Animal Science Exam #2 Study guide

The Endocrine System is made up of...

1.Hypothalamus 2.Pituitary 3.Thyroid & Parathyroid Glands 4.Adrenal Glands 5.Ovaries (Female) & Testes (Male) 6.Pancreas

Experience stimuli

Animals learn from interactions they have had with their environment. -avoiding things that previously resulted in a bad experience. -For example some butterflies are toxic to animals that eat them. These butterflies usually have bright and elaborate wing patters so that predators can easily recognize them as toxic and thus avoid them.

Thoughts related to internal stimuli

Animals preferences and motivations. -They never do things for no reason at all. Their behavior always indicates some underlying mechanism at work.

Social behaviors associated with feeding

Feeding competition, Hunting, and communication and learning

What animal has the largest cecum that we know of?

Capybara

In horses, the majority of microbes that are needed to break down cellulose are located in the _______.

Cecum

Types of internal stimuli?

Hormones, physiological state, and thoughts

What chemical in the stomach activates enzymes?

Hydrochloric Acid (HCL)

What enzymes do the stomach contain?

Lipase and Protease (Pepsin)

monogastrics (nonruminants)

Simple Stomach; one gastric. Mono-gastric animals (most omnivores and all carnivores) don't need a complicated stomach since they eat food that is easy to digest.

Ruminants have no top teeth.

True

Ruminants need lots of bacteria in their stomach to break down cellulose.

True

Ruminants will spend about 8 hours per day ruminating.

True

The length of the digestive tract correlates to how easy the food is to digest.

True

The pancreas is also critical for recognizing when there is an abundance of nutrients in the blood.

True

Abomasum

True stomach of ruminants

Animals that eat more plant matter have a larger cecum.

True

HCL and bile salts are not an enzyme

True

Hippos are non-ruminant

True

Enzymes from the Small intestine Brush Border

lactase, maltase, peptidase. -These enzymes finish the job, reducing the macromolecules into their smallest subunits (monosaccharides and amino acids)

sections of small intestine

duodenum, jejunum, ileum

continuous feeders

grazing animals; eat lower quality food, food is scattered

Gluconeogenesis

formation of glucose

Epimeletic behavior

giving care and attention

Trypsinogen

inactive form of trypsin; -Trypsinogen converts to Trypsin when it interacts with the acidic chyme that has just entered the small intestine from the stomach.

components of digestive system

mouth, esophagus, stomach, cecum, small and large intestines and rectum

Simple Behavior

muscle contractions in response to some stimulus like a tap to your knee, reflex actions, instinct.

The microbes help the ruminant by:

-Digesting of cellulose and hemicellulose (structural carbohydrates) that cannot be broken down by enzymes -Providing high quality protein (in the form of deceased microbes) -Producing Volatile fatty Acids - the major energy source for the ruminant -Providing B vitamins-Detoxifying toxic compounds

large intestine

-Absorbs water and forms feces -The major site of microbial (e.g bacteria) fermentation (breakdown of hard to digest plant material, aka cellulose).

The ruminant helps the microbes by:

-Providing microbes with an optimal place to live and grow (i.e. the rumen) -Feeding them -Removing the waste of the microbes (which is actually the VFA's ruminants need to survive!)

Hormones related to internal stimuli

-Testosterone is a male sex hormone and it is responsible for many of the dominate/aggressive type behaviors seen in males particularly around the time of mating -Ghrelin which is a hormone produced in your stomach when your stomach is empty. It sends a message to the brain tell you that you're hungry and that you should eat.

unsacculated colonic digesters

-do not have a need for the sacculated intestine because they have very limited ability to digest fiber. -Take note of the "smoothness" of the large intestine. -cats, dogs (and other carnivores)

Examples of pre-gastric fermenters

-ruminants (cow, goat, sheep, camel, deer, antelope) -non-ruminants (kangaroo, hippo, colobus monkey, hamster, vole)

Hormones related to nutrition include

1. Ghrelin 2. Leptin 3. Secretin 4. CCK (Cholecystokinin) 5. Insulin 6. Glucagon

Steps of rumination are

1. Regurgitation -Moving food from the stomach back up into the mouth. 2. Remastication - Chewing the food for the second time. 3. Rein salivation - Mixing the with additional saliva 4. Re-swallowing - Swallowing the food for the second time.

