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1.
J Anim Sci ; 90(10): 3385-91, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22585805

ABSTRACT

The aim of this study was to estimate direct and maternal genetic parameters for age at sale (AS, d), BW (kg), price (PR, €/kg), and market value (MV, €/calf) of Brown Swiss male calves (Bos taurus) from first- (n = 6,719) and second- (n = 4,405) parity dams marketed at livestock auctions from 2003 to 2007, and destined for veal production. Market value was calculated as the product of PR and BW. Restricted maximum likelihood procedures incorporating multiple trait animal models were used to infer genetic parameters for AS, BW, and PR, whereas estimates for MV were from single trait models. Bivariate analyses treating performance of calves from first- and second-parity cows as different traits were also performed. Direct heritabilities for AS, BW, and cattle prices ranged from 0.046 to 0.090, 0.078 to 0.130, and 0.064 to 0.152, respectively, and the corresponding maternal heritabilities varied from 0.020 to 0.030, 0.036 to 0.079, and 0.020 to 0.045, respectively. Direct genetic correlations between the traits were generally moderate to high and negative, whereas direct-maternal relationships were moderate to low. Genetic correlation between the same trait recorded on calves from first- and second-parity dams was less than unity, but generally high and positive, suggesting that AS, BW, PR, and MV can be treated as the same traits across parities. As calf price is routinely collected at auctions and shows genetic variation, it can be genetically improved.


Subject(s)
Animal Husbandry/economics , Body Weight , Breeding , Cattle/physiology , Heredity , Age Factors , Analysis of Variance , Animals , Cattle/genetics , Female , Male , Models, Genetic
2.
J Anim Breed Genet ; 127(4): 300-7, 2010 Aug.
Article in English | MEDLINE | ID: mdl-20646117

ABSTRACT

The aim of the study was to assess crossbreeding effects for 305-day milk, fat, and protein yield and calving interval (CI) in Irish dairy cows (parities 1 to 5) calving in the spring from 2002 to 2006. Data included 188,927 records for production traits and 157,117 records for CI. The proportion of genes from North American Holstein Friesian (HO), Friesian (FR), Jersey (JE) and Montbéliarde (MO) breeds, and coefficients of expected heterosis for HOxFR, HOxJE and HOxMO crosses were calculated from the breed composition of cows' parents. The model used to assess crossbreeding effects accounted for contemporary group, age at calving within parity, linear regression on gene proportions for FR, JE and MO, and linear regression on coefficients of expected heterosis for HOxFR, HOxJE and HOxMO, as fixed effects, and additive genetic, permanent environmental and residual as random. Breed effects for production traits were in favour of HO, while for CI were in favour of breeds other than HO. The highest heterosis estimates for production were for HOxJE, with first-generation crosses yielding 477 kg more milk, 25.3 kg more fat, and 17.4 kg more protein than the average of the parental breeds. The highest estimate for CI was for HOxMO, with first-generation crosses showing 10.2 days less CI than the average of the parental breeds. Results from this study indicate breed differences and specific heterosis effects for milk yield traits and fertility exist in Irish dairy population.


Subject(s)
Cattle/genetics , Cattle/metabolism , Dairying , Hybridization, Genetic , Milk/metabolism , Reproduction , Seasons , Animals , Cattle/physiology , Hybrid Vigor , Time Factors
3.
J Dairy Sci ; 93(7): 3346-9, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20630250

ABSTRACT

The aim of the study was to quantify the effects of composite beta- and kappa-casein (CN) genotypes on genetic variation of milk coagulation properties (MCP); milk yield; fat, protein, and CN contents; somatic cell score; pH; and titratable acidity (TA) in 1,042 Italian Holstein-Friesian cows. Milk coagulation properties were defined as rennet coagulation time (RCT) and curd firmness (a(30)). Variance components were estimated using 2 animal models: model 1 included herd, days in milk, and parity as fixed effects and animal and residual as random effects, and model 2 was model 1 with the addition of composite beta- and kappa-CN genotype as a fixed effect. Genetic correlations between RCT and a(30) and between these traits and milk production traits were obtained with bivariate analyses, based on the same models. The inclusion of casein genotypes led to a decrease of 47, 68, 18, and 23% in the genetic variance for RCT, a(30), pH, and TA, respectively, and less than 6% for other traits. Heritability of RCT and a(30) decreased from 0.248 to 0.143 and from 0.123 to 0.043, respectively. A moderate reduction was found for pH and TA, whereas negligible changes were detected for other milk traits. Estimates of genetic correlations were comparable between the 2 models. Results show that composite beta- and kappa-CN genotypes are important for RCT and a(30) but cannot replace the recording of MCP themselves.


