1,720,980 research outputs found
Dietary strategies aiming to reduce the environmental impact of ruminants
No full textRuminant livestock are responsible for non-CO2 greenhouse gas (GHG) emissions, namely methane from enteric fermentation and nitrous oxide, as indirect emissions from manure management. Reduction measures of GHG must be taken by all sectors to reach the European greenhouse gas production targets of 55% of net reduction by 2030 and of neutrality by 2050 (European green deal, Paris agreement). It has to be highlighted that livestock partly exploit resources, which are not in competition with humans, and enteric methane is a physiological need of ruminants; therefore, its production can be reduced but not eliminated. Despite this evidence, in the last decades, several feeding strategies have been proposed, which overall are pointing toward the improvement of animal efficiency and the reduction of their methane emission. Among these approaches, good practices in grazing management, forage harvesting and preservation strategies, together with the inclusion of concentrate of dietary fats, might help in mitigating the environmental impact of ruminants. Furthermore, several in vitro studies have reported the potential of including various feed additive types, either as pure or as a mixture, but confirmations in vivo are required
Ultrasonographic evaluation of the mammary cistern size during dry period in healthy dairy cows
Full text linkIntroduction
The dry period (DP) is defined as the nonlactating period prior to parturition in dairy cows. During the DP, new udder tissue
is formed and prepared for the next lactation [1]. The aim of this study was to evaluate the udder cistern (UC) size during the
dry period by the ultrasound technique.
Methods
Ten Italian Friesian cows were included, for a total of 40 quarters. All the cows underwent the same management condition.
The following inclusion criteria were set: 1) no heifer; 2) abruptly drying-off; 3) no mastitis or other diseases at drying-off
and during the whole study period. A convex probe (5 MHz) was placed immediately cranial to the insertion of each teat on
the udder in order to visualize the UC of each quarter. The probe was first held parallel to the teat for a longitudinal section,
then a 90° rotation was applied for the cross-section view [2]. All the animals were evaluated at the drying-off (T0) and
24 hours later (T1), then regularly until the end of the dry period (T7, T14, T21, T28, T38, T48, T58), during the colostrum
production phase (TCPP) and at 7 days in milking (T7PP). The Spearman test was applied to evaluate the correlation between
ultrasonographic UC size (UUCS) assessment and time. The Friedman test and the Dunn’s test for multiple comparisons
as post-hoc were performed to compare the cross-section UUCS of the forequarters (FQCS) and hindquarters (HQCS) and
the longitudinal section UUCS of the forequarters (FQL) and hindquarters (HQL) at T0 vs T58 vs TCPP vs T7PP. Values of
p <0.05 were considered statistically significant.
Results
No subject developed mastitis or other diseases during the study period. The ultrasound evaluation of the UUCS was easy to
perform in field conditions. A total of 440 images have been measured. There was a statistically significant negative linear
correlation between the time and the UUCS for FQCS and FQL (r = -0.95; p <0.0004) and for HQCS and HQL (r = -0.90; p
<0.002). The Friedman test was statistically significant (p <0.0001), showing that the UUCS at T58 were lower, compared
to other times for FQCS, FQL and HQCS. T0 did not differ from TCPP.
Conclusions
No studies can be found in literature evaluating the UUCS during the dry period. Studies on UC cellular proliferation showed
that the UC cellular involution during dry period peaked 25 days after the dry-off [3,4]. In our study, the UUCS decreased
throughout the whole dry period and started to increase at the beginning of the next lactation. This difference could be due
to a discrepancy between the UC cellular proliferative and the ultrasonographic evaluation of the UC. In conclusion, the
evaluation of the UUCS during the dry period in healthy cows was feasible for field conditions. UUCS might give useful
information for the udder dry period monitoring.
References
[1] Annen et al 2004. J Dairy Sci, 87: E66–76.
[2] Ayadi et al 2003. J Dairy Res, 70(1): 1-7.
[3] Capuco et al 2003. J Anim Sci 81, 18-31.
[4] Capuco et al 2006. Ruminant Physiology, 363-88
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
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
Detour test performance of cloned minipigs from three different clone populations
Full text linkGenetics, the uterine environment, maternal behavior, and rearing conditions can all influence animal behavioral phenotypes. Some studies on cloned pigs have found no differences between the behavioral patterns of cloned and non-cloned animals. Other studies conducted on dogs have reported similarities in the behavior of cloned subjects. This study evaluated the performance of 12 cloned minipigs from three different clone populations (A, B, C) in a detour test around symmetric and asymmetric barriers. We measured the detour time and patterns, in order to investigate the pigs' cognitive abilities.The detour time and the detour entry/exit pattern were recorded. All the animals tended to keep a fixed entry/exit pattern instead of modifying it to accommodate changes in the working set. Significant differences in detour time were found among the populations, with animals belonging to population B being faster than the others, and also within each population.Our study is one of the few to assess the cognitive abilities of cloned minipigs. The results indicate that even animals belonging to the same cloned population may develop different cognitive, hence behavioral characteristics. Whether cloning can be utilized to obtain similar behavioral phenotypes therefore remains a matter of debat
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
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