Ghrelin

A hunger-arousing hormone secreted by an empty stomach

Rectum

A short tube at the end of the large intestine where waste material is compressed into a solid form before being eliminated

What enzymes do the mouth contain?

Amylase and Lipase

What enzymes do the small intestine contain?

Amylase, Lipase, and Protease

Why do herbivores have longer digestive tracts?

Carnivores eat meat; protein is quite easy to digest and absorb. Omnivores and herbivores eat more plants which take longer to digest. A longer small intestine gives more time for enzymes to break down the plant food as it slowly moves along the digestive tract. This optimizes the amount of nutrients that can be extracted from plants!

Five Categories of Animal Behavior

Communication Social behaviors Feeding behaviors Reproductive behaviors Maternal/Neonatal behaviors

Communication and learning

Communication & Learning; animals learn particularly when they are young, where to find food, how to eat, and what types of foods are safe to eat!

Ruminants

Complex stomach; Four stomachs The function of the four compartments is to break down the hard-to-digest grasses with cellulose. -The last part of a ruminant stomach (the abomasum or real stomach) functions exactly like the monogastric stomach

Complex behavior

Complex: bird migration, mating rituals, hibernation, reproduction, grooming, feeding, locomotion, etc.

Amylase enzymes

Digest carbohydrates into simple sugars.

Lipase Enzymes

Digest lipids into fatty acids

Protease Enzymes

Digest proteins into amino acids

Reticulum

Digesta flows freely between the rumen and reticulum. There is no enzymatic activity here. -Contracts to help regurgitate food for rumination. -Characterized by honeycomb" lining.

small intestine

Digestive organ where most chemical digestion and absorption of food takes place. -important accessory organs to break down all three macromolecules: The Liver and Pancreas.

hindgut fermenters

Do all of their fermentation in the cecum and large intestine.

pre-gastric fermenters

Do most of their fermentation of food BEFORE the "true" stomach (e.g. abomasum in ruminants). The "true" stomach has the acid and enzymes for digestion.

Types of external stimuli?

Environment and experience

villi

Fingerlike extensions of the intestinal mucosa that increase the surface area for absorption in the small intestine.

duodenum

First part of the small intestine. -Most digestion takes place in this section. All types of macromolecules are digested here via enzymes (carbohydrates, protein and fat)

peristalsis

Involuntary waves of muscle contraction that keep food moving along in one direction through the digestive system.

relationship between leptin and ghrelin

Leptin is a mediator of long term regulation of energy balance, suppressing food intake and thereby inducing weight loss. Satiety Ghrelin, on the other hand, is a fast acting hormone, playing a role in meal initiation. Hunger

physiological state related to internal stimuli

Occurs when animals are pregnant, ready to mate, etc. -For example, when a cow is ready to delivery her calf she becomes a lot more restless approximately 11 hours prior to birth.

Enzymes from the Pancreas

Pancreatic amylase, trypsin, pancreatic lipase. -These enzymes start breaking down the big macromolecules

Two important cells of the stomach wall

Parietal and Chief

Maternal behaviors examples

Placentophagia, nest building, and maternal agression

Mastication

Process of chewing

six basic nutrients post-digestion

Proteins-Amino Acid Lipid-Fatty Acid Carbohydrates-Monosaccharide vitamins minerals Water

cecal fermenters

Size of the cecum compared to the large intestine is much larger (holds more food) -rabbits and rats

Environment stimuli

Something in the animal's environment causes or influences the behavior. -The horse is a herd animal and its' instinct it to flee when it perceives a threat. -a stimulus in their environment is new or perhaps moves or makes noise (i.e. trees blowing in the wind), causing a horse to become startled or run

Feeding behavior examples

Sorting Behavior and Exploratory/ investigative Behavior

Fermentation

The chemical breakdown of a substance (e.g. forages like grass) by bacteria, yeast or other micro-organisms. Microbes are specialized to digest foods high in cellulose (aka Fiber).

