1,720,974 research outputs found
Studio per la semplificazione delle procedure dei controlli funzionali
No full textSono stati utilizzati 51645 dati di controlli mensili alternati effettuati durante 9790 lattazioni effettuate da capre Nere di Verzasca allevate sia in Italia che in Svizzera per verificare la possibilità di ridurre il numero di controlli. L’efficacia dei diversi metodi è stata valutata in termini di scarto sistematico e perdita precisione. La perdita di precisione utilizzando 3 controlli è risultata compresa tra 10 e 11% per il latte, tra 11 e 17% per il grasso e tra 13 e 26% per le proteine
Comparing Local and Commercial Breeds on Functional Traits and Profitability : the Case of Reggiana Dairy Cattle
No full textThe objective of this study was to compare fertility, longevity, milkability, and profitability of cows from the Reggiana and Holstein breeds in northern Italy. Profitability was gauged for each breed, with consideration of economic incentive programs and alternative milk pricing scenarios. Calving to first service interval, days open, and calving interval were significantly shorter in Reggiana than in Holstein cows. Reggiana cows conceived approximately one estrus cycle before Holstein and had a calving interval 33 d shorter. Holstein cows released a significantly higher quantity of milk per unit of time (1.81 vs. 1.28 kg/min). Reggiana cows had longer expected total and productive lives than Holstein cows, by 5.8 and 10.0 mo, respectively. Replacement rate was 26% higher in the Holstein. Standard 305-d milk production was 5,360 and 7,870 kg in Reggiana and Holstein, respectively. Comparing breeds on annual milk and meat production, instead of standard 305-d milk yield, changed marginally the difference in annual profitability between the Reggiana and Holstein, from -€696 to -€679 per cow per year. Including feeding, milking, replacement, and insemination costs reduced the gap between breeds by 32%, from -€679, measured on annual milk and meat production, to -€460. These differences in profitability assumed a pricing scenario referring to milk sold to the dairy industry where protein and fat contents are valued but not the breed origin of milk. Incentive payments to farmers of endangered cattle compensated partially (22%) the lower income from Reggiana cows. When Reggiana milk production was sold as branded Parmigiano Reggiano cheese, Reggiana cows were more profitable than Holstein cows by €1,953 per cow per year
Going 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
Genetic parameters and selection for casein content in Italian Holstein and Brown Swiss
No full textA total of more than 2,000,000 records on casein contents were collected in Lombardia (Italy) during routine milk recording of Italian Holstein and Brown Swiss dairy cows. Variance components for casein were estimated as well as all the genetic correlations of casein with production and type traits considered in selection. According to the heritabilities estimated (12.4% for Brown and 9.36% for Holstein), breeding values were calculated for bulls and compared to the breeding values for total protein. The results of two different selection scenarios were compared for each breed when including protein or casein as selection criterion. Genetic progress expected for all traits selected were compared after 10 years of selection. The genetic variability of casein allows the use of this trait as selection criterion with the estimation of breeding values and its inclusion in selection indexes. Ranking of breeding values for casein and protein are very similar in both breeds. But some differences in genetic values for casein exist for the same level of breeding value for protein. Nevertheless results in genetic gain differ between breeds depending mainly on genetic correlations with the other traits selected. The positive results in selection response estimated for several traits suggest to the Brown Swiss Association the replacement of protein selection with casein. In contrast the smaller effects estimated for the Italian Holstein suggest to wait for more casein data collected before any change in selection program
Parametros geneticos de las caracteristicas morfologicas de ganado Carora
No full textSixteen (16) morphological traits from 3867 Carora cows in Venezuela were studied. Genetic parameters were analyzed using a multiple trait animal model. Fixed effects of herd- year of evaluation interaction, month evaluation, age, stage of lactation
classifier, within herd were considered, genetic parameters were obtained from REML estimates of covariance components.
