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Canaza-Cayo A.W.,Austral University of Chile | Alomar D.,Institute of Animal Production | Quispe E.,National University of Huancavelica
Animal | Year: 2013

Rapid and efficient methods to evaluate variables associated with fibre quality are essential in animal breeding programs and fibre trade. Near-infrared reflectance spectroscopy (NIRS) combined with multivariate analysis was evaluated to predict textile quality attributes of alpaca fibre. Raw samples of fibres taken from male and female Huacaya alpacas (n = 291) of different ages and colours were scanned and their visible-near-infrared (NIR; 400 to 2500 nm) reflectance spectra were collected and analysed. Reference analysis of the samples included mean fibre diameter (MFD), standard deviation of fibre diameter (SDFD), coefficient of variation of fibre diameter (CVFD), mean fibre curvature (MFC), standard deviation of fibre curvature (SDFC), comfort factor (CF), spinning fineness (SF) and staple length (SL). Patterns of spectral variation (loadings) were explored by principal component analysis (PCA), where the first four PC's explained 99.97% and the first PC alone 95.58% of spectral variability. Calibration models were developed by modified partial least squares regression, testing different mathematical treatments (derivative order, subtraction gap, smoothing segment) of the spectra, with or without applying spectral correction algorithms (standard normal variate and detrend). Equations were selected through one-out cross-validation according to the proportion of explained variance (R 2CV), root mean square error in cross-validation (RMSECV) and the residual predictive deviation (RPD), which relates the standard deviation of the reference data to RMSECV. The best calibration models were accomplished when using the NIR region (1100 to 2500 nm) for the prediction of MFD and SF, with R 2CV = 0.90 and 0.87; RMSECV = 1.01 and 1.08 μm and RPD = 3.13 and 2.73, respectively. Models for SDFD, CVFD, MFC, SDFC, CF and SL had lower predictive quality with R 2CV < 0.65 and RPD < 1.5. External validation performed for MFD and SF on 91 samples was slightly poorer than cross-validation, with R 2 of 0.86 and 0.82, and standard error of prediction of 1.21 and 1.33 μm, for MFD and SF, respectively. It is concluded that NIRS can be used as an effective technique to select alpacas according to some important textile quality traits such as MFD and SF. © 2013 The Animal Consortium. Source

Rivero M.J.,Institute of Animal Production | Lopez I.F.,Institute of Animal Production | Hodgkinson S.M.,Austral University of Chile
Journal of Animal Science | Year: 2013

The objective of this study was to evaluate the effect of herbage allowance on pasture DM consumption by growing European wild boar. An additional objective was to evaluate the influence of pasture consumption on supplemental diet intake and BW gain. A previously sown grass-clover pasture was managed by cutting to obtain an herbage mass equivalent to 1,500 kg/ha DM. Areas of pasture were limited by fencing to obtain 3 different herbage allowances whereas the pasture was removed in other areas. Forty-eight purebred European wild boars (initial age of 120 d and initial BW of 14.4 kg) were grouped in pairs and each pair was randomly allotted to 1 of 4 treatments (6 pairs per treatment): no pasture (4 m2; pasture removed), low (5.33 m2; 400 g/d pasture DM available/wild boar), medium (8 m2; 600 g/d pasture DM available/ wild boar), and high (16 m2; 1,200 g/d pasture DM available/wild boar). The treatment areas were moved daily with a 7-d rotation. For a 28-d period, wild boars entered their treatment areas from 0830 to 1630 h, after which they had free access to a supplemental diet for 1 h. Pasture consumption was estimated daily by cutting pasture samples pre- and postgrazing. Supplemental diet consumption was determined daily (feed offered minus remaining feed). Animals were weighed weekly. Pasture consumption differed (P < 0.001) among wild boars receiving different treatments, with cumulative consumptions of 3.0 and 3.9 kg DM/wild boar over 28 d for low and medium herbage allowances, respectively (P <0.09), and 6.4 kg DM/wild boar over 28 d for high herbage allowance, with the latter consumption being greater (P < 0.001) than the consumption recorded with the decreased herbage allowance treatments. The supplemental diet consumption tended (P = 0.16) to be less in wild boars with greater herbage allowance. European wild boars with access to pasture had greater (8.48 vs. 6.27 kg; P = 0.002) BW gain than those without access to pasture. In conclusion, pasture consumption by European wild boars can be enhanced by increasing herbage allowance and greater BW gains can be achieved in wild boars with access to pasture compared with those with no pasture access copyright © 2013 American Society of Animal Science. All rights reserved. Source

