10 research outputs found
Effects of Genetic Selection for Residual Feed Intake on Behavioral Reactivity of Castrated Male Pigs to Novel Stimuli Tests
Increasing feed efficiency in swine is important for increasing sustainable food production and profitability for producers; therefore, this is often selected for at breeding. Residual feed intake (RFI) can be used for the genetic selection of pigs for feed efficiency. In our selection project, low-RFI pigs consume less feed for equal weight gain compared to their less efficient, high-RFI counterparts. However, little is known about how feed efficiency influences the pig\u27s behavioral reactivity toward fear-eliciting stimuli. In this study, behavioral reactivity of pigs divergently selected for RFI was evaluated using human approach- (HAT) and novel object tests (NOT). Forty low-RFI (more feed efficient) and 40 high-RFI (less feed efficient) castrated male pigs (barrows; 46.5 ± 8.6 kg) from 8th generation Yorkshire RFI selection lines were randomly selected and evaluated once using HAT and once using NOT over a four week period utilizing a crossover experimental design. Each pig was individually tested within a 4.9 × 2.4 m test arena for 10 min; behavior was evaluated using live and video observations. The test arena floor was divided into four zones; zone 1 being oral, nasal, and/or facial contact with the human (HAT) or orange traffic cone (NOT) and zone 4 being furthest from the human or cone and included the point where the pig entered the arena. During both HAT and NOT, low-RFI pigs crossed fewer zones (P \u3c 0.0001), had fewer head movements (P ≤ 0.02), defecated less frequently (P ≤ 0.03), displayed a shorter duration of freezing (P = 0.05), and froze less frequently (HAT: low-RFI = 4.9 ± 0.65 vs. high-RFI = 7.5 ± 0.96; NOT: low-RFI = 4.7 ± 0.66 vs. high-RFI = 7.2 ± 0.96; P \u3c 0.0001) compared to high-RFI pigs. During HAT, low-RFI pigs also attempted to escape less frequently (low-RFI = 0.4 ± 0.14 vs. high-RFI = 1.1 ± 0.30; P = 0.001) compared to high-RFI pigs. In contrast, compared to the high-RFI pigs, low-RFI pigs took 48 s longer during HAT and 52 s longer during NOT to approach zone 1 (P ≤ 0.04). These results indicate that low-RFI pigs had decreased behavioral reactivity during HAT and NOT compared to high-RFI pigs. This may suggest that reducing a pig\u27s behavioral reactivity is an important component of improving feed efficiency; however, it may have implications for animal handling and facility design
Review: Assessment of completeness of reporting in intervention studies using livestock: an example from pain mitigation interventions in neonatal piglets
Accurate and complete reporting of study methods, results and interpretation are essential components for any scientific process, allowing end-users to evaluate the internal and external validity of a study. When animals are used in research, excellence in reporting is expected as a matter of continued ethical acceptability of animal use in the sciences. Our primary objective was to assess completeness of reporting for a series of studies relevant to mitigation of pain in neonatal piglets undergoing routine management procedures. Our second objective was to illustrate how authors can report the items in the Reporting guidElines For randomized controLled trials for livEstoCk and food safety (REFLECT) statement using examples from the animal welfare science literature. A total of 52 studies from 40 articles were evaluated using a modified REFLECT statement. No single study reported all REFLECT checklist items. Seven studies reported specific objectives with testable hypotheses. Six studies identified primary or secondary outcomes. Randomization and blinding were considered to be partially reported in 21 and 18 studies, respectively. No studies reported the rationale for sample sizes. Several studies failed to report key design features such as units for measurement, means, standard deviations, standard errors for continuous outcomes or comparative characteristics for categorical outcomes expressed as either rates or proportions. In the discipline of animal welfare science, authors, reviewers and editors are encouraged to use available reporting guidelines to ensure that scientific methods and results are adequately described and free of misrepresentations and inaccuracies. Complete and accurate reporting increases the ability to apply the results of studies to the decision-making process and prevent wastage of financial and animal resources