Subject(s)
Caseins/genetics , Cattle/genetics , Genetic Variation , Lactation/genetics , Milk/chemistry , Milk/metabolism , Animals , Caseins/analysis , Fats/analysis , Female , Genotype , Hydrogen-Ion Concentration , Linear Models , Milk/cytology , Milk Proteins/analysis
4.
Am J Med Genet A ; 149A(10): 2258-64, 2009 Oct.
Article in English | MEDLINE | ID: mdl-19764019

ABSTRACT

Mandibuloacral dysplasia type A (MADA) is characterized by growth retardation, postnatal onset of craniofacial anomalies with mandibular hypoplasia, progressive acral osteolysis, and skin changes including mottled pigmentation, skin atrophy, and lipodystrophy. Owing to its slowly progressive course, the syndrome has been recognized in adults, and pediatric case reports are scarce. We present the clinical case of two children in whom the diagnosis of MADA was made at an unusually early age. A 5-year-old boy presented with ocular proptosis, thin nose, and short and bulbous distal phalanges of fingers. A 4-year-old girl presented with round face and chubby cheeks, thin nose, bulbous fingertips, and type A lipodystrophy. In both, a skeletal survey showed wormian bones, thin clavicles, short distal phalanges of fingers and toes with acro-osteolysis. Both children were found to be homozygous for the recurrent missense mutation, c.1580G>A, (p.R527H) in exon 9 of the LMNA gene. Thus, the phenotype of MADA can be manifest in preschool age; diagnosis may be suggested by short and bulbous fingertips, facial features, and lipodystrophy, supported by the finding of acral osteolysis, and confirmed by mutation analysis.


Subject(s)
Bone Diseases, Developmental/congenital , Craniofacial Abnormalities/diagnosis , Mandibular Diseases/congenital , Age of Onset , Bone Diseases, Developmental/diagnosis , Bone Diseases, Developmental/epidemiology , Child, Preschool , Craniofacial Abnormalities/epidemiology , Female , Humans , Lipodystrophy/complications , Lipodystrophy/congenital , Lipodystrophy/diagnosis , Male , Mandibular Diseases/complications , Mandibular Diseases/diagnosis , Mandibular Diseases/epidemiology
5.
J Anim Sci ; 87(9): 3053-9, 2009 Sep.
Article in English | MEDLINE | ID: mdl-19542496

ABSTRACT

The aim of this study was to investigate the effect of different breeds and breed crosses on age (AC, d), BW (kg), price (PR, $/kg), and market value (MV, $/calf) of purebred and crossbred calves sold for veal and beef production. The Kovieh wholesale cattle organization (Bolzano, Italy) grouped calves from several dairy herds located in the Trentino-Südtirol region in Italy and sold them by public auctions. Data on AC, BW, PR, and MV from 96,458 calves were recorded from January 2003 to December 2007 and consisted of 4 pure breeds [2 dairy, Brown Swiss (BS) and Holstein-Friesian (HF); and 2 dual-purpose, Simmental (SI) and Alpine Grey (AG)], and 8 crossbreds by crosses of Limousin (LI) and Belgian Blue (BB) with the 4 dam breeds. Least squares means for AC, BW, PR, and MV were calculated for breeds and breed crosses with a model that included fixed effects of herd of birth, age (except for AC), sex, and breed of the calf, year and season of auction, and interactions between the main effects. The coefficients of determination of the models were 0.41, 0.51, 0.84, and 0.82 for AC, BW, PR, and MV, respectively. Sex, age, and breed were the most relevant sources of variation for BW (P < 0.001), whereas breed and sex were the most important sources of variation for AC, PR, and MV (P < 0.001). Also, PR and MV were significantly influenced (P < 0.01) by all the effects included in the model, except for season x age interaction in the case of MV. Market value of male was greater (P < 0.001) than that of female calves, with the exception of BS (-$28.76/calf) and HF (-$20.70/calf) purebred males. Dual-purpose purebred calves presented greater (P < 0.001) PR and MV than dairy purebreds (MV of $426.97/calf and $307.96/calf for SI and AG, and $256.24/calf and $275.65/calf for BS and HF, respectively). Calves from SI and AG dams had greater (P < 0.001) BW, PR, and MV than calves from BS and HF dams. Calves from SI cows had greater (P < 0.001) BW, PR, and MV than calves from AG cows. Crossbreeding with beef bulls increased (P < 0.001) BW, PR, and MV of calves from dairy and dual-purpose dams. Crossbreeding with BB bulls increased PR (+$2.58 +/- 0.04/kg; P < 0.001) and MV (+$190.84 +/- 3.62/calf; P < 0.001) of calves much more than LI. The use of beef bull semen on dairy herds resulted in an economic revenue from selling crossbred calves.


