O
OB Sleeve:
A long, thin plastic glove worn over the veterinarian’s hand and arm
Obesity:
Excessive accumulation of body fat
Obliquus Abdominis Externus:
A muscle that originates from the last few ribs and extends posteriorly and ventrally to the flank region
Obliquus Abdominis Internus:
A muscle that originates near the last rib and extends anteriorly and ventrally to the flank region. Where both the obliquus abdominis externus and internus are present, it is medial to the externus
Obsessive Compulsive:
A behavioural condition in which a pet repeatedly performs an action out of context
Occipital Bone:
The bone which forms the back and base of the skull
Occipital Foramen:
That part of the occipital bone that encircles the spinal cord
Occulation:
(see Bite)
Occult:
Refers to a structure or process that is hidden or detected indirectly
Ocular:
Pertaining to the eye
OD:
Optical Density
OECD:
Organisation for Economic Co-operation and Development
Oedema:
The medical term for fluid retention in the body, causing swelling to occur in the affected area
Oedematous:
Affected by oedema
Oesophagus:
The part of the intestinal tract between the mouth and stomach
Oestradiol:
The main oestrogen produced by the ovary
Oestrogen:
Hormone produced by the ovary responsible for the development of female sexual characteristics. It is responsible for the signs of heat
Oestrus:
Period of sexual receptivity
Offal:
The edible organs or parts from the thoracic and abdominal cavities and the tongue
Off Feed:
Animal refuses to eat or consumes only small amounts of feed
Off Label:
Refers to a drug prescribed to treat a condition for which it has not been approved. Off-label use of a drug must be determined by the attending veterinarian
Offspring:
Progeny or young
OFMVS:
On - Farm Market Valuation Service
OIE:
International Office of Epizooties
Oilseeds:
Crops whose seeds contain large quantities of oil. E.g. Soybeans, sunflower seed, canola, rapeseed, safflower, mustard seed, and flaxseed
Ointment:
An externally applied medication in a semisolid base
Okie’s Choice 1’s:
An animal that is predominately Hereford, Angus, or Black Baldy or out of an English breed type of cow. The number 1 refers to thickness (muscling)
Oligonucleotide:
A short length of nucleic acid composed of between two to approximately 10 nucleotides
Oligopoly:
Market in which there are only a few sellers of a product or service so that each will be affected substantially by a change in policy on the part of another
Omasum:
One of the stomach components of ruminant animals that have many folds
On Feed:
Cattle on a managed feed program designed to increase their rate of gain to the proper finished weight
On Full Feed:
Refers to cattle that are receiving all the feed they will consume. See also ad libitum
On Set:
In medicine, the first appearance of the signs or symptoms of an illness
On the Hoof:
Designating a living meat animal
Oocyte:
A female germ cell in the process of development. The oocyte is produced in the ovary by an ancestral cell called an oogonium and gives rise to the ovum (the egg) which can be fertilised
Oocyte Pick Up (OPU):
An assisted breeding technique where oocytes are collected from follicles using a fine needle and suction. Embryos for transfer are then produced by in vitro maturation, fertilisation and culture
OPD:
Orthophenylene diamine
Open:
A term commonly used to indicate a non-pregnant female
Open Barn:
(see Loose Housing)
Open Show:
Shows that are open to exhibitors of all ages; shows that are open to all breeds
Open Side:
The left side of a beef carcass. So called because of the longer and freer attachment of the kidney and surrounding fat
Openness:
A quality in dairy cattle associated with length of body and width and length of rib
Operating Costs:
(see Operating Expenses)
Operating Expenses:
Expenses incurred in the usual production cycle, such as seed, fuel, feed, and hired labour costs
Operation:
Business entity, typically comprised of one or more parcels of land
Opioid:
A synthetic narcotic that resembles naturally occurring opium
Opisthototonos:
Spasm of the muscles causing backward arching of the head, neck, and spine, as in severe tetanus, some kinds of meningitis, and strychnine poisoning
Opportunity Costs:
Cost of using a resource based on what it could have earned using it in the next best alternative use
Optic Nerve:
The second pair of cranial nerves, transmitting impulses from the brain to the retina
Optimize:
To make as effective as possible
Optimum:
Amount or degree of something that is most favourable to some end (e.g., the best combination of resources associated with cattle production yields the highest sustainable net return)
Optimum Level of Performance:
The most profitable and favourable ranges in levels of performance for the economically important traits in a given management system and environment. For example, although many cows produce too little milk, in every management system there is a point beyond which higher levels of milk production will reduce fertility and decrease profit
Oral:
Placement of a drug or other substance into an animal through its mouth
Oral Vaccination:
Usually by consumption by a target species of a bait containing vaccine
Orchitis:
Inflammation of the testis
Ordinal Scale:
A number which defines a thing (trait) in a standard scale
