1,721,071 research outputs found
THE ROLE OF SOME ADDITIVES IN ENHANCING FEED EFFICIENCY AND HEALTH IN MONOGASTRIC ANIMALS
Full text linkThe global demand for food from animal agriculture is anticipated to nearly double by 2050. The growth in white meat (pork and poultry) production in developing countries between 1989 and 1999 has been remarkable - more than double the growth of red meat (cattle, sheep and goats). Increased production can be achieved by a combination of expansion in animal numbers and increased productivity. Higher productivity is a compound of higher offtake rates (shorter production cycles by, for example, faster fattening), and higher carcass weight or milk or egg yields. The projections show that the increase in livestock numbers will remain significant, but less so than in the past. Higher carcass weights will play a more important role in beef production, while higher offtake rates (shorter production cycles) will be more important in pig and poultry meat production.
In order to increase health and feed efficiency in monogastric animals, four trials were carried out to evaluate the role of some additives used to increase health in post-weaning piglets and in poultry meat production.
The aim of first study was to evaluate the effects of nucleotides administration to post-weaning piglets on ileal proinflammatory interleukin gene expression. Thirty-six weanling piglets (28 d of age, 7.85 ± 0.25 kg L.W.) were used in 28 days study. Piglets were allotted to 2 homogeneous groups (C, T) and fed the basal diet supplemented with oral nucleotides (UMP 88.05%, GMP 5.51%, AMP 3.82%, CMP 1.94% and IMP 0.68%; 0.8 g/piglet/day in 2.1 ml water solution) or saline. On day 14 both experimental groups were challenged with 1x109 CFU/g E. coli 0149:F4(K88). Growth performance and faecal score were evaluated weekly, while blood samples for immunological serum parameters, Fe and Vitamin B12 serum content were collected on days 0, 13, 18 and 26. Proinflammatory IL1a, IL1b, IL6, IL10, and TNF, TLR2 and TLR4 gene expression in ileal Peyer patches were evaluated at slaughtering after individual tissue sample collection by RT-PCR and β-actin as housekeeping gene. Growth performances were not affected by dietary treatment, while faecal score was ameliorated in T piglets after one week on trial (P< 0.05). Haptoglobin serum content was decreased in treated pigs (P<0.01). Dietary treatment did not affect serum Fe content, while vitamin B12 level was higher in nucleotide-fed animals (P< 0.05). At slaughtering IL6, IL10, TNF, TLR2 and TLR4 gene expression were decreased in nucleotide-fed pigs (P< 0.01). By these findings, dietary nucleotides supplementation in post-weaning piglets can positively affect gut health status, ameliorating inflammatory response and digestibility of nutrients in microbial stress conditions.
Second study was carried out with the aim to investigate the antimicrobial potential of a polyphenol-rich olive extract in vitro and its effects on growth performance, caecum microbial population, slaughtering performance and meat quality. In vitro antimicrobial trials were performed on test cultures (E. coli ATCC 25922, L. monocytogenes ATCC 7644, S. Enteritidis ATCC 12592 and S. aureus ATCC 6833); the growth was assessed every 12 h for 48 h as optical density of broth cultures added with different concentrations of the product (0.1/0.5/1/5%) incubated at 20°C; an evident inhibition was observed with the increasing of the product concentration and a total inhibition was observed with the highest one. Considering these results, an in vivo trial was performed. A total of 720 female ROSS308 broiler chicks with day-old were allocated into 4 treatments with different dietary treatments (basal diet supplemented without (CTR) or with vitamin E (T1, 200 I.U. /kg for each dietary phase) or with Polyphenols olive extract (T2, 1g/kg and T3, 5 g/kg respectively in each dietary phase). Each group consisted of 9 pens with 20 birds per pen. Growth performances were determined at days 0, 10, 20 and 35. At day 35, two birds of each pen were chosen on average pen weight basis and slaughtered: from one was collected the cecum for microbial analyses and for the determination of the dressing and breast muscle percentages and the other one was collected for the measurements of pH, TBARS content and color at day 0 and after 9 days, mimicking the commercial preservation after slaughter.
Supplementation with polyphenols olive extract showed only a tendency in Feed Conversion Ratio, in particular in the three phase of administration and in overall performance period (0-35 d) of animals (respectively P=0.09 and P=0.07) and T2 result lower compared to control group. No other evidence was observed in growth performances measured included carcass measures on dressing and breast muscle percentage. In addition, no differences were observed in cecum microbial population and gut health indexes. TBARS showed a statistical tendency (P=0.075), T1 resulted with lower oxidation if compared to all other groups (P<0.05); pH value and color of breast, skin and thigh, expressed with L*, a* and b*, did not explain any statistically difference. In conclusion in addition to promising in vitro data obtained, it would be interesting to evaluate the potential of the administration of this type of polyphenols in animals subjected to the stress of intensive livestock production, where more interesting results due to potential expressed with antimicrobial and antioxidant activity could be obtained.
Third and fourth trials were carried out to evaluate different effects of a novel synthetic emulsifier.
