College of Agriculture and Life Sciences (CALS)

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Browsing College of Agriculture and Life Sciences (CALS) by Department "Animal and Poultry Sciences"

Now showing 1 - 20 of 336
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    Activity Dependent Protein Degradation Is Critical for the Formation and Stability of Fear Memory in the Amygdala
    Jarome, Timothy J.; Werner, Craig T.; Kwapis, Janine L.; Helmstetter, Fred J. (PLOS, 2011-09)
    Protein degradation through the ubiquitin-proteasome system [UPS] plays a critical role in some forms of synaptic plasticity. However, its role in memory formation in the amygdala, a site critical for the formation of fear memories, currently remains unknown. Here we provide the first evidence that protein degradation through the UPS is critically engaged at amygdala synapses during memory formation and retrieval. Fear conditioning results in NMDA-dependent increases in degradationspecific polyubiquitination in the amygdala, targeting proteins involved in translational control and synaptic structure and blocking the degradation of these proteins significantly impairs long-term memory. Furthermore, retrieval of fear memory results in a second wave of NMDA-dependent polyubiquitination that targets proteins involved in translational silencing and synaptic structure and is critical for memory updating following recall. These results indicate that UPS-mediated protein degradation is a major regulator of synaptic plasticity necessary for the formation and stability of long-term memories at amygdala synapses.
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    Acute heat stress activated inflammatory signaling in porcine oxidative skeletal muscle
    Ganesan, Shanthi; Volodina, Olga; Pearce, Sarah C.; Gabler, Nicholas K.; Baumgard, Lance H.; Rhoads, Robert P.; Selsby, Joshua T. (2017-08)
    Despite well-studied clinical manifestations, intracellular mechanisms of prolonged hyperthermic injury remain unclear, especially in skeletal muscle. Given muscle's large potential to impact systemic inflammation and metabolism, the response of muscle cells to heat-mediated injury warrants further investigation. We have previously reported increased activation of NF-κB signaling and increased NF-κB and AP-1-driven transcripts in oxidative skeletal muscle following 12 h of heat stress. The purpose of this investigation was to examine early heat stress-induced inflammatory signaling in skeletal muscle. We hypothesized that heat stress would increase NF-κB and AP-1 signaling in oxidative skeletal muscle. To address this hypothesis, 32 gilts were randomly assigned to one of four treatment groups (n = 8/group): control (0 h: 21°C) or exposed to heat stress conditions (37°C) for 2 h (n = 8), 4 h (n = 8), or 6 h (n = 8). Immediately following environmental exposure pigs were euthanized and the red portion of the semitendinosus muscle (STR) was harvested. We found evidence of NF-κB pathway activation as indicated by increased protein abundance of NF-κB activator IKK-α following 4 h and increased total NF-κB protein abundance following 6 h of heat stress. Heat stress also stimulated AP-1 signaling as AP-1 protein abundance was increased in nuclear fractions following 4 h of heat stress. Interleukin-6 protein abundance and activation of the JAK/STAT pathway were decreased in heat stressed muscle. These data indicate that heat stress activated inflammatory signaling in the porcine STR muscle via the AP-1 pathway and early activation of the NF-κB pathway.
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    Additional Molecular Evidence that The Royal Palm is Probably a Turkey Breed
    Smith, Edward J.; Xu, Jun; Adikari, J. (2019-07-09)
    In earlier investigations, we reported the uniqueness of Royal Palm from other commonly raise heritage turkeys. Here, we provide evidence from screening using primers specific for the Melanocortin 1 (MC1R) Receptor gene (located on turkey chromosome 13, accession number NC_015023). Five heritage strains, including Broad Breasted Bronze (48), Blue Slate (40), Midget White (40), Royal Palm (45), and Spanish Black (48) were included in the analyses of approximately 3300 base pairs of the MC1R gene. Seven SNPs were identified and validated. Among the haplotypes identified, only Royal Palm had unique haplotypes. When combined with previous investigations, we believe that the Royal Palm may be a breed and not a strain. It may therefore be the most viable resource for introgression with a goal of genetic improvement.
