Swine Production Lecture 10 and 11 - Replacement Gilts/Reproduction

within herd

Where most replacement gilts are found

well-developed underline

sound feet/legs

fast growing

from large litters

from high producing mothers

guidelines for selecting replacement gilts

structural soundness

volume/body capacity

muscling

leanness

underline quality

visual evaluation for replacement gilt selection

number born alive (NBA)

number of offspring born in a litter

expressed as number of individuals

10% heritability

21 day litter weight

weight in pounds adjusted to 21 days

15% heritability

maternal line index

index which includes TSI and maternal traits (SPI)

BF, Days, LBS, NBA, LWT, NW

maternal traits weighted 2x as much

sow productivity index

index which includes NBA, LW, and NW

indicates reproductive ability

based on average (100)

HAL gene

porcine stress syndrome

pigs have PSE pork

originally selected for lean meat

ESR gene

estrogen sulfate receptor

increased ovulation rate

K88 gene

- e. coli binds to the K88 receptor in gut

- no K88 = no e. coli = no scours

white skin

trait that packer prefer

5-8 months

180 lbs

age and weight of puberty

2-3 days

length of estrus

20-22 days

length of estrous

12 hrs before end of estrus

time of ovulation

114 days

length of gestation

3-7 days

amount of time post-weaning that cycling occurs again

level of fatty acids

level of carbs

level of leptin

factors that may affect onset of puberty

boar exposure

PG600

technique to bring prepubertal gilts into heat

Matrix

oral progesterone fed for 14 days to synchronize cycling females

group weaning

technique used to synchronize weaned sows

suckling

releases opioids that inhibit GnRH release --> prevents cycling