Industry terms and definitions
These definitions and associated formulas have been developed to provide national standards for performance comparison.
Where a definition states 'over a given period' the period must be stated, such as daily gain from birth, or daily gain from 50 kg.
The breeding herd
- The observed production of foetuses between services and up to, and including, the 109th day of pregnancy.
- Age of gilts mated (average)
- The total age in days of gilts, at mating, divided by the number of gilts (approximately 7 to 8 months).
- A male pig castrated before puberty.
- Any male pig over 6 months and intended for use in the breeding herd.
- Conception rate
- The number of sows that conceive to service expressed as a percentage of these services. Conception is assumed by non-return to oestrous 21 days after service, or identified by pregnancy diagnosis at about 30 days post-service. These measures are not precise and the term 'conception rate' is therefore of limited use.
- Condition scoring
- A method of estimating the fat cover on sows so that feeding levels can be determined.
- Culled sow or boar
- (a) Any live sow or boar removed from the breeding unit.
- (b) Culling percentage =
total number of sows and boars sold and transferred x 100
average number of sows (see 'herd size') and boars
- Empty days
- The number of days between weaning or sows initial service and effective service or removal from the breeding herd.
- Empty days (herd average)
- (365 ÷ herd farrowing index) - (herd lactation length + 114)
- Failure to farrow
- Sow not farrowed by 120 days after presumed effective service.
- Production of a litter of one or more live or dead pigs, but not abortion.
- Farrowing index (herd) or litters per sow per year
- The number of farrowings taking place in a given period, expressed on an annual basis, divided by the average number of sows in the herd during the period when those sows were mated.
total number of farrowing
average number of sows (see 'herd size'), at time of mating
x 365 days days in period
- Farrowing interval
- The number of days from one farrowing to the next farrowing.
- Farrowing rate
- The number of sows that farrow to a given number of services expressed as a percentage.
total number farrowed x 100
total number sows mated during the period
- Full-term empty
- Sows that go full-term, presumed pregnant, and do not farrow.
- Gilt or maiden gilt
- A female transferred to the breeding herd but not yet mated.
- Gilts: Average age mated
- The total age in days of gilts when mated divided by the number of gilts.
- Gilt wastage
- Gilts intended for breeding and not served divided by gilts served in the same period expressed as a percentage. (This can be 25% higher in summer)
gilts not served x 100
total gilts selected (i.e. served and not served)
- Herd size
- The total number of sows in the herd.
- Herd size (average)
- The average number of sows present in the herd over a defined period of time.
number of sows at start of period (e.g. month) + number of sows at end of period
number of counts (e.g. one each month)
- Describes the behaviour of a sow when on heat (during oestrous).
- The deposition of semen into the reproductive tract of a sow exhibiting oestrus.
- Not in pig. Sows that go full-term (presumed pregnant) and do not farrow.
- The number of litters a sow has carried (including current pregnancy), e.g. a second parity sow is in pig with or suckling her second litter.
- Reproductive cycle
- Days from the conception of one litter to the conception of the following litter. Not the same as parity.
- Return to service
- A sow re-served after a previous unsuccessful service.
- (a) One or more observed matings within the same oestrus period.
- (b) Service date: date of first mating during any one oestrus period (counted as day 0).
- Service index
- The number of services taking place in one year divided by the average herd size.
- Any breeding female that has been served and is on the farm.
- Sow mortality (percentage)
total number of sows died x 100
average number of sows in the herd (see 'herd size') over a given period
- Sow to boar ratio
- The ratio of sows to boars as defined. This must take into account the non-working boar.
- A male pig castrated late in life, (that is, an old boar after castration).
- Weaning to service interval
- The interval between date of weaning and the date of first service (date of weaning = day 0).
- A management practice involving fostering piglets to benefit sows and litters.
- The act of transferring a sucker or suckers from one sow to another.
- Lactation length (average days) or weaning age
- The sum of lactation days in a given period divided by the number of sows weaned in that period.
total lactation days
total number of sows farrowed
- The product of a farrowing.
- Litter scatter
- An index indicating herds with numbers of pigs born per litter to one standard deviation above and below an average litter size within any specified period.
- Litter weight variability
- The range of weights at birth.
- Litter weight at birth
- (a) Total weight: the weight of all suckers in a litter (kg), born alive within the first 24 hours, including those that died before weighing.
- (b) Average weight: the sum of total litter weights (as above) of piglets born alive within the first 24 hours divided by the total number of suckers weighed, including those that died before weighing.
- Litter weight at weaning
- (a) Total weight: the total weight of piglets (kg), that were weaned from one litter.
