Growth Performance of Holstein Dairy Calves Supplemented with a Probiotic

Administration of antibiotics in both therapeutic and sub-therapeutic doses has been the standard practice for dealing with pathogenic bacteria problems in farm animals since the 1940s. Several types of antibiotics are currently used to promote weight gain and feed efficiency in domestic livestock. There is growing concern that the use of antibiotics as growth promoters may result in the development of resistant populations of pathogenic bacteria and, in turn, influence the therapeutic use of antibiotics. The indiscriminate and improper use of antibiotics in food-producing animals could result in the presence of residues in milk, meat, and other animal food products consumed by humans. One possible alternative to antibiotics is the use of probiotics. Probiotics can be defined as “live microbial feed supplements which beneficially affect the host animal by improving its intestinal microbial balance” (Fuller, 1989). Probiotics introduce beneficial microorganisms into the gut which act to maintain optimal conditions within the gastrointestinal tract and inhibit the growth of pathogenic or other undesirable bacteria

Rumen Microbial Protein Synthesis in Cows Fed Dried Whey

Two rumen fistulated Holstein cows, weighing approximately 550 kg, were used in a switchback design experiment to evaluate the effects of consuming large amounts (38% of total ration dry matter) of dried whey on rumen microbial protein synthesis. Cows were fed total mixed rations consisting of (dry matter basis) 45% corn silage, 10% alfalfa hay, and 45% concentrate mix. The concentrate mix was primarily corn and soybean meal (control) or 85% dried whole whey. Dry matter intakes averaged 16.4 and 15.3 kg/day for control and whey diets. Concentrations of bacteria and protozoa in rumen contents were estimated using diaminopimelic acid and aminoethylphosphonic acid, respectively, as markers. Diaminopimelic acid-N as percent of bacterial-N was similar for both diets (.61 and .63% for control and whey diets). Likewise, aminoethylphosphonic acid-N as percent of protozoal-N was similar for both diets (.17 and .19% for control and whey diets). For the control diet, total rumen-N was estimated to be 45% bacterial-N and 27% protozoal-N. Bacterial-N and protozoal-N, respectively, accounted for 52 and 22% of the total rumen-N in the cows fed the whey diet. Rumen fluid volume (33.8 and 39.2 liters for control and dried whey diets) and dilution rates (10.2 and 12.8%/h), as estimated with polyethylene glycol, were higher when fed dried whey. Rumen ammonia (5.0 and 3.4 mg/dl) was lower when fed dried whey. Butyrate (16.5 and 24.4 moles/100 moles total volatile fatty acids) was higher while propionate was lower (32.4 and 23.2 moles/100 moles total volatile fatty acids) when fed dried whey; concentrations of other volatile fatty acids were similar with both diets. Bacterial synthesis appeared to be increased when cows were fed a diet containing large amounts of dried whey

Behaving Optimistically: How the (Un)Desirability of an Outcome Can Bias People’s Preparations for It

Past research on the desirability bias and on bracing for bad news has focused on the potential influence of outcome desirability on people’s stated expectations. The present studies examined its influence on behavior—that is, what is done in anticipation of, or preparation for, an uncertain outcome. In five studies, the desirability of possible outcomes for an event, which was uncertain and uncontrollable by the participant, was manipulated, and preparation behavior was measured. Study 1 used a hypothetical‐events paradigm. Studies 2 and 3 involved a computer activity in which behavior was tracked on a trial‐by‐trial basis. In Studies 4 and 5, the uncertain event was the ending of a videotaped basketball game. Rather than exhibiting bracing or a reluctance to tempt fate, participants tended to behave in a manner consistent with an optimistic desirability bias. In a subset of studies, predictions and likelihood judgments were also solicited; the differential effects of outcome desirability on these measures are discussed. Copyright © 2015 John Wiley & Sons, Ltd.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/135587/1/bdm1918_am.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/135587/2/bdm1918.pd