First step, the third trial, consist in two experiments conducted to evaluate the effects of a novel synthetic emulsifier product (AVI-MUL TOP) on the growth performance of chickens for fattening and weaned piglets. The emulsifier product consists of 50% vegetal bi-distillated oleic acid emulsified with 50% glyceryl polyethyleneglycol ricinoleate. In Exp. 1, four hundred and eighty 1-d-old female Cobb500 chickens for fattening were assigned to two treatments: 1) a control diet (CTR); and 2) the control diet + the emulsifier (AMT, 1 g/kg from day 0 to day 10, 0.75 g/kg from day 10 to day 20 and 0.5 g/kg from day 20 to day 34). AMT supplementation increased body weight on days 20 and 34 (P < 0.01). Dietary AMT increased the average daily gain (ADG) and average daily feed intake (ADFI) from day 10 to day 20, from day 20 to day 34 and from day 0 to 34 (P < 0.01). A reduced feed conversion ratio was observed in the AMT group from day 10 to day 20 (P < 0.01). In Exp. 2, ninety-six Stambo HBI × Dalland piglets were weaned at 24 days and assigned to 2 treatments (the basal diet without the product (CTR) or with 2 g/kg emulsifier from day 0 to day 14 and 1.5 g/kg from day 14 to day 42 (AMT)). There was an increase in the ADFI associated with AMT supplementation from day 14 to day 42 (P = 0.04). These results indicated that supplementation with the synthetic emulsifier may significantly improve the growth performance of chickens for fattening and numerically improve that of weaned piglets.
Second step consist in to investigate the influence of a novel synthetic emulsifier product (AVI-MUL TOP) on growth performance, plasma lipid profile and hepatic expression of related genes in female and male broiler chicks. A total of 1200 ROSS308 broiler chicks with day-old were allocated into 4 treatments with a 2 × 2 factorial design comparing sex (female or male) and different dietary treatments (basal diet supplemented without (CTR) or with the emulsifier (AMT, 1 g/kg from d 0 to 12, 0.75 g/kg from d 12 to 22 and 0.5 g/kg from d 22 to 44, respectively)). Each group consisted of 15 pens, 20 birds per pen. Growth performance was determined at days 0, 12, 22 and 44 (37 for females). At day 44 (37 for females), one bird of each pen was chosen and slaughtered to collect blood and livers samples and determine the dressing and breast muscle percentages. Males had higher BW than female chicks on days 0 (P = 0.014), 12 (P < 0.01) and 22 (P < 0.01). Compared to females, male chicks had higher ADG and ADFI from day 0 to 12 and from day 12 to 22 (P < 0.01), and lower FCR from day 12 to 22 (P < 0.01). AMT supplementation increased the BW compared to the CTR group on days 12 (P = 0.02), and AMT chicks had higher ADG compared to the CTR birds from day 0 to 12 (P = 0.02). AMT male chicks had lower FCR compared to the CTR males from day 22 to 44 and day 0 to 44 (P = 0.047 and 0.02). However, there was no diet effect on growth performance of female chicks during the trial. AMT supplementation increased dressing percentage compared to the CTR group (P = 0.02). In addition, dietary AMT increased cholesterol, HDL and LDL contents compared to the CTR group (P < 0.01; P = 0.02; P < 0.01). In conclusion, supplementation of AMT may have beneficial effect on growth performance and plasma lipid profile of broiler chicks
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
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
The effects of a novel synthetic emulsifier product on growth performance of chickens for fattening and weaned piglets
Full text linkTwo experiments were conducted to evaluate the effects of a novel synthetic emulsifier product (AVI-MUL TOP) on the growth performance of chickens for fattening and weaned piglets. The emulsifier product consists of 50% vegetal bi-distillated oleic acid emulsified with 50% glyceryl polyethyleneglycol ricinoleate. In experiment 1, 480 1-day-old female Cobb500 chickens for fattening were assigned to two treatments: (1) a control diet (CTR); and (2) the control diet+the emulsifier (AMT, 1 g/kg from day 0 to day 10, 0.75 g/kg from day 10 to day 20 and 0.5 g/kg from day 20 to day 34 of the trial). AMT supplementation increased BW on days 20 and 34 (P<0.01). Dietary AMT increased the average daily gain and average daily feed intake (ADFI) from day 10 to day 20, from day 20 to day 34 and from day 0 to day 34 (P<0.01). A reduced feed conversion ratio was observed in the AMT group from day 10 to day 20 (P<0.01). In experiment 2, 96 Stambo HBI×Dalland piglets were weaned at 24 days and assigned to two treatments (the basal diet without the product (CTR) or with 2 g/kg emulsifier from day 0 to day 14 and 1.5 g/kg from day 14 to day 42 (AMT)). There was an increase in the ADFI associated with AMT supplementation from day 14 to day 42 (P=0.04). These results indicated that supplementation with the synthetic emulsifier may significantly improve the growth performance of chickens for fattening and numerically improve that of weaned piglets
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
- …
