Effects of nutrition on digestión efficicency and gaseous emissions from slurry in growing-finishing pigs. I. Influence of the inclusión of two levels of orange pulp and carb meal in isofibrous diets

An experiment was conducted to investigate the effects of increasing the level of two sources of fibrous by-products, orange pulp (OP) and carob meal (CM), in iso-NDF growing-finishing pig diets on nutrient balance, slurry composition and potential ammonia (NH3) and methane (CH4) emissions. Thirty pigs (85.4 ± 12.3 kg) were fed five iso-nutritive diets: a commercial control wheat/barley (C) and four experimental diets including two sources of fibrous by-products (OP and CM) and two dietary levels (75 and 150 g/kg) in a 2 × 2 factorial arrangement. After a 14-day adaptation period, faeces and urine were collected separately for 7 days to measure nutrient digestibility and the excretory patterns of N from pigs (6 replicates per diet) housed individually in metabolic pens. For each animal, the derived NH3 and CH4 emissions were measured in samples of slurry over an 11- and 100-day storage periods, respectively. Source and level of the fibrous by-products affected digestion efficiency in a different way as the coefficients of total tract apparent digestibility (CTTAD) for dry matter (DM), organic matter (OM), fibre fractions and gross energy increased with OP but decreased with CM (P < 0.05). Crude protein CTTAD decreased with the inclusion of both sources of fibre, being lower at the highest dietary level. Faecal concentration of fibre fractions increased (P < 0.05) with the level of inclusion of CM but decreased with that of OP (P < 0.01). High dietary level for both sources of fibre increased (P < 0.02) CP faecal content but urine N content decreased (from 205 to 168 g/kg DM, P < 0.05) in all the fibre-supplemented compared to C diet. Additionally, the proportions of undigested dietary, water soluble, and bacterial and endogenous debris of faecal N excretion were not affected by treatments. The initial slurry characteristics did not differ among different fibre sources and dietary levels, except pH, which decreased at the highest by-product inclusion levels. Ammonia emission per kg of slurry was lower in all the fibre-supplemented diets than in C diet (from 2.44 to 1.81 g, P < 0.05). Additionally, slurries from the highest dietary level of by-products tended (P < 0.06) to emit less NH3 per kg of initial total Kjeldahl N and showed a lower B0, independently of the fibre source. Thus, the fibre sources and their dietary levels affected pig nutrient digestion and composition of urine and faeces, showing potential to decrease NH3 and CH4 emissions at high levels of inclusion, independently of type of fibre.

Effects of nutrition on digestión efficiency and gaseous emissions from slurry in growing pigs: III. Influence of varying the dietary level of calcium soap of palm fatty acids distillate with or without orange pulp supplemention

The aim of this study was to establish the relationships between faecal fat concentration and gaseous emissions from pig slurry. Five diets were designed to meet essential nutrient requirements: a control and four experimental feeds including two levels (35 or 70 g/kg) of calcium soap fatty acids distillate (CSP) and 0 or 200 g/kg of orange pulp (OP) combined in a 2 × 2 factorial structure. Thirty growing pigs (six per treatment) were used to measure dry matter (DM) and N balance, coefficients of total tract apparent digestibility (CTTAD) of nutrients, faecal and urine composition and potential emissions of ammonia (NH3) and methane (CH4). Increasing dietary CSP level decreased DM, ether extract (EE) and crude protein (CP) CTTAD (by 4.0, 11.1 and 3.5%, respectively, P < 0.05), but did not influence those of fibrous constituents. It also led to a decrease (from 475 to 412 g/kg DM, P < 0.001) of faecal concentration of neutral detergent fibre (aNDFom) and to an increment (from 138 to 204 g/kg, P < 0.001) of EE in faecal DM that was related to greater CH4 emissions, both per gram of organic matter (P = 0.021) or on a daily basis (P < 0.001). Level of CSP did not affect N content in faeces or urine, but increased daily DM (P < 0.001), and N (P = 0.031) faecal excretion with no effect on urine N excretion. This resulted in lesser (P = 0.036) NH3 potential emission per kg of slurry. Addition of OP decreased CTTAD of EE (by 7.9%, P = 0.044), but increased (P < 0.05) that of all the fibrous fractions. As a consequence, faecal EE content increased (from 165 to 177 g/kg DM; P = 0.012), and aNDFom decreased greatly (from 483 to 404 g/kg DM, P < 0.001), which in all resulted in a lack of effect of OP on CH4 potential emission. Inclusion of OP in the diet also led to a significant decrease of CP CTTAD (by 6.85%, P < 0.001), and to an increase of faecal CP concentration (from 174 to 226 g/kg DM, P < 0.001), with no significant influence on urine N content. These effects resulted in higher N faecal losses, especially those of the undigested dietary origin, without significant effects on potential NH3 emission. No significant interactions between CSP and OP supplementation were observed for the gaseous emissions measured.

