B18: . Reproduction features, reproduction, prolificacy and fertility traits, most important genetic diseases of goat Flashcards
reproduction traits of goats:
puberty
full breeding maturity
sexual activity
breeding season
biostimulation
Puberty: 6-8 months
Full breeding maturity: 8 months
Sexual activity: Breed dependent 🡪 Seasonally polyoestrus (continental climate; Sept-Feb.8-10 cycles) or continuous breeding (tropical).
Breeding season: August-November (longer), Jan-Feb (short period). Highest fertility Sept, Oct, Nov.
Biostimulation: Role of sexual pheromones is important (teaser rams etc.)
oestrus of goat:
length
ovulation
mating /AI
symptoms
heat detection
Length: Nanny goat — 19-23 days
- Ovulation: Spontaneous, 1-4 eggs per ovulation.
- Mating/ AI: Prior to ovulation, Artificial Insemination→ Laparoscopic (low success rates).
- Twinning and multiple births are common desirable traits, fecundity genes (FecB, FecX)
symptoms: not well expressed; small vaginal discharge, hyperaemia
heat detection: behaviour, male acceptance, standing, teasing
is lactation anoestrus common in goats?
yes
What gene mutations can occur in sheep and goat?
Fecundity/fertility gene mutations in sheep: (on autosome 6 and X chromosome)
gestation in goats:
length
location of fertilisation
Pregnancy: 145-150 (147) days
- Fertilization occurs in Fallopian tube & migrates to uterus on day 3-4
implantation: Centric, early (14-15 days)
pregnancy detection methods in goats
◦ Easy
◦ Abdominal palpation from day 90
◦ Ultrasonography
length of lactation in goats
- Lactation: 100-300 in goat
What are the reproductive traits of a doe (nanny goat).
seasonality
cycle interval
pseudopreganncy
prolactin role
lactation
environmental factors
fertility
- Pronounced seasonality (from August to February) in both sexes (seasonal anoestrous is typical).
- Cycle interval: 20-21 days, heat signs are lively, more expressed and longer heat, more expressed and longer heat(36-56 h), ovulation 12-36h after heat onset.
- Prolactin plays a distinct role 🡪 Luteotropic effect (maintenance of pregnancy & lactation etc).
- Pseudopregnancy is known in does:
o signs; Persistent corpus luteum, uterine secretion, lactation “cloud burst”. - Lactation anoestrus is typical: Autumnal weaning of kids has a synchronizing effect with heat occurring within a week.
- Goats show less breed variance, breeds more unified.
- Environmental factors are highly effective: strong biostimulation (sex-pheromones of bocks), photoperiod dependence and sensitivity are high.
- Goats’ fertility are higher: twins up to 50-60% triplets and multiple births are rare.
what are important genetic disorders related to circulation in goats?
- Hyperbilirubinemia I et II
- Glutathione-deficiency anaemia
- Haemophilia A (XL, factor VIII)
what are important genetic disorders related to metabolic (lysosomal storage disease) in goats?
- Ceroid lipofuscinosis
- Gangliosidosis I
- Gaucher and Krabbe disease
- Glucogenosis II & V
- Mucopolysaccharidosis IIID (goat)
- Mannosidase alpha and beta (goat)
what are important genetic disorders related to fat metabolism in goats?
yellow fat (recessive)
what are important genetic disorders related to muscle in goats?
- Muscular dystrophy
- Myotonia congenita (wooden-leg or faint goat breed)
what are important genetic disorders related to bones in goats?
- Chondrodysplasia, achondroplasia
what are important genetic disorders related to intersexes in goats?
XX males
what are important genetic disorders related to circulation in goats?
