates in duodenum wall cells

Release in response to lipid and protein in duodenum (CCK)

Inhibits stomach acid

Stimulates pancreatic and bile secretions

Originates in duodenum wall cells

Release in response to lipid and protein in duodenum (GIT)

Inhibits stomach acid and enzymes

Decrease stomach motility

Originates in duodenum wall cells

Release in response to lipid and protein in duodenum

Inhibits stomach acid

Stimulates pancreatic and bile secretions

Originates in duodenum wall cells

Release in response to chyme and acid

Stimulates production of pancreatic juice for buffering

Stimulates decreased stomach motility and acid

(pH ~7-8)

Produced by the liver, stored in the gallbladder, enters into the duodenum via bile duct

98% of is recycled

Clear and watery liquid

(pH ~7-8)

Produced by the liver, stored in the gallbladder, enters into the duodenum via bile duct

98% of is recycled

Clear and watery liquid

Fat emulsification

Pancreatic lipase activation

(Does not contain digestive enzymes)

Produce Trypsinogen, chymotrypsinogen

Water

Cholesterol

Glycocholic and taurocholic bile salts

Bicarbonate ions HCO3 -

Bilirubin and biliverdin (breakdown product of RBC)

Chymotrypsinogen (to chymotrypsin)

Procarboxypeptidase (to carboxypeptidase)

Trypsinogen

Chymotrypsinogen,

Release bicarbonate ions to buffer chyme

Release digestive proenzymes and enzymes

Trypsinogen, chymotrypsinogen, procarboxypeptidase, amylase, lipase

Activates trypsinogen (to trypsin)

Chymotrypsinogen (to chymotrypsin)

Procarboxypeptidase (to carboxypeptidase)

Release bicarbonate ions to buffer chyme

Release digestive proenzymes and enzymes

Trypsinogen, chymotrypsinogen, procarboxypeptidase, amylase, lipase

Activates trypsinogen (to trypsin)

Chymotrypsinogen (to chymotrypsin)

Procarboxypeptidase (to carboxypeptidase)

Release bicarbonate ions to buffer chyme

Release digestive proenzymes and enzymes

Trypsinogen, chymotrypsinogen, procarboxypeptidase, amylase, lipase

Activates trypsinogen (to trypsin)

Chymotrypsinogen (to chymotrypsin)

Procarboxypeptidase (to carboxypeptidase)

Release bicarbonate ions to buffer chyme

Release digestive proenzymes and enzymes

Trypsinogen, chymotrypsinogen, procarboxypeptidase, amylase, lipase

Activates trypsinogen (to trypsin)

Chymotrypsinogen (to chymotrypsin)

Procarboxypeptidase (to carboxypeptidase)

Alpha Cells

Beta Cells

G Cells

Gamma Cells

Glucagon

Insulin

Increase Blood Sugar

Decrease Blood Sugar

Glucagon

Insulin

Increase Blood Sugar

Decrease Blood Sugar

Breakdown of complex food substances into constituent parts for use by the animal in maintenance processes and production

Complete digestion and absorption of food requires a lot of time

Autoenzymatic digestion

Alloenzymatic digestion

Attoenzymatic Digestion

Breakdown of complex food substances into constituent parts for use by the animal in maintenance processes and production

Complete digestion and absorption of food requires a lot of time

Autoenzymatic digestion

Alloenzymatic digestion

Attoenzymatic Digestion

Breakdown of complex food substances into constituent parts for use by the animal in maintenance processes and production

Complete digestion and absorption of food requires a lot of time

Autoenzymatic digestion

Alloenzymatic digestion

Attoenzymatic Digestion

Maximizing efficiency of digestion

Maximizing rate of digestion

Minimizing efficiency of digestion

Minimizing rate of digestion

Inactive: Pepsinogen

Active: Pepsin

Inactive: Trypsinogen

Active: Trypsin

Chymotrypsin

Elastase

Inactive: Pepsinogen

Active: Pepsin

Inactive: Trypsinogen

Active: Trypsin

Chymotrypsin

Elastase

Salivary Amylase

Pancreatic Amylase

Lingual Lipase

Pancreatic Lipase

Colipase

Bile salts and micelles

Salivary Amylase

Pancreatic Amylase

Lingual Lipase (minimal)

Pancreatic Lipase

Colipase

Bile salts and micelles (not enzymes but do the work)

Salivary Amylase

Pancreatic Amylase

Lingual Lipase (minimal)

Pancreatic Lipase

Colipase

Bile salts and micelles

Carbohydrates (Glucose, mono/disaccharides)

Protein (Amino acids, peptides)

Vitamins

Electrolytes and Water

Ions and Calsium

Bile acids and Vitamin B12

Carbohydrates (Glucose, mono/disaccharides)

Protein (Amino acids, peptides)

Vitamins

Electrolytes and Water

Ions and Calsium

Bile acids and Vitamin B12

All nutrients, except lipids (and lipid -soluble nutrients), are carried through the intestinal venous capillary system • ➔ portal vein ➔ Liver