- (b) Average weaning weight:
- Piglets: total litter weight at weaning divided by the number of piglets in the litter.
- Litters: total weight of litters at weaning divided by the total number of litters weaned.
- Litters per sow per year
- See 'farrowing index'.
- The number of litters a sow has carried (including current pregnancy) e.g. a second parity sow is in pig - suckling or has just weaned her second litter.
- Pigs born alive
- The number of piglets born alive (excluding stillborn and mummified pigs) per farrowing.
- Pigs born alive per litter
total number of piglets born alive
total number of sows farrowed
- Pigs born alive per sow per year (average)
- The number of piglets born alive per sow in a given period expressed on a yearly basis, divided by the average herd size at mating.
total number of piglets born alive
sows on hand (see herd size) at time of mating
x 365 days days in period
- Pigs born per sow per year (total)
- The total number of piglets born (alive or stillborn), excluding mummified pigs, per sow in a given period expressed on a yearly basis divided by the average herd size at mating.
- Pigs born dead (total stillborn)
- The number of piglets presumed to be dead at birth, when first inspected, that are fully formed at farrowing (excluding mummified piglets). If necessary, confirmed by post mortem examination to determine if the piglets have breathed.
- Pigs born dead per litter (average stillborn)
- The total number stillborn piglets divided by the number of farrowings over a given period.
- Pigs born per litter (total)
- The total number of piglets born (alive or stillborn) per farrowing, excluding mummified pigs.
- Pigs mummified
- Number of dead piglets (foetuses) that are born degenerate (discoloured and shrivelled). That is, they have died some time before farrowing.
- Pigs weaned per litter (average)
- The average number of pigs weaned over a given period divided by the number of sows that farrowed in that period.
total number of piglets weaned
number of sows farrowed
- Piglets weaned per sow per year (average)
- The total number of piglets weaned in a given period, expressed on a yearly basis, divided by the average number of sows ('herd size') at the time of mating.
total number of pigs weaned
average number of sows (see 'herd size') at mating
x 365 days days in period
- Pre-weaning mortality
- Percentage: The number of piglets born alive that die before weaning, expressed as a percentage.
(total number born alive - number of piglets weaned from those litters) x 100
total number born alive
- Number/litter: The number of piglets born alive per litter that die before weaning.
number born alive - number of piglets weaned from those litters
number of weanings
- The smallest pig in the litter.
- A pig between birth and weaning.
- The permanent separation of a sow and suckers.
- For statistical purposes all sows that die between farrowing and weaning are deemed to be weaned at the time of death. If all suckers die the sow is recorded as having weaned zero piglets.
- Weaning age (average)
- The average number of days from farrowing to weaning or death (day of farrowing = day 0), in a given period.
sum of sows' lactation lengths
number of sows weaned and died days
x 365 days days in period
Progeny: post-weaning period
- Market pigs between 65 and approximately 80 kg dressed weight. The maximum weight can vary between processors.
- Daily dressed weight gain (group average)
- The total carcase weight of pigs, when slaughtered, divided by the total number of pig days, expressed as grams per day.
total dressed weight of growers sold x 1000
calculated age at turn-off
- Daily dressed weight gain (individual)
- The dressed weight of the pig divided by the number of days from birth, when leaving the farm, expressed in grams per day.
- Daily liveweight gain (group average)
- The total liveweight gain of pigs divided by the total number of pig days, expressed in grams per day.
- Daily liveweight gain (individual)
- The total liveweight gain of the pig, for a specified period, divided by the number of days over the same given period, expressed in grams per day e.g. 500 grams/day (0 to 90 kg), 700 grams/day (40 to 90 kg).
- Feed conversion ratios
- The total weight of air-dry food consumed by a pig or pigs divided by its/their live weight (or dead weight) gain over a given period. This measure can be calculated over different periods of the pig's life or as an average over the whole herd by the formula:
total feed consumed in the period
total gain (a) in the period
- Where (a) in the case of a group of pigs e.g. shed or a herd, is the total weight of pigs sold + total weight of pigs transferred out + total weight at the end of a period - total weight of pigs purchased - total weight of pigs transferred in - total weight at start of period.
- Any pig between weaning and sale or transfer to the breeding herd, sold for slaughter or killed for rations.
- Grower pigs over 70 kg liveweight.
- Pigs reared
- The total number of grower pigs sold or transferred to the breeding herd, including those killed for rations.