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    Advancing livestock genomics education and research in developing countries using strategies from the Virginia Tech PREP and IMSD training programs
    Smith, Edward J. (2019-07-11)
    Our unique and impactful research and education program plan includes distinct activities that target three overlapping phases of each trainee’s tenure, which we define as the “moving in,” “moving through,” and “moving out” phases. During the “moving in” phase, 8 trainees “who need a PREP” will be recruited and assigned to mentors using our proven strategy that is “scholar-driven” and combines mentor qualities such as prior experience, which has resulted in a 98% retention for each of our 3 funding cycles.  $409,537 annually or ~2.1 Million for five years. our successful interdisciplinary Initiative for Maximizing Student Development (IMSD) program for pre-doctoral (graduate) and pre-baccalaureate (undergraduate) students from groups underrepresented in careers in the biomedical and behavioral sciences. Our training program is a partnership with departments and interdisciplinary graduate programs which takes advantage of Virginia Tech’s (VT) history of excellence in Engineering and the Behavioral and Life Sciences. With lessons learned in the last eight years, we will continue to recruit across disciplines and from diverse geographic areas and institutions. From the first cycle, 2007-12, a total of 23 pre-doctoral students participated in the VT IMSD program. A total of 16 (or 69.5%) have completed and received the PhD degree; Total Year 1: $467,489.
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    Ag Commodities - VCE Showcasing Scholarship Poster
    Arnold, Sandy; Baker, Karen (2017-02-22)
    Youth are our future. Agriculture is our lifeline. Extension merges these two vital topics together through the 4-H Agriculture Commodities Tour, bringing awareness of the necessity for both to meet on an intimate real-life, out-of-classroom experience. Despite the continual and increasing demand for educated agriculturalists, interest and enrollment in agricultural fields of study has stagnated or declined. Lack of exposure, experience and familiarity with agricultural opportunities is likely a large contributor to this problem. By connecting across the state with Extension Agriculture State Specialists and Agents at the ARECs as part of the 2016 tour, 28 inner-city youth had the opportunity of a lifetime to explore agricultural lifestyles and potential careers. Providing more than basic agricultural information books can ever provide, these youths explored the importance of sustainability and stewardship across the state through talks, demonstrations and experiential hands-on learning opportunities. In addition, while learning how agriculture relates to their lives, this also gave them an awareness of career opportunities in agriculture that interest them. Studies demonstrate these interventions yield positive in attracting youth considering agricultural fields as viable career options (McCallister, Lee, & Mason, 2005; Shivy & Koehly, 2002; Esters, 2007; Ladany, Melincoff, Constantine, & Love, 1997). Although measuring the outcome of our youth and their future is beyond the scope of this initial investment, it is hoped that this tour has made a significant impact on the youth’s perception of agriculture outside of the classroom, and encourages them to seek further into this new world of possibilities.
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    Allelic variation in rice Fertilization Independent Endosperm 1 contributes to grain width under high night temperature stress
    Dhatt, Balpreet K.; Paul, Puneet; Sandhu, Jaspreet; Hussain, Waseem; Irvin, Larissa; Zhu, Feiyu; Adviento-Borbe, Maria Arlene; Lorence, Argelia; Staswick, Paul; Yu, Hongfeng; Morota, Gota; Walia, Harkamal (2020-10)
    A higher minimum (night-time) temperature is considered a greater limiting factor for reduced rice yield than a similar increase in maximum (daytime) temperature. While the physiological impact of high night temperature (HNT) has been studied, the genetic and molecular basis of HNT stress response remains unexplored. We examined the phenotypic variation for mature grain size (length and width) in a diverse set of rice accessions under HNT stress. Genome-wide association analysis identified several HNT-specific loci regulating grain size as well as loci that are common for optimal and HNT stress conditions. A novel locus contributing to grain width under HNT conditions colocalized withFie1, a component of the FIS-PRC2 complex. Our results suggest that the allelic difference controlling grain width under HNT is a result of differential transcript-level response ofFie1in grains developing under HNT stress. We present evidence to support the role ofFie1in grain size regulation by testing overexpression (OE) and knockout mutants under heat stress. The OE mutants were either unaltered or had a positive impact on mature grain size under HNT, while the knockouts exhibited significant grain size reduction under these conditions.
