Microbial Community in the Forestomachs of Alpacas (Lama pacos) and Sheep (Ovis aries)

Four 2-yr old alpacas （（48±2.3） kg） and four 2-yr old sheep （（50±1.7） kg） were used to study the pH and microbial community of forestomach from alpacas （Lama pacos） and sheep （Ovis aries） fed fresh alfalfa as the sole forage at low altitude （793 m）. The forestomach fluid was taken anaerobically via the esophagus. The electric pH meter and quantitative polymerase chain reaction systems were used to study the the pH and microbial community of forestomach. The results showed that the mean pH of forestomach fluid from alpacas was higher than that from sheep （P〈0.01）. The percentages of methanogens and Ruminococcusflavefaciens to total bacterial were lower in the forestomach of alpacas than that in the rumen of sheep, while the percentage of fungi and Fibrobacter succinogenes were higher. The percentage of protozoa was similar in the forestomach of alpacas and sheep. These differences can partly explain the reason that alpacas were lower methane production than sheep.

Molecular Identification of Shiga-Toxin Producing and Enteropathogenic <i>Escherichia coli</i>(STEC and EPEC) in Diarrheic and Healthy Young Alpacas

Isolation and biochemical and molecular identification of 303 strains of Escherichia coli obtained from diarrheic and healthy young alpacas of Puno-Peru, were realized. PCR amplification for 7 virulence factor genes associated with STEC, STEC O157:H7, EPEC: sxt1, sxt2, rfbO157, fliCH7, hlyA, eae y bfp were determined. A total of 39 strains (12.88%) showed amplification for one or more of these genes. Twenty three strains (59%) were classified as STEC and 16 strains (41%) as EPEC. An 88.18% (34/39) of STEC and EPEC strains were obtained from healthy alpacas and only 11.82% (5/39) from diarrheic alpacas considering this specie as potential zoonotic reservoir of STEC and EPEC.

Cloning and Expression Level Analysis of Melanocyte-stimulating Hormone Receptor 1 Gene(MC1R) in Alpacas with Different Coat Color

Specific primers for the MC1R gene of alpacas(GenBank EU1358800) were designed to amplify the cDNA sequence using RT-PCR to seek variation in the sequence and explore the relationship between the expression level of MC1R gene and alpaca coat color.The MC1R gene from white alpaca was cloned successfully and sequence analysis verified that the MC1R gene,encoding 317 amino acids,was 1081 bp in length.Compared with the existing sequence in GenBank,sequence identity was 99.9%and 7 mutations were found.Primers,designed from the sequence obtained,were used to assess the relative expression of MC1R in alpacas of different coat color using QRT-PCR and SPSS 13.0 software.Relative expression of MC1R in the skin of brown alpacas was 4.32 times higher than that in white alpacas after normalization with GAPDH(P【0.01),indicating that MC1R expression may be related to coat color of alpacas.

Effects on the quality of frozen-thawed alpaca(Lama pacos)semen using two different cryoprotectants and extenders

Aim： To evaluate two extenders and two cryoprotectant agents （CPA） for alpaca semen cryopreservation. Methods： Semen samples were obtained from four adult alpacas （Lama pacos） and frozen using extender Ⅰ （TRIS, citrate, egg yolk and glucose） or extender Ⅱ （skim milk, egg yolk and fructose）, each containing either glycerol （G） or ethylene glycol （EG） as CPA. Consequently, four groups were formed： 1） extender Ⅰ-G; 2） extender Ⅰ-EG; 3） extender Ⅱ-G; and 4） extender Ⅱ-EG. Semen was diluted in a two-step process： for cooling to 5 ℃ （extenders without CPA）, and for freezing （extenders with CPA）. Viability and acrosome integrity were assessed using trypan blue and Giemsa stains. Results： When compared, the motility after thawing was higher （P 〈 0.05） in groups Ⅱ-EG （20.0 %±6.7 %） and Ⅱ-G （15.3 %±4.1%） than that in groups Ⅰ-G （4.0 %±1.1%） and Ⅰ-EG （1.0 %±1.4 %）. Viable spermatozoa with intact acrosomes in groups Ⅱ-EG （18.7 %±2.9 %） and Ⅱ-G （12.7 %±5.9 %） were higher than that in groups Ⅰ-G （5.7 %±1.5 %） and Ⅰ-EG （4.0 %±1.0 %）. Conclusion： The skim milk- and egg yolk-based extenders containing ethylene glycol or glycerol to freeze alpaca semen seems to promote the survival of more sperm cells with intact acrosomes than the other extenders. （Asian J Androl 2005 Sep; 7： 303-309）

Ribosomal proteins expression and phylogeny in alpaca (<i>Lama pacos</i>) skin

Ribosomal proteins (RP) has been reported as a central player in the translation system, and are required for the growth and maintenance of all cell kinds. RP genes form a family of homologous proteins that express in the stable pattern and were used for phylogenetic analysis. Here we constructed a cDNA library of alpaca skin and 13,800 clones were sequenced. In the cDNA library, RP genes from skin cDNA library of alpaca were identified. Then 8 RP genes were selected at random and built the phylogenetic trees from the DNA sequences by using parsimony or maximum likelihood methods for molecular and evolutionary analysis of ribosomal proteins. The results showed that the 42 RP genes of alpaca have been expressed in alpaca skin. They were highly conserved. The phylogeny inferred from all these methods suggested that the evolutionary distances of alpaca RP genes were closer to rat.