1,720,978 research outputs found
ICS-PR: una nuova selezione per la Frisona Italiana
No full textCon l’uscita di Dicembre 2018 ANAFI pubblicherà il terzo indice di selezione nazionale della Frisona Italiana da affiancare al PFT e allo IES. Questo indice, sviluppato su specifica richiesta del Consorzio del Formaggio Parmigiano Reggiano, prenderà il nome di Indice Caseificazione e Sostenibilità – Parmigiano Reggiano (ICS-PR), e sarà finalizzato a massimizzare il reddito dell’allevatore in un contesto di produzione del latte destinato alla trasformazione casearia
Changes on female fertility aggregate index in Italian Holstein dairy cattle
No full textThe aggregate index for female fertility was introduced into the national Holstein cattle breeding objectives in 2005, and included five selection criteria, namely days from calving to first service (DTFS), non-return rate at 56 d from first insemination (NR56), calving interval (CI), angularity (ANG), and equivalent-mature milk yield (MY). Conception rate at first service (CR) was the only breeding goal. The objective of the present study was to revise this aggregate index by including new information from both linear scoring (body condition score, BCS), services and pregnancy testing (interval from first to last insemination, IFL). After edits, information was available on 5,466,546 primiparae calving since 1994; to reduce computational time, six subsets of approximately 15,000 cows were extracted. (Co)variance components of DTFS, NR56, IFL, MY, BCS, and CR were estimated simultaneously with a multi-trait animal model, which included the fixed effects of herd-year-season of calving (DTFS, NR56, IFL, MY, and CR), age-year of calving (DTFS, NR56, IFL, CR), month of calving (DTFS, IFL, CR), month of insemination (NR56), herd-year-season of linear scoring (BCS), age-stage of lactation at linear scoring (BCS), and year of calving (BCS). Random terms were animal additive genetic and the residual. At a national level, means of DTFS, NR56, IFL, BCS, MY, and CR were 88 d, 59%, 71 d, 2.98, 10,483 kg, and 35%, respectively. (Co)variances estimated in each subset were averaged to derive G and R matrixes. Heritability estimates of fertility traits ranged from 0.013 (NR56) to 0.076 (DTFS); heritability estimates of BCS and MY were 0.18 and 0.29, respectively. Selection index methodology was employed to derive appropriate index weights from (co)variances between breeding goal (CR) and (among) selection criteria. Results from the present study indicated that the genetic response of the breeding goal using information on BCS and IFL, substituting ANG and CI, respectively, increases by 5.6% after one selection round
Empirical economic values of production and functional traits in the Italian Holstein population
No full textGoing Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
A multicenter randomized open-label study to evaluate the effects of early Cyclosporine withdrawal versus reduction in de novo renal transplant patients receiving Sirolimus, Cyclosporine, Steroids and Basiliximab induction. Interim analysis at three months.
No full textRenal cysts and diabetes syndrome linked to mutations of the hepatocyte nuclear factor-1β gene: Description of a new family with associated liver involvement
No full textBackground: Mutations in the hepatocyte nuclear factor (HNF)-1beta gene (TCF2) are responsible for a syndrome characterized by maturity-onset diabetes of the young, a nondiabetic renal disease, genital malformations, and liver dysfunction. Methods: The HNF-1beta gene was screened for mutations in four members of an Italian family with early-onset, nonketotic diabetes or a familiar, nondiabetic renal disease and nonprogressive liver disorder. Results: The genetic analysis revealed an already described nonsense mutation in codon 177 of HNF-1beta gene (R177X) in the four related subjects. Clinical features included diabetes in three of four patients, monolateral renal hypoplasia with cysts in the controlateral kidney in two patients, and bilaterally small hyperechoic kidneys without cysts in the other two patients, Renal function Impairment was severe in one patient, requiring dialysis treatment, and mild in three. Three patients had nonprogressive liver dysfunction, with long-lasting enzyme alterations but no liver insufficiency or jaundice. Conclusion: HNF-1beta gene mutations are associated with a wide variability in severity and pattern of clinical symptoms within the same kindred regarding diabetes and renal impairment. Moderate liver dysfunction may be a so far overlooked component of the syndrome. (C) 2002 by the National Kidney Foundation, Inc
Factors associated with feed efficiency traits in Italian Jersey cows