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    Altered phosphorylation, electrophysiology, and behavior on attenuation of PDE4B action in hippocampus
    Campbell, Susan L.; van Groen, Thomas; Kadish, Inga; Smoot, Lisa High Mitchell; Bolger, Graeme B. (BMC, 2017)
    Background: PDE4 cyclic nucleotide phosphodiesterases regulate 3′, 5′ cAMP abundance in the CNS and thereby regulate PKA activity and phosphorylation of CREB, which has been implicated in learning and memory, depression and other functions. The PDE4 isoform PDE4B1 also interacts with the DISC1 protein, implicated in neural development and behavioral disorders. The cellular functions of PDE4B1 have been investigated extensively, but its function(s) in the intact organism remained unexplored. Results: To specifically disrupt PDE4B1, we developed mice that express a PDE4B1-D564A transgene in the hippocampus and forebrain. The transgenic mice showed enhanced phosphorylation of CREB and ERK1/2 in hippocampus. Hippocampal neurogenesis was increased in the transgenic mice. Hippocampal electrophysiological studies showed increased baseline synaptic transmission and enhanced LTP in male transgenic mice. Behaviorally, male transgenic mice showed increased activity in prolonged open field testing, but neither male nor female transgenic mice showed detectable anxiety-like behavior or antidepressant effects in the elevated plus-maze, tail-suspension or forced-swim tests. Neither sex showed any significant differences in associative fear conditioning or showed any demonstrable abnormalities in pre-pulse inhibition. Conclusions: These data support the use of an isoform-selective approach to the study of PDE4B1 function in the CNS and suggest a probable role of PDE4B1 in synaptic plasticity and behavior. They also provide additional rationale and a refined approach to the development of small-molecule PDE4B1-selective inhibitors, which have potential functions in disorders of cognition, memory, mood and affect.
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    AMP-Activated Protein Kinase Mediates the Effect of Leptin on Avian Autophagy in a Tissue-Specific Manner
    Piekarski, Alissa; Nagarajan, Gurueswar; Ishola, Peter; Flees, Joshua; Greene, Elizabeth S.; Kuenzel, Wayne J.; Ohkubo, Takeshi; Maier, Helena; Bottje, Walter G.; Cline, Mark A.; Dridi, Sami (Frontiers, 2018-05-15)
    Autophagy, a highly conserved intracellular self-digestion process, plays an integral role in maintaining cellular homeostasis. Although emerging evidence indicate that the endocrine system regulates autophagy in mammals, there is still a scarcity of information on autophagy in avian (non-mammalian) species. Here, we show that intracerebroventricular administration of leptin reduces feed intake, modulates the expression of feeding-related hypothalamic neuropeptides, activates leptin receptor and signal transducer and activator of transcription (Ob-Rb/STAT) pathway, and significantly increases the expression of autophagy-related proteins (Atg3, Atg5, Atg7, beclinl, and LC3B) in chicken hypothalamus, liver, and muscle. Similarly, leptin treatment activates Ob-Rb/STAT pathway and increased the expression of autophagy-related markers in chicken hypothalamic organotypic cultures, muscle (QM7) and hepatocyte (Sim-CEL) cell cultures as well as in Chinese Hamster Ovary (CHO-K1) cells-overexpressmg chicken Ob-Rb and STAT3. To define the downstream mediator(s) of leptin's effects on autophagy, we determined the role of the master energy sensor AMP-activated protein kinase (AMPK). Leptin treatment significantly increased the phosphorylated levels of AMPK alpha 1/2 at Thr172 site in chicken hypothalamus and liver, but not in muscle. Likewise, AMPK alpha 1/2 was activated by leptin in chicken hypothalamic organotypic culture and Sim-CEL, but not in QM7 cells. Blocking AMPK activity by compound C reverses the autophagy-inducing effect of leptin. Together, these findings indicate that AMPK mediates the effect of leptin on chicken autophagy in a tissue-specific manner.
