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?
what are important genetic disorders related to endocrinology in goats?
*proportional dwarfism (STH receptor mutation) *goitre (goat)
what are important genetic disorders related to skin and hair in goats?
- Albinism
- Dermatosparaxis (skin ashthenia)
- Eptheliogenesis imperfecta (partial lack of skin)
