Animal Science Test 2

What are behaviors (Feeding, sexual cycles, and physiological responses) Influenced by?

Light/dark cycles, temperature changes, hormones, and barometric pressure.

Both sexual and maternal behaviors are

influenced by a range of development and genetic factors, and both endocrine and nervous systems.

Sexual behavior

Study of social and sexual experiences where the environment promotes normal mating behaviors and correct abnormal behaviors.

Maternal behaviors

Study all aspects of mother and offspring to include bonding between mother and offspring, recognition, negligence from mother, nursing, etc.

Sow example

Sows(female pigs who have given birth) are needed by large production industries to produce large litters and to either be lactating/gestating with little nonproductive time.

Farrowing pens allow the sow freedom to move about and prevent crushing the piglets.

Development behavior

animals respond favorably to certain types of training at developmentally favorable times.

Do all animals exhibit aggressive behaviors?

Yes, all animals have aggressive behaviors.

When do aggressive behaviors in animals typically increase?

Aggressive behaviors typically increase during mating seasons, maternal protection, and protection from predators.

What problems can arise from aggression in animals?

Problems with aggression arise when people and animals compete for dominance.

How do animals receive communication?

Visual, auditory, and olfactory means.

Classical conditioning

use of sound, light, or touch to train a specific response.

Habitual learning

Ability for an animal to ignore something that occurs often.

Operant/Instrumental Conditioning

Learning influenced by its effects.

Imprint learning

Ability for young animals to find their mother and their own kind.

How are restraints used on animals?

They can be taught to be voluntarily accepted by gentle animals. They are used in artificial insemination, inoculation, hoof cleaning and vet checks.

Temperament

Characteristic behavior/mode of response. Influenced by genetics and environmental factors. Dictates reactions during animal handling.

What can influence the use of restraints?

Temperament

Herd/flock instincts

All livestock live in a herd(group). Individuals may become highly stressed when separated.

Fear:

previous experience with handling affects reaction to future handling.

What influences herd/flock instincts?

Fear

Ingestive behavior

involves factors controlling feed intake such as palatability, herd behaviors, environment and hormones, Meal patterns, quantity, and timing.

Example of ingestive behavior

Use of genetics to couple positive learning and ingestive behavior together. Ingestive behavior is focused on calves eating and gaining weight(Hereford>Angus>Brahman). Learning focuses on excitability levels(Brahman>Angus>Hereford).

Why does animal health need to be maintained?

Disease prevention is more cost effective.

Healthy animals are more likely to produce more.

Where do stressors come from?

Natural and artificial environments.

Artificial environment

Factors linked to the economic level and culture+controls over natural environment.

natural environment

Climate, Geography, altitude, feed

The 5 major environmental stressors

Climate, Nutritional, Internal, Geographical, Social

Climate (stressor)

long-term pattern of weather factors such as temperature, precipitation, solar radiation, wind, and humidity.

Nutritional (Stressors)

Quantity/quality of available feedstuff determined by climate.

Internal(Stressors)

Affects individuals by gaining entrance to the body (pathogens, viruses, toxins).

Geographical (Stressors)

Nonclimatic stresses associated with a particular geographic.

Social (Stressors)

Interactions with other animals including those within the same species and humans.

Disease

Any state other than complete health.

Signs of disease.

Fever, weight loss, edema, reduced performance, and lesions(change in size, color, and shape of an organ.)

Acute Diseases

Sudden onset of clinical signs and a short duration of illness.

Chronic Diseases

Symptoms developing slowly over weeks/months with early symptoms being easily overlooked and nonspecific.

Predisposed causes of diseases

Stress factors that make the animals more susceptible to the disease.

Direct causes of diseases

Infectious etiologies include bacteria and viruses, Protozoa and parasites, fungi and prions.

Infectious Diseases

Caused by living organisms (pathogens).

Requirements of infection/perpetuation

Gain entrance into body.

Pathogen adapts and multiplies.

Exit host.

Infect another host to make the pathogen contagious.

Noninfectious disease

Caused by nutrient deficiencies, genetic makeup, hazards resulting in traumatic injury, and metabolic disturbances(poisons).

Agricultural animals must be able to adapt to the natural and artificial environment imposed by humans and associated stressors.

True

Innate Immunity

First line of defense against infection, certain white blood cells and other immunity proteins and chemicals attack pathogens.

Examples of innate immunity

Macrophages engulf pathogens and debris.

Complement proteins aggregate and punching holes in bacteria so the cells open.

Con of innate immunity

Does not provide specific, long-lasting protection against pathogens.

Mechanisms of innate immunity

Surface barriers (Skin, Mucous membranes) and Protective reflexes (Coughing, sneezing, and tearing).

Adaptive immunity

Specific and long-term defense against new and previously encountered pathogens. Dependent upon body's ability to produce antibodies

Pro of adaptive immunity

Guides white blood cells to destroy specific targets.

Con of adaptive immunity

Can result in the body targeting its own cells.

Antibodies

Proteins produced by antibody-secreting plasma cells. Present in body fluids. Passed in maternal passive immunity and active immunity.

Active immunity

Antibodies made by the animal's own immune system (thru vaccination or exposure to a pathogen).

Maternal Passive immunity

Collection of antibodies against infections the mother has been exposed to. Transferred to offspring thru placenta or milk. Lasts 3-4 weeks.

