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1.
Eur J Investig Health Psychol Educ ; 13(11): 2460-2477, 2023 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-37998062

RESUMO

Effective teaching requires an educational environment that promotes learning, and yet, developing such an environment can be challenging within today's agricultural-based classroom for educators due to the trend to a more virtual teaching format and less hands-on learning. Animal interaction, particularly equine activities, has been shown to assist educators in the development of an emotionally safe environment for promoting learning. However, research is lacking as to whether the interaction with the animal needs to be direct or indirect within the collegiate educational environment to observe benefits. Therefore, the objective of this study was to determine the impact of equine interaction, both direct and indirect, within an educational environment on the emotional safety and learning for the college student within the agricultural-based classroom. Three course types were observed within the agricultural-based educational environment that included courses with no equine interaction (Group A) and courses with equine interaction, both direct (Group B) and indirect (Group C) interaction with the horse. Indirect interaction included items such as observation of equine handling via a video or gaining knowledge from reading online materials, but not engaging in direct, hands-on activities with the horse. Development of emotional safety within the students enrolled within these courses was measured using a self-reporting emotional safety evaluation. Due to the structure of the scale, a decrease in emotional safety indicated a positive change. Learning, both development of semantic and procedural memory, was measured using a student-completed knowledge examination and an instructor-completed skill evaluation, respectively. While significant improvement in emotional safety was not observed within any of the course types, a weak negative correlation was found between emotional safety and semantic memory for students enrolled in equine courses, both direct (R = -0.55, R2 = 0.28) and indirect (R = -0.25, R2 = 0.06) interaction, finding as emotional safety scores lowered to the ideal range that knowledge improved. In addition, students within equine courses showed semantic memory development in specific areas of equine sciences (Group B: Grooming/Tacking, p = 0.03; Group C: Equine Behavior, p = 0.04) and direct equine interaction resulted in development of equine-based procedural memory in all four skill areas measured within the study (p = 0.00). As such, learning is promoted through equine interaction, whether direct or indirect interaction, within the agricultural-based classroom, suggesting that both forms of equine interaction can be a valuable educational tool for the instructor within the collegiate setting.

2.
J Nutr ; 142(3): 456-60, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22279135

RESUMO

Regarded as one of the most versatile amino acids, arginine serves as a precursor for many molecules and has been reported to improve the reproductive performance of rats and pigs. To this end, we sought to determine if dietary L-arginine alters fetoplacental vascular endothelial growth factor receptor-2 (Vegfr2) transcription activity. Eighteen wild-type FVB/N female mice were bred to homozygous FVB/N-Tg(Vegfr2-luc)-Xen male mice. Bred female mice received 1 of 2 experimental diets: one supplemented with 2.00% (wt:wt) L-arginine (+Arg) or 1 supplemented with 4.10% (wt:wt) alanine (+Ala) to serve as an isonitrogenous control for +Arg. In addition, 6 mice were fed a nonsupplemented control (Con) diet to normalize bioluminescent imaging data. All data were analyzed using ANOVA followed by Fisher's least significant difference. Total feed intake did not differ between groups; however, mice in the +Arg group consumed more arginine (P < 0.05). Arginine supplementation increased weight gain during the latter one-third of gestation (d 12- 18), total litter size, number of pups born alive, number of placental attachment sites, litter birth weight, and litter weight of pups born alive but decreased the individual birth weights (P < 0.05). During d 12-18, arginine supplementation increased (P < 0.05) the mean total Vegfr2 transcription activity and Vegfr2 transcription activity corrected for fetoplacental mass. Moreover, mice in the +Arg group had an earlier rise in Vegfr2 transcription activity. In conclusion, our results demonstrate that the beneficial effect of dietary L-arginine supplementation on mammalian reproduction is associated with enhanced Vegfr2 transcription activity in fetoplacental tissues.