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    Animal welfare assessment of on-farm euthanasia methods for individual, heavy turkeys
    Jacobs, Leonie; Bourassa, Dianna V.; Boyal, Ranjit S.; Harris, Caitlin E.; Josselson, L. Nicole Bartenfeld; Campbell, Andrew M.; Anderson, Gracie; Buhr, R. Jeff (2021-03)
    On-farm euthanasia of poultry, including turkeys, may not be possible for most people as birds gain weight; thus alternative mechanical methods have been developed. Our objective was to compare mechanical cervical dislocation with the Koechner Euthanizing Device (KED), captive bolt euthanasia with the Turkey Euthanasia Device (TED), head-only CO2 euthanasia (CO2), and electric euthanasia as potential humane methods for euthanizing individual, heavy turkeys. We assessed their impact on loss of brain stem reflexes, acute distress (corticosterone, CORT), kill success, torn skin, and blood loss. Turkeys (n 5 174) were euthanized on 3 sampling days, while birds were restrained using a mobile bird euthanasia apparatus. Brain stem reflexes recorded were the cessation and return of induced nictitating membrane reflex (loss of consciousness and brain stem dysfunction), mouth gaping reflex (brain stem dysfunction), and musculoskeletal movements (spinal cord dysfunction). Overall, KED resulted in more frequent (at 4 min: KED 7 of 14; electric 0 of 13; TED 0 of 11; CO2 2 of 14 birds on day 1) and longer durations of the induced nictitating reflex compared to the other methods (means of day 2 and 3: KED 233; electric 15; TED 15; CO2 15 s). The mouth gaping reflex endured the longest after KED euthanasia (means of day 2 and 3: KED 197; electric 15; TED 51; CO2 15 s). Musculoskeletal movements endured longest after KED euthanasia (means of day 2 and 3: KED 235; electric 15; TED 219; CO2 15 s). Returning reflexes were more frequent after KED and TED compared to CO2 and electric euthanasia, where it was absent. CO2, electric, and TED euthanasia showed comparable kill success (success: CO2 42 out of 43; electric 44 of 45; TED 42 of 44), with KED resulting in most unsuccessful kills (unsuccessful: 8 out of 42). CORT responses were inconsistent. Torn skin and blood loss occurred more frequently after KED and TED compared to CO2 and electric applications. Therefore, we conclude that, based on a comparison of these 4 methods, the most discernibly humane was electric euthanasia, which consistently resulted in quick loss of consciousness within 15 s, no returning reflexes, and no torn skin or blood loss.
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    APSC Newsletter, Fall 2012
    (Virginia Tech, 2012)
    Published twice a year, this newsletter details student, faculty, and staff accomplishments and activities in the Department of Animal and Poultry Sciences at Virginia Tech.
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    APSC Newsletter, Fall/Winter 2013
    (Virginia Tech, 2013)
    Published twice a year, this newsletter details student, faculty, and staff accomplishments and activities in the Department of Animal and Poultry Sciences at Virginia Tech.
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    APSC Newsletter, Fall/Winter 2014
    (Virginia Tech, 2014)
    Published twice a year, this newsletter details student, faculty, and staff accomplishments and activities in the Department of Animal and Poultry Sciences at Virginia Tech.
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    APSC Newsletter, Spring/Summer 2012
    (Virginia Tech, 2012)
    Published twice a year, this newsletter details student, faculty, and staff accomplishments and activities in the Department of Animal and Poultry Sciences at Virginia Tech.
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    APSC Newsletter, Spring/Summer 2013
    (Virginia Tech, 2013)
    Published twice a year, this newsletter details student, faculty, and staff accomplishments and activities in the Department of Animal and Poultry Sciences at Virginia Tech.
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    APSC Newsletter, Spring/Summer 2014
    (Virginia Tech, 2014)
    Published twice a year, this newsletter details student, faculty, and staff accomplishments and activities in the Department of Animal and Poultry Sciences at Virginia Tech.
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    APSC Newsletter, Spring/Summer 2015
    (Virginia Tech, 2015)
    Published twice a year, this newsletter details student, faculty, and staff accomplishments and activities in the Department of Animal and Poultry Sciences at Virginia Tech.
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    ASAS-NANP SYMPOSIUM: prospects for interactive and dynamic graphics in the era of data-rich animal science
    Morota, Gota; Cheng, Hao; Cook, Dianne; Tanaka, Emi (2021-02)
    Statistical graphics, and data visualization, play an essential but under-utilized, role for data analysis in animal science, and also to visually illustrate the concepts, ideas, or outputs of research and in curricula. The recent rise in web technologies and ubiquitous availability of web browsers enables easier sharing of interactive and dynamic graphics. Interactivity and dynamic feedback enhance humancomputer interaction and data exploration. Web applications such as decision support systems coupled with multimedia tools synergize with interactive and dynamic graphics. However, the importance of graphics for effectively communicating data, understanding data uncertainty, and the state of the field of interactive and dynamic graphics is underappreciated in animal science. To address this gap, we describe the current state of graphical methodology and technology that might be more broadly adopted. This includes an explanation of a conceptual framework for effective graphics construction. The ideas and technology are illustrated using publicly available animal datasets. We foresee that many new types of big and complex data being generated in precision livestock farming create exciting opportunities for applying interactive and dynamic graphics to improve data analysis and make data-supported decisions.