Towards a Strategy to Fight the Computer Science (Cs) Declining Phenomenon

International audienceEuropean students have give reasons why they reject computer science (CS) as a program of study in higher education [1]. The constant decrease in the number of students choosing to study this subject has had consequences in different European sectors, such as the economic sector or the education sector, among others [2]. Some of the reasons for this rejection are related to the degree of difficulty of the skills that are needed to master CS. This study aims to identify these skills by firstly comparing CS curricula across several European universities and then comparing these curricula with same level programs in other areas of study. It will highlight some misconceptions students have concerning CS programs and will demonstrate that Technology Enhanced Learning (TEL) may have a major role to play in combating the decline of CS professionals by providing dynamic learning environments; where students can acquire the knowledge and skills which are unique to the field of CS

A quantum theory account of order effects and conjunction fallacies in political judgments

Are our everyday judgments about the world around us normative? Decades of research in the judgment and decision-making literature suggest the answer is no. If people's judgments do not follow normative rules, then what rules if any do they follow? Quantum probability theory is a promising new approach to modeling human behavior that is at odds with normative, classical rules. One key advantage of using quantum theory is that it explains multiple types of judgment errors using the same basic machinery, unifying what have previously been thought of as disparate phenomena. In this article, we test predictions from quantum theory related to the co-occurrence of two classic judgment phenomena, order effects and conjunction fallacies, using judgments about real-world events (related to the U.S. presidential primaries). We also show that our data obeys two a priori and parameter free constraints derived from quantum theory. Further, we examine two factors that moderate the effects, cognitive thinking style (as measured by the Cognitive Reflection Test) and political ideology

Evaluating a Modeling Curriculum by Using Heuristics for Productive Disciplinary Engagement

The BIO2010 report provided a compelling argument for the need to create learning experiences for undergraduate biology students that are more authentic to modern science. The report acknowledged the need for research that could help practitioners successfully create and reform biology curricula with this goal in mind. Our objective in this article was to explore how a set of six design heuristics could be used to evaluate the potential of curricula to support productive learning experiences for science students. We drew on data collected during a long-term study of an undergraduate traineeship that introduced students to mathematical modeling in the context of modern biological problems. We present illustrative examples from this curriculum that highlight the ways in which three heuristics—instructor role-modeling, holding students to scientific norms, and providing students with opportunities to practice these norms—consistently supported learning across the curriculum. We present a more detailed comparison of two different curricular modules and explain how differences in student authority, problem structure, and access to resources contributed to differences in productive engagement by students in these modules. We hope that our analysis will help practitioners think in more concrete terms about how to achieve the goals set forth by BIO2010

Epistemological framing and novice elementary teachers’ approaches to learning and teaching engineering design

As engineering learning experiences increasingly begin in elementary school, elementary teacher preparation programs are an important site for the study of teacher development in engineering education. In this article, we argue that the stances that novice teachers adopt toward engineering learning and knowledge are consequential for the opportunities they create for students. We present a comparative case study examining the epistemological framing dynamics of two novice urban teachers, Ana and Ben, as they learned and taught engineering design during a four‐week institute for new elementary teachers. Although the two teachers had very similar teacher preparation backgrounds, they interpreted the purposes of engineering design learning and teaching in meaningfully different ways. During her own engineering sessions, Ana took up the goal not only of meeting the needs of the client but also of making scientific sense of artifacts that might meet those needs. When facilitating students’ engineering, she prioritized their building knowledge collaboratively about how things work. By contrast, when Ben worked on his own engineering, he took up the goal of delivering a product. When teaching engineering to students, he offered them constrained prototyping tasks to serve as hands‐on contexts for reviewing scientific explanations. These findings call for teacher educators to support teachers’ framing of engineering design as a knowledge building enterprise through explicit conversations about epistemology, apprenticeship in sense‐making strategies, and tasks intentionally designed to encourage reasoning about design artifacts.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/151339/1/tea21541_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/151339/2/tea21541.pd