No full textFeed efficiency in lactating cows is one of the major aspects in modern dairy farm management. Purpose of the present study was to identify sources of variation of body live weight (LW) and feed efficiency traits in a population of 8,516 primiparous Jersey cows. The variables tested included LW, fat corrected milk (FCM), predicted dry matter intake (pDMI), energy corrected milk (ECM), and predicted feed efficiency (pFE_ECM), defined as ECM/pDMI. Linear scoring and age at evaluation were used to estimate LW. Factors associated with such traits were investigated using linear mixed models which included the fixed effects of origin of the paternal grandsire (USA, Denmark, Canada), stage of lactation, year of birth, and age at first calving. Random terms were cow, contemporary group (herd-year-season at linear scoring), and the residual. Mean of LW and pFE_ECM were 435 kg and 1.36, respectively. Feed efficiency was weakly negatively correlated (-0.15) with LW, and pDMI was positive correlated with ECM (0.88). Values of LW ranged from 444.01 to 449.88 kg in cows born between 2006 and 2014. Furthermore, cows with paternal grandsire born in Canada were the heaviest, but they had the lowest values for FCM, pDMI, ECM and pFE_ECM. Feed efficiency, FCM, ECM, and pDMI increased in the first three months of lactation, and then decreased. Kilos of pDMI and FCM increased concurrently with age at first calving and systematically decreased as year of birth proceeds. Energy corrected milk of cows born between 2011 and 2014 was lower than ECM of animals born between 2008 and 2010, consequently resulting in lower pFE_ECM. Late calving Jerseys were less feed efficient compared to early calving contemporaries. Systematic environmental factors associated with feed efficiency will be used to adjust phenotypes for routine genetic evaluation
Alternative Use of Somatic Cells Counts in Genetic Selection for Mastitis Resistance: A new Estimated Breeding Value for Italian Holstein Breed
No full textA new breeding value estimation for mastitis resistance has been implemented in the Italian Holstein dairy genetic evaluation. This breeding value uses indicators derived from test-day somatic cell counts (SCC) in order to predict the breeding value for resistance to mastitis occurrence. The pattern of test-day SCC contains additional information on mastitis resistance beyond its mean value usually used. These breeding values are combined in an “udder health” index, using different weights based on (co)-variance structure among indicators and direct mastitis observations. This new index will be additional to the already used somatic cell score index. The correlation between the two indexes is estimated at 80% meaning that the two are in the same direction, but they differ in terms of ranking individuals. In order to set up the new index, several indicators, derived from test-day somatic cell counts, have been derived. Alternative SCC traits were: mean and standard deviation of somatic cell score within lactation (SCSt and SD_SCSt, respectively), between 5 and 150 DIM (SCS150 and SD_SCS150, respectively), and between 151 and 305 DIM (SCS305 and SD_SCS305, respectively); infection, a dichotomous trait indicating that at least one SCC test-day record was above 100,000 cells mL-1 within lactation; severity, the ratio between the number of test-days with SCC greater than 100,000 cells mL-1 and the total number of test-days; severity, the ratio between the number of test-days with SCC greater than 400,000 cells mL-1 and the total number of test-days; and cell’s peak defined as the number of peaks during lactation (number of times when SCC shows a change from <100,000 to >400,000 mL-1 on three consecutive test-days). Once indicators traits have been defined, these have been validated on a sample data-set with direct mastitis information. Multiple trait animal model has been applied and genetic parameter for these traits including direct mastitis have been estimated. The highest genetic correlations between mastitis itself and indicators were with SCS150, SD_SCS, severity and peak equal to 0.39, 0.44, 0.41 and 0.51 respectively. Selection index methodology was applied to estimate appropriate weights to combined these four traits in the aggregate udder health index. This index has been published for the first time during December 2017 evaluation with mean 100 and standard deviation 5. Initially this index will be published only for national and international bulls. Following steps are to set up the genomic evaluation and, also, to participate to the GMace evaluation
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