Subject(s)
Animal Husbandry/economics , Animal Husbandry/methods , Body Weight/physiology , Cattle/physiology , Commerce , Hybridization, Genetic , Age Factors , Analysis of Variance , Animals , Female , Least-Squares Analysis , Male , Pregnancy
6.
J Dairy Sci ; 92(1): 392-400, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19109297

ABSTRACT

The objective of this study was to estimate genetic parameters for conjugated linoleic acid (CLA) and other selected milk fatty acid (FA) content and for unsaturation ratios in the Italian Holstein Friesian population. Furthermore, the relationship of milk FA with milk fat and protein content was considered. One morning milk sample was collected from 990 Italian Holstein Friesian cows randomly sampled from 54 half-sib families, located in 34 commercial herds in the North-eastern part of Italy. Each sample was analyzed for milk percentages of fat and protein, and for single FA percentages (computed as FA weight as a proportion of total fat weight). Heritabilities were moderate for unsaturated FA, ranging from 0.14 for C16:1 to 0.19 for C14:1. Less than 10% of heritability was estimated for each saturated FA content. Heritability for index of desaturation, monounsaturated FA and CLA/trans-11 18:1 ratio were 0.15, 0.14, and 0.15, respectively. Standard errors of the heritability values ranged from 0.02 to 0.06. Genetic correlations were high and negative between C16:0 and C18:0, as well as between C14:0 and C18:0. Genetic correlations of index of desaturation were high and negative with C14:0 and C16:0 (-0.70 and -0.72, respectively), and close to zero (0.03) with C18:0. The genetic correlation of C16:0 with fat percentage was positive (0.74), implying that selection for fat percentage should result in a correlated increase of C16:0, whereas trans-11 C18:1 and cis-9, trans-11 C18:2 contents decreased with increasing fat percentage (-0.69 and -0.55, respectively). Genetic correlations of fat percentage with 14:1/14 and 16:1/16 ratios were positive, whereas genetic correlations of fat percentage with 18:1/18 and CLA/trans-11 18:1 ratios were negative. These results suggest that it is possible to change the milk FA composition by genetic selection, which offers opportunities to meet consumer demands regarding health aspects of milk and dairy products.


Subject(s)
Cattle/genetics , Fatty Acids, Unsaturated/genetics , Fatty Acids/genetics , Lactation/genetics , Linoleic Acids, Conjugated/genetics , Milk/chemistry , Animals , Fatty Acids/analysis , Fatty Acids, Unsaturated/analysis , Female , Least-Squares Analysis , Linoleic Acids, Conjugated/analysis , Male , Milk Proteins/analysis
7.
J Dairy Sci ; 92(1): 423-32, 2009 Jan.
Article in English | MEDLINE | ID: mdl-19109300

ABSTRACT

This study investigated the potential application of mid-infrared spectroscopy (MIR 4,000-900 cm(-1)) for the determination of milk coagulation properties (MCP), titratable acidity (TA), and pH in Brown Swiss milk samples (n = 1,064). Because MCP directly influence the efficiency of the cheese-making process, there is strong industrial interest in developing a rapid method for their assessment. Currently, the determination of MCP involves time-consuming laboratory-based measurements, and it is not feasible to carry out these measurements on the large numbers of milk samples associated with milk recording programs. Mid-infrared spectroscopy is an objective and nondestructive technique providing rapid real-time analysis of food compositional and quality parameters. Analysis of milk rennet coagulation time (RCT, min), curd firmness (a(30), mm), TA (SH degrees/50 mL; SH degrees = Soxhlet-Henkel degree), and pH was carried out, and MIR data were recorded over the spectral range of 4,000 to 900 cm(-1). Models were developed by partial least squares regression using untreated and pretreated spectra. The MCP, TA, and pH prediction models were improved by using the combined spectral ranges of 1,600 to 900 cm(-1), 3,040 to 1,700 cm(-1), and 4,000 to 3,470 cm(-1). The root mean square errors of cross-validation for the developed models were 2.36 min (RCT, range 24.9 min), 6.86 mm (a(30), range 58 mm), 0.25 SH degrees/50 mL (TA, range 3.58 SH degrees/50 mL), and 0.07 (pH, range 1.15). The most successfully predicted attributes were TA, RCT, and pH. The model for the prediction of TA provided approximate prediction (R(2) = 0.66), whereas the predictive models developed for RCT and pH could discriminate between high and low values (R(2) = 0.59 to 0.62). It was concluded that, although the models require further development to improve their accuracy before their application in industry, MIR spectroscopy has potential application for the assessment of RCT, TA, and pH during routine milk analysis in the dairy industry. The implementation of such models could be a means of improving MCP through phenotypic-based selection programs and to amend milk payment systems to incorporate MCP into their payment criteria.


