The inheritance of the two types of fleece, Suri and Huacaya, observed in Alpaca (Lama pacos L.) is still not clearly defined. The objective of this work is to investigate the patter of inheritance of these two phenotypes, throughout 588 Suri x Suri and 2126 Huacaya x Huacaya offspring. The single gene and the three two-phenotype epistatic models were tested in the 19 Suri x Suri segregating families. The single dominant gene hypothesis best fitted our segregation data and could be, therefore, accepted (G T =20.276, P=0.378). The gene frequency of the recessive Huacaya allele was 0.295, being the frequency of the dominant Suri allele 0.705. The frequency of heterozygotes, estimated in the whole population and among dominant individuals, was 0.416 and 0.455, respectively, with a "carrier" Suri to Huacaya ratio of 4.780. In three Huacaya families, 3 Suri were born, as a result of a new dominant mutation on some germinal lines of Huacaya animals. The direct mutation rate can be estimated at 0.0014. (G T =20,276, P=0,378). La frequenza genica dell 'allele Huacaya, recessivo, è risultata di 0,295, mentre quella dell'allele Suri, dominante, di 0,705
The objective was to produce alpaca embryos in laboratory due to its potential role for the multiplication of genetically superior animals and for conservation purposes. Ovaries were collected from an alpaca abattoir located in the Central Highlands of Peru and transported in a thermos flask with warm saline and antibiotics to the laboratory located 200 km away on the coast. Alpaca epididymal sperm to be used for fertilization was previously frozen by diluting in a TRIS-Fructose based extender with 10% glycerol and frozen as pellets in liquid nitrogen vapor. From 31 ovaries, 262 cumulus–oocyte complexes (COCs) were collected (mean of 8.5 COCs per ovary) which were matured in TCM-199 supplemented with 10% heat inactivated FCS plus epidermal growth factor (EGF), FSH, LH, estradiol, and cysteamine for 30 h incubation at 38.5°C, 5% CO2 and 90% humidity. The selected oocytes post-maturation were fertilized with the frozen/thawed sperm that was subjected post-thawing to Percoll gradient (90 and 45% Percoll), centrifugation and resuspension in TALP-IVF medium supplemented with 20 μm D-penicillamine, 10 μm hypotaurine, 1 μm epinephrine and 1.1 μg mL–1 of heparin. The oocytes were inseminated with a concentration of 10 × 106 spermatozoa per drop of 100 mL of fertilization medium containing 30 oocytes each and incubated for 24 h at 38.5°C, 5% CO2 and 90% humidity. The presumptive zygotes were transferred to 200 μL drops (30 zygotes per drop) of SOFaa media supplemented with 5% heat-inactivated FCS which was replaced by SOFaa plus 1% heat-inactivated FCS on day 5 after fertilization. The incubation period post-fertilization was up to day 7 at 38.5°C, 5% CO2 and 90% humidity, when the embryos were inspected and graded. The cleavage rate was evaluated at 72 h post-fertilization and embryo development was evaluated on day 5 and 7 post-fertilization. The cleavage rate was 27.1% (71/262) and the percentage of oocytes that reached the stage of morula and blastocyst was 8.0% (21/262). The percentage of blastocyst that hatched when incubated after day 7 was 14.28% (3/21). The in vitro embryo production in alpacas was successful and suggests the possibility for application in intensive reproduction for conservation of South American camelids and for genetic improvement. Research was partially funded by contributions of BIONICHE and SAIS TUPAC AMARU, Junin, Peru.
The objective of the study was to determine the embryo survival up to calving of fresh and cryopreserved (frozen and vitrified) alpaca embryos transferred into alpaca recipients by nonsurgical transcervical embryo transfer and by surgical laparoscopically aided embryo transfer. For this report we have compiled the information from 127 embryo transfers in alpacas done by our group at Mallkini, Puno, Peru, at 4200 m elevation. The embryos have been collected from superovulated donor alpacas flushed at 6.5 days post mating, some were transferred as fresh and some were cryopreserved; the recipients (3 to 7 years old) were selected based on presence of functional corpora lutea at ecosonographic examination and subjected to ovarian cycle synchronization and ovulation induction as per Vivanco (2013). From a total of 133 alpacas selected, 127 were used, from which 82 received fresh, 32 frozen, and 13 vitrified embryos. All embryos were classed as A-class expanded blastocysts at time of transfer. By nonsurgical transcervical embryo transfer, 33 embryos were transferred fresh, 22 were frozen/thawed embryos, and 13 were vitrified/warmed embryos. By surgical laparoscopically aided method, 49 embryos were transferred fresh and 10 embryos were frozen/thawed; no vitrified embryos were transferred by this method. Results are detailed in Table 1. Pregnancy losses occured at up to 9 weeks (63 days) of gestation, the heaviest loss occurs in the first 3 weeks. After 9 weeks of gestation, no losses were registered. In average, 22% of fresh embryos transferred were represented as crias born. None of the cryopreserved embryos survived up to 11 weeks post-transfer. There is no difference in percentage of crias born between nonsurgical transcervical embryo transfers and surgical laparoscopically aided embryo transfers.The heavy embryo losses could be related to nutrition and high-altitude limitations; however, it is difficult to make comparisons with others because reports to date lack information on the actual crias born from embryo transfers in alpacas; most of the reports are based on pregnancy reports up to 30 to 60 days post-transfers. To date, no births from cryopreserved alpaca embryos have been reported. Furher studies on causes of embryo/fetal losses are necessary. Table 1.Results of embryo transfer This study was financed by the Peruvian Fund for Innovation, Science and Technology (FINCYT).
