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Zhang T.,University of North Carolina at Greensboro | Chen A.,University of North Carolina at Greensboro | Chen S.,Lowa State University | Hong D.,University of Northern Iowa | And 2 more authors.
European Physical Education Review | Year: 2014

In physical education, it has become necessary for children to learn kinesiological knowledge for understanding the benefits of physical activity and developing a physically active lifestyle. This study was conducted to determine the extent to which cognitive assignments about healthful living and fitness contributed to knowledge growth on cardiorespiratory fitness and health. Fourth grade students (N = 616) from 15 randomly sampled urban elementary schools completed 34 cognitive assignments related to the cardiorespiratory physical activities they were engaged in across 10 lessons. Performance on the assignments were analyzed in relation to their knowledge gain measured using a standardized knowledge test. A multivariate discriminant analysis revealed that the cognitive assignments contributed to knowledge gain but the contribution varied assignment by assignment. A multiple regression analysis indicated that students’ assignment performance by lesson contributed positively to their knowledge growth scores. A content analysis based on the constructivist learning framework showed that observing–reasoning assignments contributed the most to knowledge growth. Analytical and analytical–application assignments contributed less than the constructivist theories would predict. © The Author(s) 2014. Source

Johnson S.K.,Kansas State University | Dahike G.,Lowa State University
Professional Animal Scientist | Year: 2016

An online survey of AI users was developed to determine how industry segment (commercial, seedstock, ormultiple segments) influenced profitability and current management practices used in conjunction with AI and estrus synchronization in the United States beef industry. Survey results came from 42 states and included 425 completed instruments. Value of replacement heifers (80%) and reducing calving difficulty (55%) were the most common ways AI contributed to profitability. Commercial producers ($187 ± 79) assigned a lower (P < 0.05) value to Al-sired calves than did seedstock producers ($709 ± 63). Producers used estrus synchronization always (46%), usually (26%), sometimes (28%), rarely (6%), or never (4%). Insemination after observed estrus was the most common method of insemination (42%), followed by single fixed-time AI (34%), and then AI after observed estrus with cleanup timed AI (24%). The most frequently used system for synchroniza tion of estrus in cows and heifers was a 7-d CO-Synch + controlled internal drug-releasing insert protocol. Use of reproductive tract scoring, temporary calf removal, and natural service sires on synchronized heats was relatively low, ranging from 20 to 28%, and did not differ among industry subgroups. Seedstock producers were 2.5-times more likely (P < 0.05) to use pelvic measurements than commercial producers. Producers identified nutrition, heat detection, and skilled labor as key components of successful AI programs. Survey data pointed to opportunities to increase producer awareness on management issues related to AI and estrus synchronization, in particular, the success and convenience of fixed-time insemination protocols. © 2016 American Registry of Professional Animal Scientists. Source

Gunn P.J.,Lowa State University | Culp K.C.,Purdue University | Culp K.C.,The Andersons | Lemenager R.P.,Purdue University | Bridges G.A.,University of Minnesota
Professional Animal Scientist | Year: 2016

Fixed timed-AI (TAI) pregnancy rates were compared in suckled beef cows (n=883; 5 replications) synchronized using the 5-d CO-Synch protocol with (CDR) or without (NCDR) the inclusion of exogenous progesterone (EAZIBREED CIDR insert; CIDR). Cows were assigned to either the CDR (n=445) or NCDR (n=438) treatment by breed, parity, and days postpartum. Blood samples were collected 10 d before and immediately before CIDR insertion (d 0) to determine cyclic status. On d 0 all cows received gonadotropin-releasing hormone (100 fg), and cows in the CDR treatment received a CIDR. On d 5, CIDR were removed in CDR treatment and all cows received 2 separate doses of prostaglandin Fga (25 mg/dose). Cows were TAI 72 h after CIDR removal (d 8), concurrent with gonadotropin-releasing hormone (100 fg). The proportion of females determined to be cyclic before estrous synchronization was 87.1% (757/869). Timed-AI pregnancy rates were greater (P=0.05) in CDR (62.3%, n=438) than NCDR (50.7%, n=436) treatment. However, a treatment x parity interaction (P=0.08) was noted relative to TAI. Although CDR obtained greater (P<0.01) TAI pregnancy rates than NCDR in both primiparous and multiparous groups, difference between treatments was greater in primiparous females (69.0 vs. 46.3% for CDR and NCDR, respectively) than multiparous females (60.7 vs. 51.7% for CDR and NCDR, respectively). To optimize TAI pregnancy rates in beef cows synchronized with the 5-d CO-Synch protocol, inclusion of a CIDR is recommended. © 2016 American Registry of Professional Animal Scientists. Source