Effects of nutrition on digestión efficicency and gaseous emissions from slurry in growing-finishing pigs. II. Effect of protein source in practical diets.

Uso de diferentes fuentes de proteína en la alimentación de cerdos en fase de cebo y su relación con las emisiones de gases amoniaco y metano.

The effect of slurry composition on methane potential emissions from fattening pig slurries: a review of three nutrition assays

This study reviews the effects of pig slurry composition on the biochemical methane (CH4) potential (B0), using the information collected in three nutrition assays. A total of 84 animals were used to test the effect of 13 different diets.

Acclimation of Photosynthesis to Elevated CO2 under Low-Nitrogen Nutrition Is Affected by the Capacity for Assimilate Utilization. Perennial Ryegrass under Free-Air CO2 Enrichment1

Acclimation of photosynthesis to elevated CO2 has previously been shown to be more pronounced when N supply is poor. Is this a direct effect of N or an indirect effect of N by limiting the development of sinks for photoassimilate? This question was tested by growing a perennial ryegrass (Lolium perenne) in the field under elevated (60 Pa) and current (36 Pa) partial pressures of CO2 (pCO2) at low and high levels of N fertilization. Cutting of this herbage crop at 4- to 8-week intervals removed about 80% of the canopy, therefore decreasing the ratio of photosynthetic area to sinks for photoassimilate. Leaf photosynthesis, in vivo carboxylation capacity, carbohydrate, N, ribulose-1,5-bisphosphate carboxylase/oxygenase, sedoheptulose-1,7-bisphosphatase, and chloroplastic fructose-1,6-bisphosphatase levels were determined for mature lamina during two consecutive summers. Just before the cut, when the canopy was relatively large, growth at elevated pCO2 and low N resulted in significant decreases in carboxylation capacity and the amount of ribulose-1,5-bisphosphate carboxylase/oxygenase protein. In high N there were no significant decreases in carboxylation capacity or proteins, but chloroplastic fructose-1,6-bisphosphatase protein levels increased significantly. Elevated pCO2 resulted in a marked and significant increase in leaf carbohydrate content at low N, but had no effect at high N. This acclimation at low N was absent after the harvest, when the canopy size was small. These results suggest that acclimation under low N is caused by limitation of sink development rather than being a direct effect of N supply on photosynthesis.

The Impact of Repetitive Concussions In High School Athletes

Concussive injuries appear to be becoming a more common occurrence among athletes. While many studies have assessed the short-term and long-term effects of concussive injuries, fewer studies have specifically addressed the impact of multiple concussive injuries within a high school population. Through the use of the Immediate Post-Concussion Assessment and Cognitive Testing measure (ImPACT), this study investigated differences in a sample of 946 high school athletes with varying concussive histories (multiple concussions vs. single concussion vs. no concussion) at baseline and following sustaining a concussive injury. An additional analysis was conducted with athletes who obtained two concussions within the study to assess for trends in symptomology between their first and second injuries. For both baseline and study concussed athletes, athletes with multiple concussive injuries did not exhibit significantly elevated self-report symptoms nor decreased ImPACT composite scores compared to the other groups. Analysis of data from athletes who sustained more than one concussion within the study, revealed an increase in self-report symptoms and a decrease in ImPACT performance from time 1 to time 2. However, these changes were small in magnitude and were not consistently exhibited across the variables under investigation. Overall, this study did not find compelling evidence of increased symptomological patterns or decreased functioning for multiple concussed athletes as compared to peers.

