Expression of estrogen receptors alpha and beta in the corpus luteum and uterus from non-pregnant and pregnant llamas.

Because estrogen may be involved in maternal recognition of pregnancy and embryonic migration in llamas, expression of estrogen receptor subtypes alpha (ERalpha) and beta (ERbeta) was evaluated in corpus luteum (CL), endometrium, and uterus using relative RT-PCR. Tissues were recovered from sterile-mated (SM) and pregnant (PG) females during Days 7-11 and 7-13 (Day 0 = day of mating), respectively, and follicular phase and juvenile females. Luteal expression of ERalpha and beta was similar (P > 0.

Estradiol production by preimplantation blastocysts and increased serum progesterone following estradiol treatment in llamas.

Estradiol is a potential candidate for the blastocyst signal responsible for maternal recognition of pregnancy in the llama (Lama glama). Two experiments were conducted to determine if the llama blastocyst produces estradiol during the presumed period of maternal recognition of pregnancy and if exogenous estradiol can extend the luteal phase. In Experiment 1, llamas were superovulated with eCG and mated 7 days later (Day 0=day of mating).

Seasonal interaction of serum vitamin D concentration and bone density in alpacas.

Objective: To evaluate temporal changes in bone mineral density associated with seasonal variation in serum vitamin D, calcium, and phosphorus concentrations in alpacas.

Animals: 5 healthy mature neutered male alpacas.

Procedure: Metacarpal bone mineral density was measured at 4 times during a year.