GLOSSARY OF SHEEP TERMS CONTINUED FROM PREVIOUS PAGE
FITTED – A sheep shown with a washed, trimmed, shaped, packed and sculpted fleece. FLOCK - A group of sheep. FLOCK IMPROVEMENT - The means by which an individual breeder implements selection and mating strategies to align their flock with their personal goals and/or marketing plan. These plans differ among breeders and provide for genetic diversity in the gene pool. FLUSHING - Increasing nutrition prior to and during the early part of the breeding season to improve ovulation, conception and implantation that potentially increases lambing percentage. FOOT ROT - Contagious disease of the hoof which can cause severe lameness. GENETIC IMPROVEMENT – Identifying, measuring, selecting and mating for traits that will improve productivity and profitability. GENOMICS – a branch of biotechnology associated with gene mapping (describing the genes that make up a sheep). GENOTYPE - the genetic make- up of an individual. GENOTYPING - the process of finding differences in the genetic makeup of individual sheep in their DNA sequence. GESTATION LENGTH - The length of pregnancy, usually around 148 days in Suffolks. GRID - Tool used to measure the surface area of the loineye muscle between the 12th and 13th ribs in a lamb carcass. HALF-SIBS - Individuals who have the same sire or dam. HEIGHT – Height of the animal at the point of the shoulder measured from the ground. HEREDITY - The transmission of characteristics from parents to their offspring through genes.
HETEROSIS OR (HYBRID VIGOR) - The increased performance of crossbreds as compared to the average of the parental breeds for specific traits. Heterosis can also occur within purebreds as the result of heterozygosity. HETEROZYGOUS – When two different alleles are present for a particular gene pair (example QR for scrapie resistance susceptibility). HOMOZYGOUS - When both alleles in a gene pair are identical (example RR for Scrapie resistance). HOT CARCASS WEIGHT - Dressed carcass weight immediately after harvest, prior to chilling. JUG - Small portable pen used at lambing where ewes and lambs bond. INBREEDING - Mating of two individuals that are related to each other. Inbreeding is expected to increase the number of homozygous gene pairs and decrease the number of heterozygous gene pairs. Inbreeding may increase the expression of undesirable recessive genes and suppress fitness and growth traits. It can also increase the uniformity and Expressed as a percentage, it is a measure of the amount of inbreeding in an animal’s pedigree. It is the likelihood that two alleles in a gene pair are identical because of a common ancestor of the two parents. LACTATION - Period of time milk is secreted from the mammary glands to feed the animals young. LAMB - A sheep under one year of age. Also refers to the meat or carcass from animals estimated to be under one year of age (break joint vs. spool joint). LENGTH - A linear measurement of a body part (leg, neck, loin) but most often referring to prepotency of a flock. INBREEDING COEFFICIENT –
POST WEANING WEIGHT - Weight taken on a lamb to indicate its growth after being weaned from its dam. NSIP evaluates 120-day post weaning weight as (PWWT). PREPOTENCY - The ability of a sheep to produce progeny that are uniform and predictable in terms of type and expected production. Genetically, prepotency is the result of increased homozygosity and/ or dominance. PRODUCTION TEST - A method of testing a sheep’s ability to perform against a contemporary group. Often this is a group of similarly aged rams tested for their comparative ability to grow rapidly, feed efficiently and/or excel in ultrasound scan data. PROGENY TEST - Evaluation of a sire based on performance of his offspring. Progeny tests can be used to compare multiple sires on the same farm or to evaluate a sire’s progeny across a range of dams, farms and/or environments. PUREBRED - Animal produced from parents of the same breed. QUALITY GRADE – A carcass grade assigned by USDA that indicates acceptability and/or palatability. Determined from measures of maturity (age), flank streaking (marbling), and conformation. Lamb quality grades are prime, choice, good, utility and cull. RAM - Intact (uncastrated) male sheep. RANGE RAM – Rams bred, raised, and selected for their ability to thrive and breed flocks that range over a large given territory in an extensive production system. RATE OF GAIN – A measurement of growth in pounds for a given period of time. RECESSIVE TRAIT – A genetic trait that is only expressed when an animal has two copies of a recessive allele. (example:
length of body as measured from the base of the neck to the pin bone or dock as indicated. LINEAR MEASUREMENTS – One- dimensional measurements that relate to an animal’s size. Examples include height, length, width, or circumference of the animal or its specific parts. LINE BREEDING - A form of inbreeding which increases the average relationship of the individuals in a flock to an outstanding ancestor or line of ancestors, usually several generations back in a pedigree. A given superior animal, for example, might appear several times in a five generation pedigree. LOIN EYE AREA - Cross section area of the loin muscle evaluated between the 12th and 13th rib. Can be measured in live animals with ultrasound or in carcasses with a camera or grid. LOIN - The region of the body between the last rib and the hip bone that contains the longissimus dorsi muscle. Also a wholesale or primal cut from the same location on a carcass. LONGEVITY – An assessment of livability, stayability or ability to thrive productively in the flock over a measurable period of time. MASTITIS - Inflammation of the mammary glands that often results from bacterial infection. MATERNAL DAM TRAITS – Attributes generally associated with ewe productivity such as mothering and milking ability, twinning rate, temperament, fertility (in and out of season) and ewe maintenance cost. MULTIPLE TRAIT SELECTION - Selection for more than one trait at the same time. MUTTON - Meat from a sheep over one year of age. NATURAL SERVICE – A mating that
takes place when a ram breeds a ewe on site in the same location at the same time. NATIONAL SHEEP IMPROVEMENT PROGRAM (NSIP) - The organization responsible for quantitative genetic evaluation of multiple sheep breeds in the United States. OBJECTIVE (QUANTITATIVE) TRAITS – Attributes that are not subject to personal taste or preference but rather a measurable date- driven description. OFFTYPE – An animal that does not meet the breed type standard for a trait or traits. OUTCROSS - Mating of individuals within a breed that are not closely related. OVERBITE - When the lower incisors align behind the upper dental pad. Also known as parrot mouth or undershot jaw. OVINE - The scientific name for sheep. PARASITE – Any number of undesirable vector species that use a sheep as a host (worms, lice, ticks, etc.). PARAMETERS – A set of boundaries within which an ideal or expected pattern is set. PARENT VERIFIED / PARENTAGE TESTING – Genomic confirmation of the sire and dam of a genetically tested animal as determined by DNA. PERCENTAGE REGISTERED - A sheep registered whose lineage is not 100% registered Suffolk. The percentage is noted on the registration certificate (15/16th or 93.75% is currently recognized as a purebred). PEDIGREE – The ancestry of an individual. PHENOTYPE – The observable or measurable expression of a trait. Phenotype results from a combination of genotype and environmental factors.
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