- Pigs reared per sow per year
- The total number of pigs sold plus the total number transferred to the breeding herd, divided by the average herd size.
growers + suckers on hand @ end) + sales + replacements
- pigs purchased - (growers + suckers on hand @ start)
average number of sows days
x 365 daysdays in period
- Market pigs between 30 and about 54.5 kg dressed weight.
- Post-weaning mortality
- The number of growers that die expressed as a percentage of the total number of pigs weaned that produced those growers, over a given period.
total number of grower deaths x 100
total number of pigs weaned
- Pigs between two and three months of age or 20 to 40 kg liveweight.
- Any pig between weaning and either eight weeks of age or 20 kg liveweight.
- Age at slaughter (average)
- The average age in days of grower pigs leaving the farm for slaughter (birth = day 0), excluding those that die.
- Culled breeding pig sold for meat; usually refers specifically to a culled sow, but is sometimes used in reference to boars.
- The sale of any sow, boar or gilt for breeding purposes.
- A condemned carcase either wholly or in part.
- Dark firm and dry pork (DFD)
- Meat in which muscles are dark in colour, may be sticky and holds water well.
- Deaths in lairage
- Any pig dying between the end of unloading at the abattoir and up to the point of slaughter.
- Deaths in transit
- Any pig dying in transit between the end of loading at the farm and the end of unloading at the abattoir or final disembarkation point.
- Dressed weight at slaughter (average)
- The total weight dressed weight of pigs slaughtered divided by the number of pigs slaughtered. This measure is usually calculated for different classes of stock.
- Grower pigs sold
- Any grower pig that leaves the farm that is categorised by weight. Different marketing systems use different weights.
- Grower pigs transferred
- Any grower pig that is killed for rations or transferred to the breeding herd.
- Liveweight at slaughter (average)
- The total live weight of pigs leaving the farm divided by the number of pigs leaving the farm (include deaths in transit and lairage).
- Meat sold per sow
- The total dead weight sold divided by the average number of sows ('herd size') in a given period.
- Other pigs sold
- All other market pigs sold, such as weaners and own rations, but excluding porkers, baconers, culled sows and boars (backfatters/choppers).
- Percentage prime
- The number of pigs slaughtered that are graded prime (or first grade), expressed as a percentage of total pigs slaughtered.
total number of prime pig carcases x 100
total number of pigs slaughtered
- Price per kg meat sold (average)
- The total returns received from pigs in a given period divided by the total dressed weight sold in the period. This measure can be calculated for different classes of pigs (e.g. pork bacon) or averaged over the whole herd:
total returns from pigs sold ($)
total dressed weight sold (kg)
- Standard carcase
- The dressed weight carcase is the whole body of a slaughtered pig, passed as suitable for human consumption by a meat inspector after bleeding, removal of hair, scurf, toenails, ears eyelids/lashes, tongue, kidneys and kidney fat, and evisceration of all internal, digestive, respiratory, excretory and reproductive organs.
- Soft exudative pork (SE)
- Meat in which muscles are paler in colour than normal, with a soft texture and wet surface, often with high drip loss, and a pH below 5.6.
Feeds, feeding and nutrition
- Ad libitum (Ad lib) feeding
- Feed offered continuously, without restriction.
- Usually by-products of a manufacturing process, such as grain or meat processing (pollard, soybean meal, meatmeal and biscuit meal) that can be satisfactorily fed to pigs, providing any nutritional requirements are met with other ingredients.
- Breeder feed
- Diets that are fed to boars sows and gilts.
- Breeder feed per day (average) kg
- The total breeder feed (dry and lactating sow feeds) used, taking into account inventory change, divided by the average number of breeders on hand for the period and divided by the number of days in the period.
breeder feed used (kg)
average number of breeders x days
number of days
- Controlled feeding
- See 'restricted feeding'.
- Cost of feed per kg (average)
- Total cost of feed purchased divided by the total of feed purchased (kg) in a given period.
- Feed that is given to the animal to consume, whether as a single feedstuff or as a mixture of feeds. Not ration.
- Diet: creep
- Highly palatable, easily digested feed offered to piglets while suckling, and for the first week post-weaning.
- Diet: dry sow
- Maintaining condition is the main purpose of this diet, and while protein content can be low, it is still needed to restore some condition. The diet can be flexible, as it is determined by the amount of feed offered. Dry sows can adapt to large amounts of bulky feed. Specifications could be 13.0 MJ DE and available lysine/DE of 0.4g/MJ.
- Diet: finisher
- A diet for finisher pigs that keeps daily energy consumption within the range of 32 to 36 MJ DE from an energy density of 13.2 to 13.5 MJ DE/kg and with an available lysine/DE ratio of about 0.5 to 0.55 g/MJ. There may be a number of diets fed during this stage to more closely match the pigs' nutrient needs (phase feeding) and there may be separate diets for male and female pigs.