The highest heritability was found for stature (0.47) and for body depth (0.27), whereas the lowest values were found for foot angle (0.03). Udder traits showed low heritability estimates ranging from 0.06 for rear with to 0.13 for de udder balance.
Higher estimations were found for tea placement side (0.16) and teat length (0.26). Genetic correlations among stature,
body depth, strength and rump width were high and ranged from 0.76 to 0.86. Fore udder attachment was positively associated with rear udder height (0.46), udder depth
(0.53), teat placement (0.17) and length (0.18) while a negative correlations with udder balance (-.028). Negative estimates genetic correlations were found between rump angle (-0.45), rear-legs rear view (-0.50), udder balance (-0.68), udder support
(-0.32) y la angularity. Angularity was positively associated with rear udder height 0.62. Small correlations were estimated between foot angle and most traits. Negative genetic correlations
between body development and udder traits suggested that selection to increase body size could not improve the udder conformation. Selection should be oriented towards animals
of medium size dairy characteristics
Carora cattle shows high variability at αSl-casein
No full textThe objective of this study was to analyze the genetic variability of milk proteins of the Carora, a short-horned Bos taurus cattle breed in Venezuela and in other Southern American countries that is primarily used for milk production. A total of 184 individual milk samples were collected from Carora cattle in 5 herds in Venezuela. The milk protein genes αs1-casein (CN) (CSN1S1), β-CN (CSN2), κ-CN (CSN3), and β-lactoglobulin (LGB) were typed at the protein level by isoelectrofocusing. It was necessary to further analyze CSNlSl at the DNA level by a PCR-based method to distinguish CSN1S1*G from B. Increased variation was found in particular at the CSN1S1 gene, where 4 variants were identified. The predominant variant was CSN1S1*B (frequency = 0.8). The second most common CSN1S1 variant was CSN1S1*G (0.101), followed by CSN1S1*C (0.082). Moreover, a new isoelectrofocusing pattern was identified, which may result from a novel CSN1S1 variant, named CSN1S1*I, migrating at an intermediate position between CSN1S1*B and CSN1S1*C. Six cows carried the variant at the heterozygous condition. For the other loci, predominance of CSN2*A 2 (0.764), CSN3*B (0.609), and LGB*B (0.592) was observed. Haplotype frequencies (AF) at the CSN1S1-CSN2-CSN3 complex were also estimated by taking association into account. Only 7 haplotypes showed AF values >0.05, accounting for a cumulative frequency of 0.944. The predominant haplotype was B-A2-B (frequency = 0.418), followed by B-A 2-A (0.213). The occurrence of the G variant is at a rather high frequency, which is of interest for selection within the Carora breed because of the negative association of this variant with the synthesis of the specific protein. From a cheese-making point of view, this variant is associated with improved milk-clotting parameters but is negatively associated with cheese ripening. Thus, milk protein typing should be routinely carried out in the breed, with particular emphasis on using a DNA test to detect the CSN1S*G variant. The CSN1S*G allele is likely to have descended from the Brown Swiss, which contributed to the Carora breed and also carries this allele
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Analisi del valore culturale delle razze caprine dell’arco alpino italiano
No full textMany livestock local breeds are still today custodian of local traditions. The aim of this work was to analyse the cultural value of ten goat breeds farmed on the Italian Alpine ark: Roccaverano, Valdostana,
Vallesana, Verzaschese, Lariana, Ciavenasca, Orobica, Bionda dell’Adamello, Mochena
and Passiria. The following aspects were considered: role in maintaining the traditional landscape, role in maintaining the traditional farming systems and the traditional tools for the management of
the animals and products making, role in maintaining gastronomy, role in maintaining folklore and handicrafts, presence in forms of artistic expression. The degree of endangerment of these cultural elements was assessed. The contribution of each breeds to the cultural variability of the metapopulation was computed. The parameters used were able to differentiate breeds on the basis of their cultural value. Many of these elements could be used to add economic value to the farming of these local breeds. In addition, the parameters used in this investigation could be used to define conservation priorities
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