Vostry L.,Czech University of Life Sciences | Vostry L.,Institute of Animal Production | Mach K.,Czech University of Life Sciences | Pribyl J.,Institute of Animal Production
Archiv fur Tierzucht | Year: 2012

The objective of this paper was to select a suitable data subset and statistical model for the estimation of genetic parameters for 36 traits of the linear type in 977 Old Kladruber horses. Two subsets were tested to identify a suitable subset for analysis. One subset included repeated evaluation of certain individuals, whereas the other did not. The most suitable subset included repeated evaluation (n=1 390). The selection of a suitable model was made from 4 candidate models. These models comprised a number of random effects (direct individual effect and animal permanent environmental effect of the animal) and a number of fixed effects (colour variant, stud, colour variant × stud interaction, sex, age at description, year of birth, year of description). The model was selected based on the Akaike information criterion (AIC, Akaike 1974), residual variance and heritability coefficient. The model that included colour variant, stud, colour variant × stud interaction, sex, age at description, and year of description as fixed effects and direct individual and animal permanent environment as random effects was the most suitable model for the estimation of genetic parameters and for the subsequent estimation of breeding values. © Leibniz Institute for Farm Animal Biology, Dummerstorf, Germany. Source

Vostry L.,Czech University of Life Sciences | Vostry L.,Institute of Animal Production | Capkova Z.,Czech University of Life Sciences | Pribyl J.,Czech University of Life Sciences | And 2 more authors.
Czech Journal of Animal Science | Year: 2011

Genetic parameters, breeding values and inbreeding depression for 22 linear type description of conformation and type characters and 4 body measurements were evaluated in a group of 1744 horses of three original cold-blooded breeds in the Czech Republic in a long period of 18 years (1990-2007). Based on the values of Akaike's information criterion, residual variance and heritability coefficient, a model with fixed effects (sex, year of description, breed, and classifier) and with a random effect (animal) was selected. Heritability coefficients for the particular traits were in the range of 0.11 to 0.55 and genetic correlations ranged from -0.63 to 0.97. Inbreeding depression, expressed as coefficients of regression on one percent of inbreeding, was in the range of -0.0992 to 0.0242 points for the particular traits. The inclusion of inbreeding depression in the model resulted in a moderate change in h2 in one-third of the traits. In two-thirds of traits, the value of rG increased or decreased by 0.01. Standard deviations of the breeding values for linear type description of conformation and type characters were in the range of 0.30 to 0.72 and 0.62 to 6.18 for body measurement traits. Among breeding values estimated by a model without inbreeding depression and a model with inbreeding depression, Spearman's rank correlation coefficient values for the particular traits were 0.916-0.999 (sample of all horses), 0.710-0.992 (10% of the best horses) and 0.827-0.998 (10% of the worst horses). If the average value of the inbreeding coefficient is low (0.03), then it is not necessary to include the influence of inbreeding depression in the model for the genetic evaluation of individuals of original cold-blooded horses kept in the Czech Republic. Source

Vostry L.,Czech University of Life Sciences | Vostry L.,Institute of Animal Production | Capkova Z.,Czech University of Life Sciences | Pribyl J.,Czech University of Life Sciences | And 4 more authors.
Archiv fur Tierzucht | Year: 2011

In order to estimate effective population size, generation interval and the development of inbreeding coefficients (Fx) in three original breeds of cold-blooded horses kept in the Czech Republic: Silesian Noriker (SN), Noriker (N) and Czech-Moravian Belgian horse (CMB) all animals of the particular breeds born from 1990 to 2007 were analysed. The average values of generation interval between parents and their offspring were: 8.53 in SN, 8.88 in N and 8.56 in CMB. Average values of effective population size were estimated to be: 86.3 in SN, 162.3 in N and 104.4 in CMB. The average values of inbreeding coefficient were 3.13 % in SN stallions and 3.39 % in SN mares, in the N breed 1.76 % and 1.26 % and in the CMB breed 3.84 % and 3.26 % respectively. Overall averages of Fx were: 3.23 %, 1.51 % and 3.55 % for the breeds SN, N and CMB. The average value of inbreeding coefficient Fx increased by 1.22 % in SN, by 0.35 % in N and by 1.01 % in CMB, respectively. This may lead to a reduction in genetic variability. Reduction in genetic variability could be either controlled in cooperation with corresponding populations of cold-blooded breeds in other European countries or controlled by number of sires used in population. © Leibniz Institute for Farm Animal Biology, Dummerstorf, Germany. Source

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