Exploring the Experiences of International Student-Athletes

According to the latest National Collegiate Athletic Association (NCAA) Student Athlete Ethnicity Report, there are 17,653 non-US citizen student-athletes competing in various sports in universities across the country, yet there is very little research to understand their experiences (NCAA, 2010). Previous research has focused on recruitment practices (Bale, 1991; Pierce, Popp, & Meadows, 2011), satisfaction (Trendafilova, Kim, & Hardin, 2010), and adjustment and transitional factors (Pierce, Popp, & Meadows, 2011; Popp, Love, Kim, & Hums, 2010; Ridinger & Pastore, 2000), with a void in examining their overall experiences. Therefore, purpose of this qualitative study was to explore the experiences of international student-athletes in the United States within their athletic department and universities, as well as in the country. Participants were solicited by email, and ultimately six (n = 6) international student-athletes from a Division-I university chose to participate in the study and represented two different countries of origin, Canada and Norway. Participants completed a semi-structured interview, consisting of one broad open-ended question followed by a series of specific follow-up questions. Content analysis revealed that most participants did not consider their experiences different than domestic student-athletes. Challenges shared by most athletes included language barriers, balancing their time, and homesickness. Results also revealed the importance of interpersonal connections, especially with coaches and athletes from the international student-athlete's home country, in ensuring a positive overall experience. Implications of this study are that individuals and professionals working in campus offices associated with international student-athletes should be mindful of their unique roles within the university in order to foster positive experiences and retention.

Examining the Relationship Between Passion and Perceptions of Cohesion in Athletes

The purpose of the present study was to examine the relationship of harmonious and obsessive passion to perceptions of task and social cohesion in team sport athletes. Participants were 370 competitive (N=252) and recreational (N=118) athletes ranging from 18- to 28-years-old (Mage=20.20, SD=1.52) from a wide variety of team sports. Participants completed the Passion Scale (Vallerand et al., 2003) and the Group Environment Questionnaire (Carron et al., 1985). A MANOVA revealed that competitive athletes were more passionate and had higher perceptions of cohesion than did recreational athletes. Multiple regression analyses revealed a positive relationship between both harmonious and obsessive passion and both task (ATG-T, GI-T) and social (ATG-S, GI-S) cohesion. Theoretical and practical implications are discussed pertaining to the importance of harmonious and obsessive passion in athletes and perceptions of cohesion in competitive and recreational sport.

The Role of Enjoyment and Motivational Climate in Relation to the Personal Development of Team Sport Athletes

Sport has been identified as a context in which youth encounter positive and negative experiences. However, relatively little is known about the factors that lead to positive and negative personal development among sport participants. The purpose of this study was to investigate the role of enjoyment and motivational climate on positive and negative personal development of team sport participants. A sample of 510 athletes between the ages of 9 and 19 completed questionnaires on positive and negative personal development, enjoyment, and motivational climate. Stepwise multiple regression analyses examined the effects of enjoyment and motivational climate on the personal development of the athletes. Results demonstrated that positive experiences in sport were most strongly predicted by affiliation with peers, self-referenced competency, effort expenditure, and a task climate. Negative experiences were most strongly predicted by an ego climate and other-referenced competency. Results suggest that creating an environment that encourages peer affiliation and personal achievement can result in the positive personal development of youth sport participants.

Effective Behaviors of Expert Rowing Coaches: A Qualitative Investigation of Canadian Athletes and Coaches

Ten Canadian expert rowing coaches and 10 Canadian elite rowers were interviewed regarding their perceptions of effective coaching behaviors. The questions of the interview guide focused on coaches' behaviors in training, competition, and organization settings. Qualitative data analyses revealed seven behaviors elicited by coaches and athletes. Effective coaching behaviors perceived as important by both athletes and coaches were; 1) plan proactively, 2)create a positive training environment, 3)facilitate goal setting, 4)build athletes' confidence, 5) teach skills effectively, 6)recognize individual differences, and 7)establish a positive rapport with each athlete.