- Diet: grower
- This is the stage of rapid lean growth so the diet needs high energy (14.0 MJ DE/kg) and protein (available lysine/DE ratio of about 0.68g/MJ) diets.
- Diet: lactating sow
- A diet for suckling sows that delivers nutrients to support herself and her litter and minimise loss of weight. Normal specifications are 14.0 MJ DE and available lysine of 0.55g.MJ.
- Diet: weaner
- This diet needs to cater for the digestive ability and capacity of the young pig (approximately four weeks of age) and its high potential lean growth rate and be cost effective for the usual six weeks that it is fed. This requires a high nutrient density and normal specifications are 14.5-15 MJ DE/kg and 0.75-0.8 available lysine/MJ DE.
- Feed cost ($) per kg of meat produced
- The total cost of feed used divided by the total deadweight of pigs sold in a defined period, taking into account inventory changes of feed and estimated dressed weight of pigs on hand.
- Feed efficiency (see 'feed conversion')
- An important measure of overall pig production efficiency. Whole herd feed efficiency refers to the total amount of feed (including breeders) required to produce each kg of meat on a live or dressed weight basis.
- Feed used per sow
- The total amount of feed used for all breeders (+ & - inventory changes) divided by the average number of sows ('herd size') in a given period.
breeder feed used (kg)
average number of sows (see 'herd size')
- Joule (J)
- Metric unit of energy; 4.184 J = 1 calorie.
- The requirements of the animal for nutrients for the continuity of vital processes, within the body, including the replacements of obligatory losses in faeces, urine and skin, are met, so that the net gain or loss of nutrients and other tissue substances by the animal as a whole is zero.
- Ration (scale feeding)
- Refers to the weight of complete diet offered daily and is not confined to energy intake; it may be given either in a single portion or in a number of portions each day. When the level of feeding is increased, daily intakes of all nutrients are thus increased.
- Restricted feeding
- Feeding systems where the feed is rationed to an individual pig or group of pigs and is under the daily control of the person feeding the pigs. Amounts given are usually restricted to less than the pigs' maximum voluntary intake at each feed and are most commonly given once or divided equally into a number of portions, each day. The feed may be given either wet or dry. Same as controlled feeding.
- Scale feeding
- See 'ration'.
- Critical temperature
- Lower (LCT): the lower temperature limit of the pigs thermal comfort zone. Pigs start to huddle. Heat loss is increased with less energy available for growth and production.
- Evaporative (ECT): the temperature at the upper limit of the thermal comfort zone at which the pig starts to pant to increase the evaporative heat loss from its lungs. A good measure is 50 to 60 breaths per minute. Pigs appetite is suppressed, with reduced growth rates and reproductive performance and depressed feed efficiency.
- Upper (UCT): the temperature at which the pig's evaporative heat loss from lungs and skin is greatest and has no further mechanisms left to control its rising body temperature.
- Gross margin
- Total income from all pig sales minus the cost of pigs purchased, minus total feed and other variable costs, plus or minus the livestock inventory change in a given period.
- Halothane test
- There are two methods of determining 'halothane gene' stress susceptibility in pigs:
- Pigs at about eight weeks of age are anaesthetised by administration of halothane/oxygen mixture through a face mask for three minutes. Pigs remaining relaxed are negative reactors. Pigs whose hind legs become rigid are positive reactors.
- A blood test detects whether the pig carries one or both genes that make pigs more prone to stress.
- Hybrid vigour - the lift in performance of pigs produced by crossbreeding. This is mostly in reproductive traits.
- Inventory change
- The change in inventory is the difference in value and/or number of pigs on hand at the beginning and the end of a given period. All stock on hand at the beginning and end of the period must be valued at the market prices (relevant to each class of livestock and/or by the average weight of pigs on hand) at the time of the stocktake. The difference in value will be positive or negative, depending on the changes in numbers of pigs over the period.
- Where pigs are held after unloading at the abattoir and up to the point of slaughter.
- Porcine stress syndrome (PSS)
- Marked susceptibility to stress in pigs; a heritable genetic trait observed by use of the halothane tests. Affected pigs have higher incidence of stress death and SE pork, poorer growth rates, lower appetites and smaller litters, when compared with normal pigs.
- Thermal comfort zone
- The temperature range at which a pig feels most comfortable. See 'critical temperature'.
- Unit costs of production
- The total cost (including fixed overheads) of producing one unit (e.g. pig meat, pig).