Herd health management

Applies to all horses and livestock, Necessary for both large and small scale production.

Program Guidelines of Herd Health management

1. Management

2. Nutrition

3. Genetics

4. Preventative care

How is genetics involved in herd health management?

elimination of genetic faults in animals thru pedigree analyses, test mating, and laboratory profiling of DNA.

What is meant by preventative care in herd health maagement?

Vaccination, proper housing, veterinary services, appropriate handling equipment.

Identify Health and Safety risks for workers.

Worker's health is at risk from extreme heat and extreme cold.

Personal Protective Equipment(PPE)

Air contaminants: Dust, Pesticides, poison gas

Proper storage of chemicals for prevention.

Why do we use squeeze chutes, headgates, pens, and restraints?

help direct animals for procedures such as vaccination, grooming, collection/distribution of body fluids.

What vision do livestock have?

Wide angle: Visual field of 300 degrees

Flight Zone

Area where an animal would move away from an intruder if spotted.

Curved chute

Single file movement. Prevents animal from seeing what is at the end until it gets there. Encourages natural tendency to circle around handlers

Squeeze chutes

Eliminates visual distractions, reduces external noises, includes anti-back-up gates.

Genetic

the study of heredity,or the way in which traits of parents are passed on to offspring.

How does genotype set the stage for pheotype?

disposition, coat type, coat color, speed, gait types, body composition• growth, reproduction, milk production, disease resistance, and other traits.

How does the expression of genotype into traits of economic importance provide the basis for an animal's worth when marketed?

Livestock producer standpoint - efficiency of production

Consumer's position - tenderness, flavor, color, and leanness might top the list of important characteristics.

applied genetics

Referred to as animal breeding. Advances made possible thru genetic engineering.

Population genetics

studies gene frequency and heritability due to environmental and other influences

Additive effect of genes:

Many different genes are involved in the expression of a trait. Results in quantitative traits.

Example of additive effect of genes

Carcass traits, weight gain, and milk production are traits that have moderate to high heritability

Nonaditive effect of genes.

Control traits by determining how gene pairs act in different combinations with one another. Involves traits that are observable, controlled by one or more genes. Results in qualitative traits.

Example of Nonadditive effect of genes

influence of agouti gene on black or red coloring for a horse.

Structure of DNA

Nucleotides are made of a deoxyribose sugar, a nitrogenous base, and a phosphate group

Double Stranded structure, nucleotide pairs(AT/CG) are held with hydrogen bonds.

Stacks of nucleotide pairs are held by phosphodiester bonds.

Role of DNA

serves as a template and has segments that code for the manufacture of RNA

Transcription

The process of using DNA to code for RNA. Occurs in the nucleus.

RNA

instrucions to make proteins called messenger RNA(mRNA)

mRNA

template for manufacturing proteins

Translation

The process of using mRNA to manufacture proteins. Occurs at the ribosomes. Requires transfer RNA (tRNA) to bring amino acids to the ribosomes.

Alleles

Various protein forms of a gene. Results from random mutations and exchanges of material in cell division.

Meiosis

Cell division that increases the number of gametes (sperm/egg). Ensures the presence of genetic differences. Creates 4 genetically different haploid cells.

Mitosis

Cell division used by somatic cells. Does not result in genetic differences. Produces 2 identical diploid cells.

Gametes

Sperm and egg cells are haploid , containing half the genetic code of each parent. This ensures equal contribution when fusing to create a zygote.

Dominant gene

one member of a gene pair is expressed to the exclusion of the other.

Recessive gene

only expressed when the dominant allele is absent from the animal's genome

Homozygous

carry two of the same allele for the gene

Heterozygous

carry two different alleles for the gene

Co-dominance

Both genes are expressed in the phenotype

*Must be heterozygous

Incomplete dominance

No dominance exists; a heterozygous individual has an intermediate phenotype

Epistasis

Cases where many gene pairs act in concert to produce a given phenotype where the expression of 1 gene is influenced by the presence of another gene

Multiple alleles

Genes that have 3 or more differentalleles within the gene pool

Ex: Blood type

Sex-linked inheritance

Inheritance of genes found only oneither the X or Y chromosome formammals, Z or W chromosomesfor birds

*Commonly inherited from the X chromosome

Sex-influenced inheritance

Genes inherited on autosomes (all other chromosomes) and the expression of the gene is dependent upon whether the individual is genetically male or female

Sex-limited traits

Both sexes carry the genes, but only 1 sex is capable of the expression.

Phenotypic expression of some genes is determined by the presence or absence of one of the sex hormones

Artificial Selection

based on management decisions to allow certain animals more opportunity to mate and produce offspring than others

Qualitative traits

Phenotypes that are classified rather than numerically measured.

Ex: The presence or absence of horns on sheep or cows.

Quantitative Traits

numerically measured and usually controlled by many genes.

Ex: number of eggs produced by poultry, gallons of milk produced by cows.

Carcass merit traits

Highly heritable with a range of 40-60%

Growth traits

Moderately heritable with a range of 20-40%

Reproductive ability

Traits with a low heritability range such as 0-20%

Calculating heritability problems

1. calculating selectional differential: Desired average-current average.

2. Multiply the heritability factor by the selectional differential.

3. Add the product to the current average for the gain in litter size.

Sexual reproduction in animals

Occurs in the gonads. Includes:

1. Copulation

2. Fertilization

3. Embryo

4. Parturition