inheritance of suri and huacaya type of fleece in alpaca

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 (GT=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

Quantitative variation of melanins in alpaca (Lama pacos L.)

The amount of melanin pigments was investigated in 95 Peruvian alpaca, representative of six different fleece colours, by means of spectrophotometric assays: SpEM (Spectrophoto­metric Eumelanin), SpPM (Spectrophotometric Pheomelanin), SpASM (Spectrophotometric Alkali Soluble Melanin), and SpTM (Spectro­photometric Total Melanin). It was found that these melanin pigments were suitable for identifying three homogeneous groups, each consisting of two closely related colours. A low, an intermediate, and a high amount of SpASM, SpTM, and SpPM characterize pinkish grey and light reddish brown, brown and reddish brown, dark reddish brown and black fleeces, respectively. SpEM and SpTM provide a further split within this latter group; higher concentrations of these pigments distinguish black fleece from dark reddish brown

Variability of fibre quality on Chinese Alashan Left Banner White Cashmere goat

The heritability and the phenotypic and genetic correlations of down weight (DW), down fibre diameter (DFD), and coefficient of variation of the down fibre diameter (CVDFD) of Chinese Alashan Left Banner White Cashmere goat were estimated on 1375 one-year-old animals, born in 2009, 2011 and 2013 and bred at the Station for Livestock Improvement of Alashan (Left Banner, Inner Mongolia, P.R. China). For all traits, significant effects were for sex, cohort and sex–cohort interaction (p < .001). The heritability for DFD and CVDFD was high, 0.41 ± 0.08 and 0.52 ± 0.06, respectively. Heritability for the DW was low (0.12 ± 0.03). Phenotypic correlation calculated by Pearson's coefficient showed that DFD is positively correlated with both CVDFD (0.29 ± 0.07) and DW (0.20 ± 0.05). The phenotypic correlation between CVDFD and DW was negative (−0.11 ± 0.06). The genetic correlations between DW and CVDFD and between DFD and CVDFD were both high and positive (0.63 ± 0.16 and 0.39 ± 0.1, respectively) while the DW showed a negative genetic correlation with DFD (−0.27 ± 0.2). Our results suggest that the selection for reducing DFD and its CVDFD is possible and a genetic progress can be achieved quickly in the Chinese Alashan Left Banner White Cashmere goat

Efecto del doble corte en la calidad del vellón y en la actividad folicular en Alpacas (Llama pacos)

La presente investigación se realizó para analizar el efecto de una doble cizalladura sobre la calidad del vellón y sobre la actividad folicular de las alpacas (Llama pacos). Se han recogido biopsias de piel y muestras de fibra de 20 alpacas (10 hembras y 10 machos) divididas en dos grupos: el grupo A, sometido a doble esquila, uno a los 9 meses y el segundo, antes de la matanza, tiempo (16 meses de edad) y grupo B, sometidos tradicionalmente a una sola esquila a los 16 meses de edad. Todos los animales fueron analizados para: i) el diámetro promedio de la fibra total ii) el diámetro promedio de la fibra primaria (medulada), iii) el diámetro promedio de la fibra medulada continua, iv) el diámetro promedio de la fibra medulada fragmentada, v) el diámetro promedio de fibra no medulada (fibra secundaria), vi) el número de folículos primarios, vii) el número de folículos secundarios, viii) el porcentaje de folículos secundarios activos, y ix) la proporción de folículos secundarios a primarios. Tanto los animales de cizalla simple como los de cizalla doble no presentaron diferencias en la calidad de la fibra y en la estructura folicular. De forma diferente, el crecimiento de la fibra mostró una diferencia altamente significativa entre los dos grupos, ya que fue más lenta en el animal compartido. Se concluyó que los "alpaqueros" pueden maximizar la producción de vellón de su alpaca joven a través del método de la doble esquila. Palabras claves: Alpaca, Folículo, Fibra, Esquila

Fleece variation in alpaca (Vicugna pacos): a two-locus model for the Suri/Huacaya phenotype

Background: Genetic improvement of fibre-producing animal species has often induced transition from double coated to single coated fleece, accompanied by dramatic changes in skin follicles and hair composition, likely implying variation at multiple loci. Huacaya, the more common fleece phenotype in alpaca (Vicugna pacos), is characterized by a thick dense coat growing perpendicularly from the body, whereas the alternative rare and more prized single-coated Suri phenotype is distinguished by long silky fibre that grows parallel to the body and hangs in separate, distinctive pencil locks. A single-locus genetic model has been proposed for the Suri-Huacaya phenotype, where Huacaya is recessive. Results: Two reciprocal experimental test-crosses (Suri x Huacaya) were carried out, involving a total of 17 unrelated males and 149 unrelated females. An additional dataset of 587 offspring of Suri x Suri crosses was analyzed. Segregation ratios, population genotype frequencies, and/or recombination fraction under different genetic models were estimated by maximum likelihood. The single locus model for the Suri/Huacaya phenotype was rejected. In addition, we present two unexpected observations: 1) a large proportion (about 3/4) of the Suri animals are segregating (with at least one Huacaya offspring), even in breeding conditions where the Huacaya trait would have been almost eliminated; 2) a model with two different values of the segregation ratio fit the data significantly better than a model with a single parameter. Conclusions: The data support a genetic model in which two linked loci must simultaneously be homozygous for recessive alleles in order to produce the Huacaya phenotype. The estimated recombination rate between these loci was 0.099 (95% C. L. = 0.029-0.204). Our genetic analysis may be useful for other species whose breeding system produces mainly half-sib families

Il Centro Allerta Tsunami (CAT) dell’INGV

The Tsunami Alert Centre of the INGV (CAT-INGV) was created with the aim of contributing to the mitigation of the risk due to tsunamis triggered by earthquakes on the Italian and Mediterranean coasts. Tsunamis of seismic origin, in addition to being the most frequent, are those that can be detected more quickly. Seismic waves, in fact, travel in the crust with a much higher speed than that of tsunami waves. With effective seismic networks connected in real time, an "Early Warning" system can be implemented, i.e. a system capable of sending an alert signal before the arrival of the tsunami waves, at least from a certain distance from the source. The CAT-INGV has two main tasks. The first one is to provide alerts to the competent authorities in the event of potential tsunamigenic earthquakes in the Mediterranean, taking into account the criteria defined by the Department of Civil Protection for this purpose. The second one consists in carrying out the necessary studies for the definition of the probabilistic danger of tsunamis for the Italian coasts, starting from those of seismic origin (Seismic Probabili-stic Tsunami Hazard Analysis, SPTHA). In this contribution the first aspect is described, while the realization of the studies on hazard at the Mediterranean scale is the subject of research described in various recent articles (Lorito et al., 2015; Grezio et al., 2017; Selva et al., 2017a; Selva et al., 2017b). The TSUMAPS-NEAM project, funded by the European Commission and concluded at the end of 2017, provided the first hazard map for the Mediterranean region and the north-east Atlantic (Basili et al., 2017).Published91-975T. Modelli di pericolosità sismica e da maremotoN/A or not JC