Subject(s)
Milk/chemistry , Spectrophotometry, Infrared/methods , Animals , Cattle , Chymosin/metabolism , Hydrogen-Ion Concentration , Linear Models
8.
J Dairy Sci ; 91(10): 4022-7, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18832228

ABSTRACT

The aim of the study was to estimate the effect of the composite CSN2 and CSN3 genotypes on milk coagulation, quality, and yield traits in Italian Holstein cows. A total of 1,042 multiparous Holstein cows reared on 34 commercial dairy herds were sampled once, concurrently with monthly herd milk recording. The data included the following traits: milk coagulation time; curd firmness; pH and titratable acidity; fat, protein, and casein contents; somatic cell score; and daily milk, fat, and protein yields. A single-trait animal model was assumed with fixed effects of herd, days in milk, parity, composite casein genotype of CSN2 and CSN3 (CSN2-CSN3), and random additive genetic effect of an animal. The composite genotype of CSN2-CSN3 showed a strong effect on both milk coagulation traits and milk and protein yields, but not on fat and protein contents and other milk quality traits. For coagulation time, the best CSN2-CSN3 genotypes were those with at least one B allele in both the CSN2 and CSN3 loci. The CSN3 locus was associated more strongly with milk coagulation traits, whereas the CSN2 locus was associated more with milk and protein yields. However, because of the tight linkage between the 2 loci, the composite genotypes, or haplotypes, are more appropriate than the single-locus genotypes if they were considered for use in selection.


Subject(s)
Caseins/genetics , Cattle/genetics , Lactation/genetics , Milk/chemistry , Milk/standards , Animals , Female , Genotype , Italy , Milk/metabolism , Milk Proteins/analysis
9.
J Dairy Sci ; 91(10): 4092-102, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18832237

ABSTRACT

In Italy, more than 75% of milk is used for cheese making. For this reason, milk composition and coagulation traits and cheese quality represent the most important tools for the economic development of the dairy sector. In particular, cheese quality varies in relation to cheese-making technology and breed of cow. The aim of this study was to investigate the effect of 3 types of milk, originating from Holstein-Friesian (HF), Brown Swiss (BS), and mixed of both breeds, on vat milk characteristics, cheese yield, and quality in 3 different typical Italian cheese-making conditions (Casolet, Vezzena, and Grana Trentino). One hundred forty-four cows (66 HF and 78 BS) were involved, and a total of 24 vats of milk were evaluated. At maturity, 30, 21, and 16 wheels of Casolet, Vezzena, and Grana Trentino cheese were analyzed. Brown Swiss cows yielded 9% less milk per day than HF cows, but milk showed greater contents of protein, casein, titratable acidity, and better rennet coagulation time and curd firmness than HF milk. The chemical composition and cholesterol content of the 3 types of cheese were similar between breeds, whereas the cheese made with BS milk showed greater contents of monounsaturated and polyunsaturated fatty acids. Cheese made with BS milk had greater b* (yellow component) than HF. Cheese yield, recorded at different ripening times, demonstrated that BS milk yielded more cheese than HF. Mixed milk showed values, on average, intermediate to HF and BS milk characteristics, and this trend was confirmed in cheese yield at different ripening times.


Subject(s)
Cheese/standards , Milk/chemistry , Milk/standards , Animals , Breeding , Cheese/analysis , Food Technology , Least-Squares Analysis
10.
J Dairy Sci ; 91(10): 4103-12, 2008 Oct.
Article in English | MEDLINE | ID: mdl-18832238