Liu Q.,Chinese Academy of Agricultural Sciences | Wang J.,Chinese Academy of Agricultural Sciences | Bu D.,Chinese Academy of Agricultural Sciences | Khas-Erdene,Chinese Academy of Agricultural Sciences | And 4 more authors.
Journal of Agricultural and Food Chemistry | Year: 2010

Increasing the content of α-linolenic acid in milk fat might be desirable to meet consumer concerns about dietary healthfulness. However, the rich content of polyunsaturated fatty acids (PUFAs) will influence the oxidative stability of milk fat. This experiment was carried out to determine the effects of infusion with different amounts of high-linolenic perilla fatty acid (HLPFA) emulsion into the duodenum of dairy cows on milk fatty acid profile and the susceptibility of milk fat to oxidation. In a crossover design, 4 multiparous Holstein cows were infused duodenally with increasing amounts (0, 40, 80, 120, or 160 g/day) of free fatty acids from HLPFA emulsion or with carrier alone. Continuous infusions (20 to 22 h/day) were for 7 days at each amount. Infusions were homogenates of HLPFA with 15 g/day of xanthan gum, 5 g/day sodium alginate, and 25 g/day Tween 80; controls received carrier only. The concentration of n-3 PUFAs, especially α-linolenic acid, in milk fat increased linearly as HLPFA infusion increased, but the saturated fatty acids decreased linearly. The milk production and the activity of superoxide dismutase, glutathione peroxidase, and catalase in milk tended to decrease quadratically. The milk fat percentage, however, tended to increase. The concentration of malondialdehyde increased quadratically in milk fat. Results suggest that infusion with HLPFA emulsion at varying amounts enhanced the content of n-3 PUFAs in milk fat over the length of experiment but decreased the oxidative stability of milk fat. ©2010 American Chemical Society. Source

Perera O.P.,U.S. Department of Agriculture | Blanco C.A.,U.S. Department of Agriculture | Ballard L.,Genomics and Bioinformatics Research Unit | Silva-Brandao K.L.,University of Sao Paulo | And 2 more authors.
Southwestern Entomologist | Year: 2011

Polymorphic genetic markers were identified and characterized using a partial genomic library of the tobacco budworm, Heliothis virescens (Fabricius), enriched for simple sequence repeats (SSR) and nucleotide sequences of expressed sequence tags (EST). Nucleotide sequences of 192 clones from the partial genomic library yielded 147 unique SSRs while EST evaluations identified 280 SSR-containing sequences. All anonymous SSRs and 192 EST-SSRs were evaluated to select loci that produced the best quality peaks without stutter peaks. Six anonymous markers and nine EST-derived markers were selected to evaluate a sample of 96 insects collected from Stoneville, MS. The observed number of alleles ranged from two to eight, with an average of 5.87 (SE ± 0.53). The polymorphic information content (PIC) value averaged 0.446 (SE ± 0.052). Significant deviations from Hardy-Weinberg expectations were detected at eight loci. We speculate that these loci are under selection in the population of tobacco budworm used in the study. No significant linkage disequilibrium was detected at any of the loci. Proportions of anonymous and EST-SSR markers validated after extensive evaluation were 4.08 and 4.68%, respectively. One anonymous SSR marker (HvMS117) and all nine EST markers were transferable to the bollworm, Helicoverpa zea (Boddie). Copyright © 2011 BioOne All rights reserved. Source

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