Lipids are absorbed via the lacteal and transported through the lymphatic system

Less variable in form and function

High variability in form and function

Relatively Long

Relatively Short

More proteinases and less carbohydrases in carnivores than omnivores or herbivores

Less variable in form and function

High variability in form and function

Relatively Long

Relatively Short

More proteinases and less carbohydrases in carnivores than omnivores or herbivores

Less variable in form and function

High variability in form and function

Relatively Long

Relatively Short

More proteinases and less carbohydrases in carnivores than omnivores or herbivores

Less variable in form and function

High variability in form and function

Less proteinases and more carbohydrases in carnivores than omnivores or herbivores

More proteinases and less carbohydrases in carnivores than omnivores or herbivores

Emulsification, breaks down the lip droplets via bile salts attaching themselves onto them to widdle away at them

Digestion of lipase, then breaks them into free fatty acids that are then attached by more bile salt

Micelles then trap them inside for easier transport and absorption

Digestion of lipase, then breaks them into free fatty acids that are then attached by HCl

Are then transported via the Chylomicrons which transport said fat to where it needs to be

Plicae circulares (Mucosal folds)

Villi (mucosal projections)

Microvilli (Microscopic projections of apical surface of epithelial cells)

Villi (Microscopic projections of apical surface of epithelial cells)

Located between each villus

Site of first line of defense

Site of intestinal epithelial cell formation and differentiation

i.e., villi regeneration

Site of intestinal epithelial cell formation and differentiation

i.e., Microvilli regeneration

Located between each villus

Site of second line of defense

Duodenum

Jejunum

Ileum

Duodenum

Jejunum

Ileum

Duodenum

Jejunum

Ileum

Liver

Duodenum

Gallbladder

Pancreas

Liver

Duodenum

Gallbladder

Pancreas

Liver

Duodenum

Gallbladder

Pancreas

Liver

Duodenum

Gallbladder

Pancreas

Gallbladder

Liver

They cluster as due to the space of the body they are unable to spread across the small intestine

They cluster as they all secrete their enzymes, bile, and whatever else into the Duodenum so they can really get broken down, and absorbed by the Jejunum and Ileum

Gallbladder

Liver

They cluster as due to the space of the body they are unable to spread across the small intestine

They cluster as they all secrete their enzymes, bile, and whatever else into the Duodenum so they can really get broken down, and absorbed by the Jejunum and Ileum

Cecum/Ceca

Colon (Subdivisions)

Rectum

Jejunum

Ileum

Absorption of water, electrolytes, and some minerals

Microbial fermentation

Storage and excretion of wastes

Absorption of protein, starches, and lipids

Autoenzymatic digestion

Alloenzymatic Digestion

Attoenzymatic Digestion

Relatively short and simple

Cecal Fermenters

Colon Fermenters (Different sections of colon)

Ceca and Cloaca

Relatively short and simple

Cecal Fermenters

Colon Fermenters (Different sections of colon)

Ceca and Cloaca

Relatively short and simple

Cecal Fermenters

Colon Fermenters (Different sections of colon)

Ceca and Cloaca

This is due to them being enzymes that breakdown protein and if they were always active they'd breakdown the lining of the stomach walls

-

Very important strategy for fiber degradation/digestion

Animals do not have the enzymes to breakdown fiber, but the microbes can (alloenzymatic digestion)

A symbiotic relationship

A mutualistic relationship

Animals do not have the enzymes to breakdown fiber, but the microbes can (autoenzymatic digestion)

Environment (temperature and pH)

Nutrients (water, ingesta/ digesta)

Anaerobic environment

Supply of nitrogen

Mixing

Removal of end products and fermented digesta

Anaerobic environment

Supply of Hydrogen

Enzymes to breakdown fiber

Volatile fatty acid (VFA) or short - chain fatty acid (SCFA) production

Protein synthesis

Convert N into ammonia and microbial protein

B vitamins and vitamin K synthesis

Detoxify secondary plant metabolites

C vitamins and vitamin B synthesis

Detoxify secondary plant metabolites

Protein synthesis

Convert H into ammonia and microbial protein

Acetate

Propionate

Butyrate

Flucitate

Carbonate

Microbes are only found within the specific part of the GIT they are needed in and are all the same

Microbes are found all along the GIT just a various numbers, and each have their different niches

It's when an animal consumes a whole prey

It's when an animal eats primarily parts of the prey whole

Collagen in skin, tendons, ligaments

Keratin in hair and fur

Chitin in insects

Blood and meat

It is when an animal has an imbalance of microbes in their GIT

It is when an animal has a balance of microbes in their GIT

It when they take health feces with well populated microbes and feed it to an unhealthy animal

It when they take health urine with well populated microbes and feed it to an unhealthy animal

It is when an animal has an imbalance of microbes in their GIT

It is when an animal has a balance of microbes in their GIT

It when they take health feces with well populated microbes and feed it to an unhealthy animal

It when they take health urine with well populated microbes and feed it to an unhealthy animal

Buccal

Gastric

Pancreatic

Hepatic (Liver)

Intestinal

Kidney

Intestinal