ABSTRACT

The objectives of the study were to estimate the reproducibility and repeatability of milk coagulation properties (MCP) measured by a computerized renneting meter (CRM) and to evaluate the predictive ability of mid-infrared spectroscopy (MIRS) as an innovative technology for the assessment of rennet coagulation time (RCT, min) and curd firmness (a(30), mm). Four samples without addition of preservative (NP) and 4 samples with Bronopol addition (PS) were collected from each of 83 Holstein-Friesian cows. Six hours after collection, 2 replicated measures of MCP were obtained with CRM using 1 NP and 1 PS sample from each cow. Mid-infrared spectra of the remaining NP and PS samples from each animal were recorded after 6 h, 4 d, and 8 d after sampling. Two groups of calibration equations were developed using MIRS spectra and CRM measures of MCP as reference data obtained from analysis of NP and PS, respectively. Reproducibility and repeatability of CRM measures were obtained from REML estimation of variance components on the basis of a linear model including the fixed effects of herd and days in milk class and the random effects of cows, sample treatment (addition or no addition of preservative), and the interaction between cow and sample treatment. Coefficient of reproducibility is an indicator of the agreement between 2 measurements of MCP for the same milk sample preserved with or without addition of Bronopol. Coefficient of repeatability is an indicator of the agreement between repeated measures of MCP. Pearson correlations between MCP measures for NP and PS were 0.97 and 0.83 for RCT and a(30), respectively. Reproducibility of CRM measures under different preserving conditions of milk was 93.5% for RCT and 64.6% for a(30). Repeatabilities of RCT and a(30) measures were 95.7 and 77.3%, respectively. Based on the estimated cross-validation standard errors and coefficients of determination and ratios of standard errors of cross-validation to standard deviation of reference data, the predictive ability of MIRS calibration equations was moderate for RCT and unsatisfactory for a(30.) Predictive ability of equations based on spectra and MCP measures of PS was greater than that of equations based on data of NP. The study did not provide conclusive evidence on the effectiveness of MIRS as a predictive tool for MCP and it requires an enlargement of the variability of milk sampling circumstances. Because the relevance of MIRS predictions in relation to breeding programs for MCP based on indicator traits relies on the genetic variation of MIRS predictions and on phenotypic and genetic correlations between MIRS predictions and MCP measures, additional specific investigations on these topics are needed.


Subject(s)
Food Technology/methods , Milk/chemistry , Spectrum Analysis/methods , Animals , Chymosin/chemistry , Food Handling , Reproducibility of Results , Spectrum Analysis/standards
11.
J Dairy Sci ; 91(8): 3184-9, 2008 Aug.
Article in English | MEDLINE | ID: mdl-18650296

ABSTRACT

Associations between stearoyl-CoA desaturase (SCD) gene polymorphisms and milk production traits (milk, fat, and protein yields, fat and protein contents, somatic cell score) were investigated on a sample of 701 lactations of 313 Italian Holsteins. Test-day records (5,097) were analyzed with a mixed linear model that included the fixed effects of herd, date of test, parity, genotype at the SCD locus, and lactation interval nested within SCD genotype, and the random effect of cow. An effect of the SCD genotype on milk and protein yields was detected, with VV cows producing more milk (about 2 kg/d) and protein (about 0.07 kg/d) compared with AA cows. The contribution of the SCD locus to the phenotypic variance of the 2 traits was about 0.015. These results suggest a possible use of the SCD locus in gene-assisted selection programs for the improvement of milk production traits in dairy cattle, although large-scale studies in different breeds are required.


Subject(s)
Breeding , Cattle/genetics , Lactation/genetics , Milk/metabolism , Polymorphism, Single Nucleotide , Stearoyl-CoA Desaturase/genetics , Amino Acid Substitution , Animals , Fats/analysis , Female , Genotype , Heredity , Italy , Least-Squares Analysis , Male , Milk/chemistry , Milk/cytology , Milk Proteins/analysis , Phenotype
12.
J Anim Breed Genet ; 125(2): 137-44, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18363979

ABSTRACT

The present study was a contribution on the genetic characterization of the Burlina local cattle breed, and an approach to understanding the relationships between Burlina, Holstein Friesian and Brown Swiss which represent the majority of the dairy cattle reared nowadays in North-East Italy. The obtained results helped to clarify the genetic diversity and distinctiveness of Burlina population. In particular, the low genetic distance between Burlina and Holstein Friesian and the assignment of a moderate percentage of Burlina animals to Holstein Friesian suggested that crosses between them took place in the past, while crosses with Brown Swiss seemed to be less frequent. However, analyses of marker genotypes, showed a cluster with only Burlina individuals, which demonstrates the genetic distinctness of this breed. The Burlina breed showed the highest variability among the analysed breeds and its inbreeding coefficient was low. The data contribute to the feasibility of a conservation and selection programme for this breed and the results are useful for the implementation of a conservation strategy that should aim to conserve animals where the contribution from foreign breeds is as small as possible.