Assuntos
Arginina/administração & dosagem , Feto/efeitos dos fármacos , Feto/metabolismo , Placenta/efeitos dos fármacos , Placenta/metabolismo , Reprodução/efeitos dos fármacos , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Animais , Peso ao Nascer/efeitos dos fármacos , Suplementos Nutricionais , Feminino , Tamanho da Ninhada de Vivíparos/efeitos dos fármacos , Masculino , Fenômenos Fisiológicos da Nutrição Materna , Camundongos , Camundongos Transgênicos , Gravidez , Transcrição Gênica/efeitos dos fármacos
3.
Reprod Biol Endocrinol ; 9: 51, 2011 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-21496302

RESUMO

BACKGROUND: Vascular endothelial growth factor receptor-2 (VEGFR2) plays a pivotal role in angiogenesis by eliciting vascular endothelial cell growth when bound to VEGF, a powerful pro-angiogenic ligand. While Vegf and Vegfr2 are expressed throughout gestation, the latter third of gestation in mice is characterized by a marked increase in fetoplacental angiogenesis. Thus, the objective of this study was to determine the feasibility of monitoring fetoplacental Vegfr2 gene activity non-invasively using a Vegfr2-luc reporter transgenic mouse and bioluminescent imaging. METHODS: Imaging parameters were optimized using two wild-type (WT) females, bearing Vegfr2-luc fetuses. Then, seven WT females, bred to Vegfr2-luc males, were imaged from gestational day (GD) 12 to 18 to determine the usefulness of the Vegfr2-luc mouse as a model for studying fetoplacental Vegfr2 activity during pregnancy. Semi-quantitative RT-PCR of Vegfr2 was also performed on whole fetoplacental units during this time. Additionally, resultant neonates were imaged at postnatal day (PND) 7, 14 and 21 to monitor Vegfr2 activity during post-natal development. RESULTS: Fetoplacental Vegfr2 gene activity was detected as light emissions beginning on GD 12 of gestation and increased throughout the imaging period (P < 0.05), and this paralleled the Vegfr2 mRNA data obtained from RT-PCR analysis. A decline in fetoplacental light emissions was associated with a poor pregnancy outcome in one pregnancy, indicating that this approach has potential use for studies monitoring pregnancy well being. Additionally, neonatal Vegfr2 activity was detected at PND 7, 14 and 21 but declined with time (P < 0.0001). CONCLUSIONS: In utero fetoplacental Vegfr2 gene activity was monitored longitudinally in a quantitative manner using a luciferase reporter gene and bioluminescent imaging during the latter third of gestation. This study demonstrates the feasibility of using the Vegfr2-luc mouse to monitor late gestation fetoplacental angiogenic activity under normal and experimental conditions. Additionally, neonatal Vegfr2 gene activity was monitored for three weeks postpartum, allowing continuous monitoring of Vegfr2 activity during the latter third of gestation and postnatal development within the same animals.


Assuntos
Feto/metabolismo , Placenta/metabolismo , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/análise , Imagem Corporal Total/métodos , Animais , Feminino , Desenvolvimento Fetal , Genes Reporter , Processamento de Imagem Assistida por Computador , Luciferases/análise , Luciferases/genética , Luciferases/metabolismo , Camundongos , Camundongos Transgênicos , Modelos Animais , Neovascularização Fisiológica , Gravidez , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/metabolismo
4.
Zoo Biol ; 30(2): 121-33, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-20814990

RESUMO

Endangered giant pandas (Ailuropoda melanoleuca) are bears (Family Ursidae), within the order Carnivora. They specialize on an herbivorous diet of bamboo yet retain a gastrointestinal tract typical of their carnivorous ancestry. The evolutionary constraints of their digestive tract result in a low extraction efficiency from bamboo (<40% in reported studies). The goal of this study was to determine the energy digestibility of bamboo by giant pandas used in digestibility trials and through subsequent analyses with bomb calorimetry. Seven digestibility trials were conducted (three with bamboo-only diets and four with supplemental diets). Energy digestibilities ranged from 7.5-38.9% for mixed diets and 9.2-34.0% for bamboo-only diets. The bamboo-only trials summarized here represent, to our knowledge, the first empirical data available for energy digestibility on a bamboo diet for giant pandas.


Assuntos
Ração Animal/análise , Bambusa/química , Dieta/veterinária , Digestão/fisiologia , Ursidae/fisiologia , Criação de Animais Domésticos , Fenômenos Fisiológicos da Nutrição Animal , Animais , Animais de Zoológico , Bambusa/metabolismo
5.
J Adv Vet Anim Res ; 7(2): 229-233, 2020 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-32607354