Sacculated colonic digesters

The design of the colon is sacculated (meaning lots of folds or pockets) to provide more surface area for microbes to ferment cellulose. -Horses, humans, and pigs

Goal of digestion

The goal of digestion is to reduce complex macromolecules into simple subunits.

Examples of harvesting equipment

The mouth, prehensile, mastication, and teeth.

Hunting

This is an example of cooperation to get food.

Lordosis (swayback)

This reflex behavior, is a naturally occurring body posture for sexual receptivity to copulation present in most mammals including rodents, elephants, and cats. The back arches so that the pelvis of the female is at an optimal angle for copulation with the male.

Communication examples

Visual; an example is cats (and most other animals) communicating through establishing specific body positions when threatened or frightened. Auditory; Most social species have elaborate systems of vocalizations that humans are just beginning to understand. Olfactory; Animals use scent (e.g. urine or other body fluids) to mark territories and help with the recognition of their peers/family. Touch; Just like humans some animals use touch to communicate complex emotions or feelings. Many species of apes for example use touch as a form of consolation to make the other feel better. Other forms of touch seem to occur only to antagonize the receiver! Electro; Animals that either generate or receive electric fields are found only in wet or aquatic environments due to water's relatively low electrical resistance, compared to other substances. Electric eels use this. Seismic; Information is conveyed through mechanical vibrations of the substrate (e.g. dirt, sand, web, honeycomb, etc.). The star-nosed mole (Links to an external site.) (Condylura cristata), has evolved an elaborate nose structure which may detect seismic waves. Spiders can communicate location of prey and test for faults in their web by using tiny vibrations.

Sodium Bicarbonate (NaHCO3)

a buffer from Duct Cells which quickly neutralizes acid from the stomach.

pharynx

a common passage for food and air, lined by a mucous membrane and surrounded by muscle.

cecum

a pouch connected to the junction of the small and large intestines. -major site of microbial and cellulose fermentation

Discontinuous feeders

active, highly mobile animals; more specialized digestion; take in large meals

Animal Behavior

an action, activity, or process which can be observed and measured.

How do enzymes work?

binding to a macromolecule and then breaking the bond that holds the macromolecule subunits together

prehensile

capable of grasping

et-epimeletic behavior

care seeking

Feeding competition

commonly observed in animals since food is such an important resource at its availability may be limited for a number of reasons (e.g. growing season, temperature, space availability for feeding. Competition can be expressed in terms of threats (growls, baring teeth, aggressive body posture) and physical attacks.

Sexual/reproductive behavior examples

courtship, signaling of receptivity (estrus/"heat", and swayback) and process of copulation.

function of bile

emulsify fats

Leptin

hormone that signals the hypothalamus and brain stem to reduce appetite and increase the amount of energy used

Examples of hindgut fermenters

horses and rabbits

Placentophagia

ingestion of the placenta to create a bond with an animals offspring. Scents and pheromones that come from the placenta help the mother recognize the offspring as her own.

What are the types of salivary glands?

parotid, submandibular, sublingual

neonatal

pertaining to newborn

liver

produces bile

rBST & rGH

recombinant Somatotropin and recombinant Growth Hormone

Jejunum

second part of the small intestine. -Major site of nutrient absorption of nutrients. Water absorption also occurs here.

parietal cells

secrete HCl

chief cells

secrete pepsinogen

Rumen

stomach chamber in cows and related animals in which symbiotic bacteria digest cellulose. -characterized by the carpet like lining with many projections

gall blader

stores bile

colonic digestors

the cecum is much smaller relative to the large intestine

Maternal behavior

the formation of a bond between mother and offspring. Involves hormonal regulation. Neonatal behavior can reflect learning in young and provide insights into development.

Ileum

the last and longest portion of the small intestine. -Continuation of absorption of nutrients and water. -Connects to the large intestine and cecum

standing heat (estrus)

the short window of time that a female is sexually receptive meaning she has just ovulated an egg which is ready to be fertilized by sperm.

Omasum

water absorption