Subject(s)
Cattle/genetics , Alleles , Animals , Breeding , Cattle/classification , Female , Gene Frequency , Genetic Variation , Hybridization, Genetic , Italy , Male , Microsatellite Repeats , Species Specificity
13.
J Dairy Sci ; 91(1): 371-6, 2008 Jan.
Article in English | MEDLINE | ID: mdl-18096961

ABSTRACT

Milk coagulation properties (MCP) are an important aspect in assessing cheese-making ability. Several studies showed that favorable conditions of milk reactivity with rennet, curd formation rate, and curd strength, as well as curd syneresis, have a positive effect on the entire cheese-making process and subsequently on the ripening of cheese. Moreover, MCP were found to be heritable, but little scientific literature is available about their genetic aspects. The aims of this study were to estimate heritability of MCP and genetic correlations among MCP and milk production and quality traits. A total of 1,071 Italian Holstein cows (progeny of 54 sires) reared in 34 herds in Northern Italy were sampled from January to July 2004. Individual milk samples were collected during the morning milking and analyzed for coagulation time (RCT), curd firmness (a30), pH, titratable acidity, fat, protein, and casein contents, and somatic cell count. About 10% of individual milk samples did not coagulate in 31 min, so they were removed from the analyses. Estimates of heritability for RCT and a30 were 0.25 +/- 0.04 and 0.15 +/- 0.03, respectively. Estimates of genetic correlations between MCP traits and milk production traits were negligible except for a30 with protein and casein contents (0.44 +/- 0.10 and 0.53 +/- 0.09, respectively). Estimates of genetic correlations between MCP traits and somatic cell score were strong and favorable, as well as those between MCP and pH and titratable acidity. Selecting for high casein content, milk acidity, and low somatic cell count might be an indirect way to improve MCP without reducing milk yield and quality traits.


Subject(s)
Cattle/genetics , Cheese , Milk/chemistry , Animals , Female , Italy , Lactation , Linear Models , Male , Milk/metabolism , Selection, Genetic
14.
Meat Sci ; 80(2): 389-95, 2008 Oct.
Article in English | MEDLINE | ID: mdl-22063344

ABSTRACT

The assessment of a method able to assign individuals to the breed of origin is needed to certify origin and quality of livestock products. A set of 21 microsatellites was tested for breed identification in four native Italian beef breeds: Chianina, Marchigiana, Romagnola, and Piemontese. Two statistical approaches, based on maximum likelihood and on a Bayesian method, were evaluated. Different marker sets, chosen in order of the highest gene diversity and F(ST) estimates were also tested. The Bayesian method performed better, achieving a correct assignment rate of about 90% even with six microsatellites. The marker sets with the highest gene diversity were shown to perform best. Considering a threshold probability of 90%, only 52.5% of the genotypes were correctly allocated. Such results are mainly due to the low genetic differentiation estimates among breeds (F(ST)=0.049). These findings suggest that markers with high gene diversity and the presence of private alleles should be investigated and the Bayesian method used.

15.
J Dairy Sci ; 90(12): 5737-43, 2007 Dec.
Article in English | MEDLINE | ID: mdl-18024767

ABSTRACT

This study aimed to estimate genetic parameters for body condition score (BCS), calving interval (CI), somatic cell score (SCS), yield, and linear type traits for the Italian Brown Swiss cattle population. A total of 32,359 records of first-parity lactating cows were collected from 2002 to 2004 in 4,885 dairy herds. The pedigree file included 96,661 animals. Multiple-trait animal models were analyzed using REML to estimate (co)variance components without repeated observations on traits. The estimated heritability was 0.15 for BCS, 0.05 for CI, and 0.06 for SCS, and ranged from 0.09 to 0.14 for test-day yield traits and from 0.07 to 0.32 for linear type traits. The genetic correlations of CI with yield and most linear type traits were positive, whereas the correlation between CI and BCS was negative (-0.35). For type traits, BCS showed, in general, a moderately negative genetic correlation except for strength, pastern, and heel height. The genetic correlation of CI or BCS with SCS was moderately low but favorable (0.19 and -0.26, respectively). The estimated correlations indicated that selection for greater yield and type traits can exert unfavorable effects on the reproductive ability of cows. To counterbalance these effects and to carry out early prediction of breeding values of bulls for fertility, inclusion of BCS in the breeding program is advisable.