RESUMO

OBJECTIVE: This study was conducted to produce and evaluate protected amino acids (AAs) against degradation in the rumen with greater bioavalibility and without the problems associated with polymer coating and the effect this has on calf performance. MATERIALS AND METHODS: In the first step, essential AAs methionine and lysine were reacted with two chemical compounds (Benzaldehyde and Glutaraldehyde) in an attempt to make ligands for producing protected AAs. The physico-chemical characterization, melting point, and mass spectrometric of products were estimated. These products were fed to 36 Holstein dairy calves with 110 ± 0.50 kg of average body weight and an age of 110 ± 10 days. Calves were randomly assigned to six treatments. This study was done with six treatments as a completely randomized one-way design. RESULTS: Feed consumption and average daily gain were less for control animals and those fed methionine and lysine glutaraldehyde compared to other treatments. The largest chewing time was observed for methionine and lysine glutaraldehyde, respectively, and the least was control. There was no difference for energy consumption, dry matter intake, or blood metabolites among the six treatments. The greatest total protein content was related to methionine and lysine glutaraldehyde treatment and the least total protein was observed in control treatment. CONCLUSION: It can be concluded that the use of chemical methods to protect AAs can be applied and may have some beneficial effects.

6.
J Equine Vet Sci ; 64: 41-48, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-30973150

RESUMO

Cecal and ileal cannulations have previously been used to determine equine digestibility and define gastrointestinal physiology. However, research has been limited to specific portions of the equine digestive tract lacking utilization of dual cannulations. The purpose of this study was to develop and implement surgical and preoperative and postoperative procedures for cannulation of dual sections, ileum and cecum, of the equine digestive tract including development of recommendations for addressing postsurgery complications. A total of 8 ponies went through surgical procedures for the placement of a cannula at the ileum and cecum. All ponies awoke from the surgery and stood, but during postsurgical care, complications arisen including increased temperature, dehydration, lameness, herniation, and peritonitis. The survival rate of dual cannulation of the ileum and cecum was 63% of the animals with euthanization attributed to intestinal herniation. This research provides information for the academic community to better plan and implement dual cannulation of equids.

7.
J Anim Sci ; 96(11): 4823-4834, 2018 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-30107547

RESUMO

The objective was to examine uterine artery blood flow (UBF) as well as macroscopic and microscopic placentome vascular density in nutrient-restricted Angus and Brahman heifers. Angus (n = 6) and Brahman (n = 6) heifers were bred to a single sire and pregnancy confirmed at 30-d postbreeding. Heifers were randomly assigned to 1 of 2 dietary treatments consisting of 100% (control-fed; CON; n = 6) or 60% (total nutrient-restricted; RES; n = 6) based from net energy requirements for gestating heifers. Nutritional treatments were imposed from days 50 to 180 of gestation. On day 175 of gestation, UBF was collected ipsilateral and contralateral to the conceptus via Doppler ultrasonography. Heifers underwent Cesarean sections for collection of 2 adjacent placentomes on day 180 of gestation. The primary cotyledonary artery of 1 placentome was perfused with Alexa Fluor 647 Con A conjugate to examine macroscopic cotyledonary vascular density via an in vivo imaging system. The second placentome was fixed for microscopic immunofluorescence labeling of capillaries and separated into maternal (caruncle) and fetal (cotyledon) components for determination of angiogenic factor mRNA expression. Main effects of nutritional treatment and breed are reported in the absence of a significant nutritional treatment by breed interaction. Ipsilateral UBF was decreased (P < 0.05) by 48% in RES vs. CON, whereas breed did not influence ipsilateral UBF. Contralateral UBF was not different between nutritional treatments; however, contralateral UBF was decreased (P < 0.05) by 63% in Brahman vs. Angus cattle. Macroscopic cotyledonary vascular density was increased (P < 0.05) by 36% in RES vs. CON and 82% in Brahman vs. Angus heifers. Percent capillary area and capillary perimeter were increased (P < 0.05) in RES vs. CON and increased (P < 0.05) in Brahman vs. Angus heifers. Dietary treatments did not alter angiogenic factor expression; however, transcript abundance of caruncle and cotyledon ANGP1, FLT1, and KDR was increased (P < 0.05) in Brahman vs. Angus heifers. In summary, these data indicate compensatory responses in macroscopic and microscopic placentome blood vessel density during maternal nutrient restriction-induced reductions in UBF. Moreover, a greater macroscopic density of cotyledonary blood vessels was observed in Brahman vs. Angus heifers.