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    An assessment of genomic connectedness measures in Nellore cattle
    Amorim, Sabrina T.; Yu, Haipeng; Momen, Mehdi; de Albuquerque, Lucia Galvao; Cravo Pereira, Angelica S.; Baldi, Fernando; Morota, Gota (2020-11)
    An important criterion to consider in genetic evaluations is the extent of genetic connectedness across management units (MU), especially if they differ in their genetic mean. Reliable comparisons of genetic values across MU depend on the degree of connectedness: the higher the connectedness, the more reliable the comparison. Traditionally, genetic connectedness was calculated through pedigree-based methods; however, in the era of genomic selection, this can be better estimated utilizing new approaches based on genomics. Most procedures consider only additive genetic effects, which may not accurately reflect the underlying gene action of the evaluated trait, and little is known about the impact of non-additive gene action on connectedness measures. The objective of this study was to investigate the extent of genomic connectedness measures, for the first time, in Brazilian field data by applying additive and non-additive relationship matrices using a fatty acid profile data set from seven farms located in the three regions of Brazil, which are part of the three breeding programs. Myristic acid (C14:0) was used due to its importance for human health and reported presence of non-additive gene action. The pedigree included 427,740 animals and 925 of them were genotyped using the Bovine high-density genotyping chip. Six relationship matrices were constructed, parametrically and non-parametrically capturing additive and non-additive genetic effects from both pedigree and genomic data. We assessed genome-based connectedness across MU using the prediction error variance of difference (PEVD) and the coefficient of determination (CD). PEVD values ranged from 0.540 to 1.707, and CD from 0.146 to 0.456. Genomic information consistently enhanced the measures of connectedness compared to the numerator relationship matrix by at least 63%. Combining additive and non-additive genomic kernel relationship matrices or a non-parametric relationship matrix increased the capture of connectedness. Overall, the Gaussian kernel yielded the largest measure of connectedness. Our findings showed that connectedness metrics can be extended to incorporate genomic information and non-additive genetic variation using field data. We propose that different genomic relationship matrices can be designed to capture additive and non-additive genetic effects, increase the measures of connectedness, and to more accurately estimate the true state of connectedness in herds.
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    Association between FAMACHA scores and fecal egg counts in Katahdin lambs
    Notter, David R.; Burke, Joan M.; Miller, James E.; Morgan, James L. M. (2017-03)
    The FAMACHA system was introduced to the U.S. just over 10 yr ago to allow selective deworming of lambs with anemia associated with Haemonchus contortus and retard the development of anthelmintic resistance. The FAMACHA system was initially developed as a predictor of packed cell volume (PCV), but correlations between FAMACHA and fecal egg counts (FEC) have also been reported. It is important to understand factors that influence FAMACHA scores among farms to improve management of gastrointestinal nematodes. The objectives of this study were therefore to quantify associations between FAMACHA scores, FEC, BW, and age in Katahdin lambs at 2 different measurement times in 8 flocks in the eastern U.S., and to assess consistency of relationships between FAMACHA and FEC among flocks. Data came from 1,644 Katahdin lambs from 7 flocks sampled at approximately 90 d of age, and 1,295 lambs from 6 flocks sampled at approximately 120 d of age over a 5 yr period. Residual correlations among log-transformed FEC (LFEC), FAMACHA scores, BW, and lamb ages at each measurement time were determined. Repeatability of each variable was also determined as residual correlations among repeated measures. At both 90 and 120 d of age, correlations of FAMACHA scores with LFEC and BW were significant (P < 0.001), but numerically modest (0.25 and -0.16, respectively at 90 d; 0.31 and -0.16, respectively at 120 d), demonstrating that higher FAMACHA scores were associated with higher FEC and more likely to be observed in lighter lambs. A small negative correlation was observed between FAMACHA score and lamb age (r = -0.05, P = 0.05, 90 d; r = -0.11, P < 0.001, 120 d) indicating that younger lambs were more likely to have elevated FAMACHA scores. Thus, younger and lighter lambs will likely be more susceptible to parasitism and may need to be managed more diligently than older or heavier lambs. In addition, FAMACHA scores have potential to improve breeding value estimates in programs designed to genetically improve parasite resistance.