The objective of this study was to compare the effectiveness of cryopreserving in vivo-produced alpaca embryos by slow freezing v. vitrification. The embryos were produced from 9 female alpacas at Fundo Mallkini, Puno, Peru, located at 4300m elevation. The donor alpacas were synchronized by induction to ovulate with an injection of gonadotropin-releasing hormone (0.0084mg of buserelin acetate) and natural mating with vasectomized males to male receptive donors (day of ovulation induction was considered Day 0). On Day 2, the donors were injected 700IU of eCG. On Day 7, the donors received an injection of prostaglandin F2α (0.25mg of cloprostenol) and were mated on Day 8 by fertile males (2 matings 12h apart: 0600 and 1800h). The embryos were collected at 5.5 days after fertile mating and were graded as per IETS recommendations; most of the embryos were already expanded and hatched blastocysts. Embryos were washed and maintained in holding medium (1L PBS+1g Glucose+36mg sodium pyruvate+0.4% BSA+50mg kanamycin monosulfate) at 23°C for up to 1h and distributed into 2 groups for either slow freezing for direct transfer (n=14 embryos) or vitrification (n=10 embryos). Slow freezing consisted of transfer into freezing medium (9mL of 1.5M ethylene glycol+1mL of 1.0M sucrose prepared in holding media) at 23°C, placing in 0.25-mL straws and subjected to freezing at a rate of −0.5°C/ minute to −35°C and then plunging into LN. Vitrification followed a procedure described for camel embryos whereby embryos were exposed to solutions containing increasing amounts of glycerol and ethylene glycol for fixed periods and were then loaded into an open pull straw and plunged directly into LN for storage. The cryopreserved embryos were transferred into adult alpacas at the Community of Suitucancha, Junin, Peru (1500km from the farm where the embryos were collected and cryopreserved, 4200m elevation). Embryos in the slow-freezing group were thawed in warm water at 37°C for 30s and loaded directly into the embryo transfer gun for direct transfer into 7 alpaca recipients (2 embryos per recipient). Vitrified embryos were warmed by removing the open pull straw from the LN and transferring the embryos to 2 warming solutions at 37°C with decreasing levels of vitricants and containing 0.5M galactose with a final incubation at room temperature in holding media and then transferred into 5 alpaca recipients (2 embryos per recipient). The embryos were transferred into synchronized recipients by transcervical nonsurgical method. Pregnancy diagnosis was made by transrectal ultrasound examination at 45 days post-transfer. The pregnancy rates in the slow-freezing and vitrification groups, respectively, were 2/7 (29%) and 0/5 (0%); the difference was not significant (P>0.05) based on Fisher’s exact test. Twin pregnancies were not detected. We consider the result with slow freezing very promising, as in previous trials we had less than 18% pregnancies. More trials with larger number of embryos per cryopreservation method are being programmed.
The objective of the present study was to determine the ovarian response of alpacas to different treatments for follicular development and superovulation. Twenty-nine mature, lactating alpacas, between 31 and 56 days postpartum, managed in the Peruvian highlands (altitude = 4100 m) were randomly distributed into 4 experimental groups. Groups 1 (n = 7) and 3 (n = 8) received a homemade intravaginal sponge containing 60 mg of medroxyprogesterone acetate (MAP; Sigma Chemical Co., St Louis, MO, USA) plus 2 mL of PGF2α (IM; Illiren�; Intervet International, Boxmeer, The Netherlands) on Day 0. Groups 2 (n = 7) and 4 (n = 7) received 2 mL of PGF2α (IM) on Day 0, but did not receive a MAP sponge. All groups received 6 injections (IM) of FSH (Folltropin V�; Bioniche Animal Health, Beltsville, Ontario, Canada) in decreasing dosages of 50, 50, 30, 30, 20, and 20 mg, respectively, every 12 h (at 0700 and 1900 h each day), plus 300 IU of eCG (IM; Folligon�; Intervet International) at the time of the last FSH treatment, with the aim of increasing LH levels. The FSH treatments started on Days 7, 5, 9, and 7 (from Day 0) in groups 1–4, respectively. MAP sponges were removed at the time of the last FSH treatment in groups 1 and 3. All alpacas were naturally mated twice at 12 and 24 h after the last FSH treatment. Alpacas in groups 1 and 2 received 3000 IU of hCG (IM; Corulon�; Intervet International) and alpacas of groups 3 and 4 received 2.5 mL of GnRH (IM; Conceptal�; Intervet International) immediately after the first mating. Seven days after the first mating, ovaries of all alpacas were examined by transvaginal ultrasonography. Ovarian response was estimated by determining the number of CL present on each ovary. The numbers of follicles that were at least 8 mm in diameter were also counted. Data were analyzed as a complete randomized design with 4 treatments. The average number of CL per alpaca was 1.3, 1.00, 1.00, and 0.9 for groups 1 to 4, respectively (P > 0.05). The average number of follicles that were at least 8 mm in diameter per alpaca was 9.4, 20.4, 0.9, and 3.9 for groups 1 to 4, respectively (P ≤ 0.05) with females in group 2 showing the highest response. We conclude that progestin treatment did not affect ovulatory response of lactating alpacas to exogenous gonadotropins. An effective ovarian stimulation strategy for achieving superovulation in alpacas remains to be developed.
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