Definitions

Colostrum

first milk secreted after calving

scours

loose manure that lasts for two or more days and can be accompanied by a decrease in appetite lethargy dehydration and fever

Weaning

act of taking a young animal off milk as the main source of nutrition

Acute mastitis

Mastitis characterized by sudden onset, redness, swelling, hardness, pain, grossly abnormal milk, and reduced milk yielda

agitator

stirs milk in the bulk tank to help with cooling and to provide a uniform product mixture for sampling

alveoli

spherical clusters of secretory cells in the mammary gland that are arranged in grape like structures

bulk tank

a large storage tank for cooling and storing milk at a cold temperature until it is transported to a processing plant; usually made of stainless steel

chronic mastitis

mastitis that continues over a long period of time, with progressive development of scar tissue and simultaneous reduction in milk yield

clinical mastitis

mastitis characterized by visible abnormalities in the udder or milk

foremilk

first streams of milk stripped from the udder prior to milkiing

forestripping

process by which the first few streams of milk are removed from the teat prior to milking to observe for abnormalities and to flush the teat canal

inflammation

Condition in which the cow's body seeks to eliminate or neutralize invading microorganisms and repair damaged tissue 

Keratin

Waxy substance produced by cells lining the teat canal that serves as a plug between milkings and aids in reducing penetration by microorganisms 

lactation

period when the cow is in milk

mastitis

an inflammation of the udder, most caused by infecting microorganisms

milk letdown

process through which milk is squeezed out of milk-producing tissue by the action of the hormone oxytocin

milk line

line that carries milk and air during milking and has the dual function of providing milking vacuum and conveying the milk to the receiver

pulsation

the cyclic opening and closing of a teat cup liner

pulsatir

the part of the milking system that causes the alternate vacuum pressure between the teat cup shell and liner

residual milk

milk remaining in the mammary gland following completion of milking

ropy milk

milk that contains strings of white blood cellssan

sanitizer

chemical solution used to kill bacteria on product surfacesso

somatic cell count

Measurement most used as an indicator of mastitis; an indicator of the extent of subclinical mastitis present in a cow's udder or number of leukocytes present

subclinical mastitis

Mastitis with no detectable change in the udder itself and no observable abnormality in the milk 

wash line

Line that carries cleaning and sanitizing solutions during the cleaning process from the wash sink, vat, or tank to the milking units, milk line, or milking vacuum line

acid degree value

test that detects rancidity in milk

casein

the primary protein found in milk

churning

process that turns cream to butter

cream

high fat milk product separated from milk

homogenization

a process by which the fat droplets from milk are emulsified and the cream does not separate

lactase

enzyme needed by humans to digest lactose

lactose

milk sugar that gives milk its sweet flavor

pasteurization

process that destroys any diseas-producing bacteria that might be present in raw milk

raw milk

milk as it comes from the cow prior to processing

rennet

substance containing many enzymes that is obtained from the lining of a calf’s stomach

rennin

Enzyme found in rennet that is used when making cheese

separation

process of dividing milk into skim milk and cream

standard plate count

test that measures bacterial content of raw milk to monitor milk quality

whey

fluid by-product of cheesemaking

fluid milk

packaged dairy products used as beverage milks

fluid products

term traditionally used to define products including beverage milks, fluid cream items, and yogurt

milk class

describes how milk is used by the processor or in a marketing area

anestrus

Failure to have an estrus cycle 

artificial insemination

Process of freezing semen from a bull and thawing it later to fertilize ova 

calving interval

Period from one calving to the next calving, usually measured in months 

conception rate

Percent of services (breedings) that result in a pregnancy 

corpus luteum

temporary gland that forms on the ovary after the ovum is released; also called the yellow body

days open

Days from calving until conception or successful breeding date 

days to first service

Days from calving until first breeding date 

embryo transfer

Process of removing a fertilized ovum from a donor cow and transferring it to another cow or heifer

estrus

Period of heat in dairy cattle 

fertilization

Process of joining an ovum and a sperm. Takes place in the oviduct

freemartin

Sterile heifer born twin to a bull 

gestation

period of pregnancy; it begins at fertilization and ends at birth

inferitility

Describes the animal that is neither normally fertile nor totally sterile 

metritis

Infection of the uterus 

ovulation

Process of releasing an ovum from the follicle on the ovary 

parturition

Act of giving birth (also called calving, freshening)

sterility

describes the animal that cannot reproduce

gene

the basic unit of inheritance

genomics

the study of genes or gene products in an organism

genotype

genetic make-up of an individual

heritability

Measure of the percent of phenotypic differences between animals for a single trait that can be transmitted to offspring 

pedigree

a record of ancestry

phenotype

The observed trait of an individual resulting from the effects of the genotype, the environment, and their interaction 

predicted transmitting ability

Measurement of average superiority or inferiority that will be transmitted to an offspring 

purebred

a dairy animal whose sire and dam of the same breed are registered or who are eligible to be registered in a herdbook

antibiotics

Chemical agents given to animals that kill or stop the growth of bacteria 

antibodies (immunoglobulins)

Proteins synthesized by organs of the cow's immune system that aid in the elimination of foreign substances such as microorganisms

balling gun

Instrument used to give an animal a pill or bolus 

biosecurity

Management practices that protect the herd from the entry of new diseases and minimize the spread and adverse effects of diseases in the herd

disease

A change in the normal state of the body, or one or more of its organs, which disturbs the proper performance of body functions 

erythrocytes

Red blood cells; only cells that have no nucleus 

morbidity rate

Number of sick animals during a specified period 

mortality rate

Number of dead animals during a specified period 

pathogen

Any microogranism that causes disease 

physiology

Branch of biology that deals with the process, activities, and phenomena of life and living organisms

toxin

Poison produced by microorganisms that kills cell s

zoonoses

Diseases and infections that are transmitted between vertebrate animals and human beings