Assuntos
Bovinos/fisiologia , Fenômenos Fisiológicos da Nutrição Materna , Animais , Dieta/veterinária , Feminino , Hemodinâmica , Nutrientes , Placenta/irrigação sanguínea , Gravidez , Distribuição Aleatória , Artéria Uterina/efeitos dos fármacos , Útero/irrigação sanguínea
8.
Front Plant Sci ; 7: 151, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26909094

RESUMO

Gregarious flowering of bamboo species impacts ecosystem properties and conservation, but documentation of these periodic events is difficult. Here, we compare the characteristics of flowering sites and un-flowered patches of an arrow bamboo (Fargesia qinlingensis) in the Qinling Mountains, China, over a 5-year period (2003-2007) after a mast flowering event (2003). We examined flowering culm and seedling characteristics in relation to questions regarding the evolution of delayed flowering. Density of live culms decreased over the 5 years in both flowering sites and un-flowered patches. New shoots regenerated only in un-flowered patches. Chemical constituent allocation varied among culm parts (stems, branches, and leaves). Crude protein and extract ether in branches and leaves were less in flowering culms than in un-flowered culms. Seedling density was lower than expected based on floret counts, suggesting predation of seeds. Seedling density was significantly greater in flowering sites than in un-flowered patches and decreased over time. Seedlings performed better in flowering sites than in un-flowered patches based on their height, leaf number per seedling, and average leaf length, while fertilization on flowering sites had no significant effect on seedling growth, suggesting a saturation of resources. This study suggested that the characteristics of bamboos and bamboo stands were dramatically altered during this flowering event, enhancing seedling establishment and growth, and supporting mostly the habitat modification hypothesis of delayed reproduction.

9.
Springerplus ; 5(1): 888, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27386336

RESUMO

Muscle growth requires a constant supply of amino acids (AAs) from the blood. Therefore, plasma AA profile is a critical factor for maximizing the growth performance of animals, including pigs. This research was conducted to study how dietary lysine intake affects plasma AA profile in pigs at the late production stage. Eighteen crossbred (Large White × Landrace) finishing pigs (nine barrows and nine gilts; initial BW 92.3 ± 6.9 kg) were individually penned in an environment controlled barn. Pigs were assigned randomly to one of the three dietary treatments according to a randomized complete block design with sex as block and pig as experiment unit (6 pigs/treatment). Three corn- and soybean meal-based diets contained 0.43 % (lysine-deficient, Diet I), 0.71 % (lysine-adequate, Diet II), and 0.98 % (lysine-excess, Diet III) l-lysine, respectively. After a 4-week period of feeding, jugular vein blood samples were collected from the pigs and plasma was obtained for AA analysis using established HPLC methods. The change of plasma lysine concentration followed the same pattern as that of dietary lysine supply. The plasma concentrations of threonine, histidine, phenylalanine, isoleucine, valine, arginine, and citrulline of pigs fed Diet II or III were lower (P < 0.05) than that of pigs fed Diet I. The plasma concentrations of alanine, glutamate, and glycine of pigs fed Diet II or III were higher (P < 0.05) than that of pigs fed Diet I. The change of plasma leucine and asparagine concentrations followed the patterns similar to that of plasma lysine. Among those affected AAs, arginine was decreased (P < 0.05) in the greatest proportion with the lysine-excess diet. We suggest that the skeletal muscle growth of finishing pigs may be further increased with a lysine-excess diet if the plasma concentration of arginine can be increased through dietary supplementation or other practical nutritional management strategies.

10.
Plants (Basel) ; 3(2): 266-83, 2014 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-27135504

RESUMO

Interest in management of native warm-season grasses for multiple uses is growing in southeastern USA. Forage quality response of early-succession mixed stands of big bluestem (BB, Andropogon gerardii), indiangrass (IG, Sorghastrum nutans), and little bluestem (SG, Schizachyrium scoparium) to harvest intervals (30-, 40-, 60-, 90 or 120-d) and durations (one or two years) were assessed in crop-field buffers. Over three years, phased harvestings were initiated in May, on sets of randomized plots, ≥90 cm apart, in five replications (blocks) to produce one-, two-, and three-year-old stands, by the third year. Whole-plot regrowths were machine-harvested after collecting species (IG and LB) sample tillers for leafiness estimates. Species-specific leaf area (SLA) and leaf-to-stem ratio (LSR) were greater for early-season harvests and shorter intervals. In a similar pattern, whole-plot crude protein concentrations were greatest for the 30-d (74 g·kg(-1) DM) and the least (40 g·kg(-1) DM) for the 120-d interval. Corresponding neutral detergent fiber (NDF) values were the lowest (620 g·kg(-1) DM) and highest (710 g·kg(-1) DM), respectively. In vitro dry matter and NDF digestibility were greater for early-season harvests at shorter intervals (63 and 720 g·kg(-1) DM). With strategic harvesting, similar stands may produce quality hay for beef cattle weight gain.

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