Subject(s)
Breeding , Cattle/genetics , Dairying/methods , Lactation/genetics , Reproduction/genetics , Animals , Body Composition/genetics , Body Constitution/genetics , Cell Count/veterinary , Female , Male , Milk/cytology , Milk/metabolism , Models, Genetic , Phenotype , Postpartum Period , Pregnancy , Quantitative Trait Loci/genetics
16.
J Dairy Sci ; 90(8): 3986-92, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17639010

ABSTRACT

Samples of herd milk (506) were analyzed to assess sources of variation for milk coagulation properties (MCP) for 5 different dairy cattle breeds. Data were recorded in 55 single-breed dairy herds in the Trento province, a mountain area in northeast Italy. The 5 cattle breeds were Holstein-Friesian (8 herds), Brown Swiss (16 herds), Simmental (10 herds), Rendena (13 herds), and Alpine Gray (8 herds). Herd milk samples were analyzed for the MCP traits, milk rennet coagulation time (RCT), curd-firming time, and curd firmness (a30), as well as protein and fat percentages, somatic cell count, Soxhlet-Henkel acidity, and bacterial count. An ANOVA was performed to study the effect of breed, herd within breed, DIM, month of lactation, protein and fat percentages, somatic cell score, titratable acidity, and log bacterial count within breed on MCP. Breed was the most important source of variation. In particular, the Rendena breed showed the best MCP traits at 13.5 min and 27.0 mm for RCT and a30, respectively. The Holstein-Friesian breed had the worst coagulation properties at 18.0 min and 17.5 mm for RCT and a30, respectively. The other 3 breeds showed intermediate coagulation properties. The RCT values were better at the beginning of lactation, whereas RCT and a30 values were better in September and October (14.3 min and 25.7 mm, respectively). Among the composition traits, only the titratable acidity affected MCP traits of herd milk positively.


Subject(s)
Breeding , Cattle/physiology , Milk/chemistry , Analysis of Variance , Animals , Cattle/classification , Chymosin/metabolism , Colony Count, Microbial , Dairying , Fats/analysis , Female , Hydrogen-Ion Concentration , Least-Squares Analysis , Milk/cytology , Milk Proteins/analysis , Time Factors
17.
J Dairy Sci ; 90(5): 2538-42, 2007 May.
Article in English | MEDLINE | ID: mdl-17430958

ABSTRACT

The study assessed the fertility and purity of sexed semen used for inseminating Holstein-Friesian heifers in commercial dairy herds. Sex-sorted semen from 4 proven Holstein-Friesian bulls and available under commercial conditions was used on nulliparous Holstein heifers reared on 61 dairy farms of northern Italy. Data from 536 artificial inseminations with pregnancy diagnosis and 258 calvings were analyzed using the logistic regression procedure. The effects of year and season of insemination or calving, age at insemination or calving, heifer inbreeding, and the sperm dose used for insemination on the probability of a positive pregnancy diagnosis or of the birth of a female calf, respectively, were studied. The overall pregnancy rate for sexed semen was 51% and was affected by year of insemination and bull. Heifers inseminated with sexed semen from 2 bulls had lower pregnancy rates than heifers inseminated with sexed semen from other bulls. Purity of the sexed sperm, based on the proportion of female calves, was 87% and this percentage was not affected by explanatory variables included in the logistic regression. The results demonstrate that bulls differ in terms of fertility of their sexed semen. Careful selection of the insemination sires used for sorted semen is advisable for avoiding low fertility inseminations.


Subject(s)
Cattle/physiology , Fertility/physiology , Semen/physiology , Sex Preselection/veterinary , Animals , Dairying/methods , Female , Insemination, Artificial/methods , Insemination, Artificial/veterinary , Male , Odds Ratio , Pregnancy , Pregnancy Rate , Sex Preselection/methods , Sex Ratio
18.
Genet Couns ; 17(4): 449-55, 2006.
Article in English | MEDLINE | ID: mdl-17375532

ABSTRACT

Anophthalmos with limb anomalies (Waardenburg Opththalmo-Acromelic Syndrome) is a very rare autosomal recessive multiple congenital anomaly syndrome, first described by Waardenburg et al. in 1961 (MIM 206920). It is characterized by mono or more often bilateral anophthalmia/microphthalmia and foot malformations, which can be observed in 91% of the patients. The most common anomaly of the feet is the presence of four toes. The hands are affected bilaterally in 77% of the cases. The most characteristic anomaly is the synostosis of the fourth and fifth metacarpals. To date, 33 cases from 19 families have been reported. We present an Italian case of anophthalmia with limb anomalies and a renal malformation, which has never been described in the literature.