Oreana:
Another term used for a lone unmarked and unbranded calf
Orexigenic:
Causing appetite enhancement
Organic Beef Product:
A form of farming that emphasises the soil – plant – animal complex, and utilises manures and composts free of synthetic chemicals
Organic Material:
Substances containing plant or animal substance. In the context of milking equipment, this usually refers to manure
Organic Milk:
Milk and milk products can be labelled “USDA organic” if the milk comes from farms that meet USDA’s National Organic Program standards. Organic milk is just one of many options in the dairy case to fit different lifestyles and personal preferences
Organism:
An individual animal, plant, or single-celled life form
Organogenesis:
The production of organ systems during animal embryogenesis
Organoleptic:
Making an impression on, or stimulating, any of the special senses: smell, sight, taste, and touch
Oriface:
The opening at the end of a functional teat
OS:
Ox Serum
OSD:
Optimal Sensitising Dose
Osmolality:
The osmotic conception of a solution, which can be measured by osmotic pressure
Osmoreceptors:
Specialised nerve cells in the gut that respond to changes in the osmolarity of the ingesta
Osmotic Pressure:
A chemical force caused by a concentration gradient. It is a colligative property and the principle behind membrane processing
Ossification:
The formation of bone or a bony substance; the conversion of fibrous tissue or cartilage into bone by the deposition of hard mineral material, especially calcium and phosphorus. Note: This concept is especially important in determining skeletal maturity
Osteochondrosis Desiccans (OCD):
A disease-causing inflammation and damage mainly to the stifle, carpus, tarsus and shoulder joints. The disease is more prevalent in animals fed diets that induce high growth rates
Osteomyelitis:
Term to describe an infection of the bone or bone marrow
OTC:
Drugs and other substances that can be bought by anyone over the counter because adequate instructions for safe and effective us by laymen can be printed on the label
OTF:
Officially Tuberculosis Free
Other Feeds:
Feeds fed on a group basis that are under 50% TDN or cost under $100 per ton. These may include blended rations
Other Succulents:
Any relatively high moisture forage feed that is not considered to be silage
Otic:
Relating to the ear
Ototoxic:
Damaging to the structures of the ear
Out Of:
Terminology for mothered by in animal breeding
Outbreeding:
Mating of animals less closely related than the average of the population
Outcrossing:
Mating of individuals that are less closely related than the average of the breed. Commercial breeders and some purebred breeders should be outcrossing by periodically adding new sires that are unrelated to their herd. This outcrossing should reduce the possibility of loss of vigour due to Inbreeding
Ova:
Plural for Ovum
Ovariectomy:
The surgical removal of an ovary
Ovariohysterectomy:
(see Spayed)
Ovary:
The female reproductive gland in which the eggs are formed and progesterone and estrogenic hormones are produced
Over - Resting:
Prolonged lack of defoliation of plants or non-disturbance of plants and soil
Over – the – Hooks (OTH):
A term which describes cattle being sold directly to the processor with payment based on objective carcass measurements post-slaughter
Over the Counter Drugs:
Medications available without prescription
Overconditioned:
An animal with excess flesh and patchy fat deposits, especially over the shoulders, back, hips, and thighs
Overdominance:
A form of dominance where the performance of the heterozygote exceeds that of the best homozygote
Overgrazing:
Repeated grazing of plants before recovery of root energy reserves
Overhead:
Expenses incurred in the operation of the business that cannot conveniently be attributed to the production of specific commodities or services
Overeating Disease:
A toxic condition caused by the presence of undigested carbohydrates in the intestine, which stimulates harmful bacteria to multiply. When the bacteria die, they release toxins. Called enterotoxaemia in some animals
Overmarking:
Small black spots that appear on an otherwise all white animal
Overshot Jaw:
The upper jaw is longer than lower jaw. Also, called parrot mouth
Overstocking:
Placing a number of animals on a given area that exceeds the forage supply during the time they are present
Ovulate:
The release of an egg from the ovary of the female
Ovulation:
The release of the female germ cell (egg or ovum) by the ovary. Cows usually ovulate several hours (up to 15 hours) after the end of estrus or standing heat
Ovum:
Single unfertilized female egg cell containing half the normal chromosomes
Ovum Pick Up Technique (OPU):
Collection of eggs from donor through an ultrasonically guided needle inserted into the ovary
Ox:
Oxen, usually cattle trained to work as draught animals
Oxtails:
The tails of beef carcasses. The coccygeal vertebrae and associated muscles
Oxymyoglobin:
The oxygenated form of myoglobin that exhibits a bright cherry colour. The iron in the heme ring is in a reduced form
Oxytocin:
A naturally secreted hormone that is important in milk letdown and the contraction of the smooth uterine muscles during the birthing process
Oyster:
Connective tissue and fat lies on the medial side of the aitch bone