Subject(s)
Anophthalmos/complications , Kidney/abnormalities , Limb Deformities, Congenital/complications , Consanguinity , Ethnicity , Humans , Infant , Italy , Male , Syndactyly/complications , Waardenburg Syndrome/diagnosis
19.
J Dairy Sci ; 84(10): 2321-6, 2001 Oct.
Article in English | MEDLINE | ID: mdl-11699465

ABSTRACT

This study aimed to estimate heritability for condition score and heart girth using a test-day model, to investigate the genetic relationships between condition score, heart girth, and milk yield traits and to analyze the genetic relationships of condition score and heart girth measured at different stages of lactation. Cows from 25 dairy herds were scored for body condition and measured for heart girth at 3-mo intervals for 2 yr. Approximately 5000 test-day observations on condition score, heart girth, and milk fat and protein yield from 1344 Italian Friesian cows were analyzed using two approaches: 1) repeated observations for a trait were considered repeated measurements of the same trait; 2) observations for a trait collected in different stages of lactation (dry period, 1 to 75, 76 to 130, 131 to 210, and 211 to 300 DIM) were treated as different traits. (Co)variance components and related parameters were estimated using REML multiple-trait procedures and animal models with unequal design for different traits. Heritability estimates for fat and protein test-day yield and for test-day condition score and heart girth were 0.22, 0.18, 0.29, and 0.33, respectively. Condition score was negatively correlated with yield traits and positively correlated with heart girth, whereas genetic relationships between heart girth and milk yield traits were negligible. Heritability estimates were 0.27 for condition score recorded in the first half of lactation (1 to 75 and 76 to 130 DIM), 0.36 for condition score in the second half of lactation (131 to 210 and 211 to 300 DIM) and 0.32 for condition score recorded on dry cows. Genetic correlations between condition scores measured in different lactation stages were generally high (0.85 or more), with the exception of the relationships between the first and the last stage of lactation (0.74) and between the first half of lactation and the dry period (0.7). Heritability estimates for heart girth in different lactation stages ranged from 0.31 to 0.40, and genetic correlations between high girth measured in different lactation stages were higher than 0.80.


Subject(s)
Cattle/genetics , Heart/anatomy & histology , Lactation/genetics , Milk/metabolism , Animals , Body Weight , Cattle/anatomy & histology , Fats/analysis , Female , Lactation/physiology , Milk/chemistry , Milk Proteins/analysis
20.
J Anim Sci ; 78(10): 2532-9, 2000 Oct.
Article in English | MEDLINE | ID: mdl-11048917

ABSTRACT

Estimates of heritabilities and genetic correlations for calving ease over parities were obtained for the Italian Piedmontese population using animal models. Field data were calving records of 50,721 first- and 44,148 second-parity females and 142,869 records of 38,213 cows of second or later parity. Calving ability was scored in five categories and analyzed using either a univariate or a bivariate linear model, treating performance over parities as different traits. The bivariate model was used to investigate the genetic relationship between first- and second- or between first- and third-parity calving ability. All models included direct and maternal genetic effects, which were assumed to be mutually correlated. (Co)variance components were estimated using restricted maximum likelihood procedures. In the univariate analyses, the heritability for direct effects was .19 +/- .01, .10 +/- .01, and .08 +/- .004 for first, second, and second and later parities, respectively. The heritability for maternal effects was .09 +/- .01, .11 +/- .01, and .05 +/- .01, respectively. All genetic correlations between direct and maternal effects were negative, ranging from -.55 to -.43. Approximated standard errors of genetic correlations between direct and maternal effects ranged from .041 to .062. For multiparous cows, the fraction of total variance due to the permanent environment was greater than the maternal heritability. With bivariate models, direct heritability for first parity was smaller than the corresponding univariate estimate, ranging from .18 to .14. Maternal heritabilities were slightly higher than the corresponding univariate estimates. Genetic correlation between first and second parity was .998 +/- .00 for direct effects and .913 +/- .01 for maternal effects. When the bivariate model analyzed first- and third-parity calving ability, genetic correlation was .907 +/- .02 for direct effects and .979 +/- .01 for maternal effects. Residual correlations were low in all bivariate analyses, ranging from .13 for analysis of first and second parity to .07 for analysis of first and third parity. In conclusion, estimates of genetic correlations for calving ease in different parities obtained in this study were very high, but variance components and heritabilities were clearly heterogeneous over parities.


Subject(s)
Cattle/genetics , Labor, Obstetric/genetics , Parity/genetics , Animals , Cattle/classification , Female , Male , Models, Biological , Pregnancy
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