Quantitative 18F-AV1451 Brain Tau PET Imaging in Cognitively Normal Older Adults, Mild Cognitive Impairment, and Alzheimer's Disease Patients
Recent developments of tau Positron Emission Tomography (PET) allows assessment of regional neurofibrillary tangles (NFTs) deposition in human brain. Among the tau PET molecular probes, 18F-AV1451 is characterized by high selectivity for pathologic tau aggregates over amyloid plaques, limited non-specific binding in white and gray matter, and confined off-target binding. The objectives of the study are (1) to quantitatively characterize regional brain tau deposition measured by 18F-AV1451 PET in cognitively normal older adults (CN), mild cognitive impairment (MCI), and AD participants; (2) to evaluate the correlations between cerebrospinal fluid (CSF) biomarkers or Mini-Mental State Examination (MMSE) and 18F-AV1451 PET standardized uptake value ratio (SUVR); and (3) to evaluate the partial volume effects on 18F-AV1451 brain uptake.Methods: The study included total 115 participants (CN = 49, MCI = 58, and AD = 8) from the Alzheimer's Disease Neuroimaging Initiative (ADNI). Preprocessed 18F-AV1451 PET images, structural MRIs, and demographic and clinical assessments were downloaded from the ADNI database. A reblurred Van Cittertiteration method was used for voxelwise partial volume correction (PVC) on PET images. Structural MRIs were used for PET spatial normalization and region of interest (ROI) definition in standard space. The parametric images of 18F-AV1451 SUVR relative to cerebellum were calculated. The ROI SUVR measurements from PVC and non-PVC SUVR images were compared. The correlation between ROI 18F-AV1451 SUVR and the measurements of MMSE, CSF total tau (t-tau), and phosphorylated tau (p-tau) were also assessed.Results:18F-AV1451 prominently specific binding was found in the amygdala, entorhinal cortex, parahippocampus, fusiform, posterior cingulate, temporal, parietal, and frontal brain regions. Most regional SUVRs showed significantly higher uptake of 18F-AV1451 in AD than MCI and CN participants. SUVRs of small regions like amygdala, entorhinal cortex and parahippocampus were statistically improved by PVC in all groups (p < 0.01). Although there was an increasing tendency of 18F-AV-1451 SUVRs in MCI group compared with CN group, no significant difference of 18F-AV1451 deposition was found between CN and MCI brains with or without PVC (p > 0.05). Declined MMSE score was observed with increasing 18F-AV1451 binding in amygdala, entorhinal cortex, parahippocampus, and fusiform. CSF p-tau was positively correlated with 18F-AV1451 deposition. PVC improved the results of 18F-AV-1451 tau deposition and correlation studies in small brain regions.Conclusion: The typical deposition of 18F-AV1451 tau PET imaging in AD brain was found in amygdala, entorhinal cortex, fusiform and parahippocampus, and these regions were strongly associated with cognitive impairment and CSF biomarkers. Although more deposition was observed in MCI group, the 18F-AV-1451 PET imaging could not differentiate the MCI patients from CN population. More tau deposition related to decreased MMSE score and increased level of CSF p-tau, especially in ROIs of amygdala, entorhinal cortex and parahippocampus. PVC did improve the results of tau deposition and correlation studies in small brain regions and suggest to be routinely used in 18F-AV1451 tau PET quantification
Finishing Steers in a Deep-Bedded Hoop Barn and a Conventional Feedlot: Effects on Behavior and Temperament in Iowa
As the Iowa beef industry invests in environmental management, there has been increasing interest in systems that minimize runoff. One example of such a facility is the deep-bedded hoop barn. To date there is limited information comparing animals raised for beef production in regards to their behavior between the deep-bedded hoop barns and other housing systems for beef cattle. Identifying potential alterations in cattle behavior and overall temperament between different housing systems can help producers when redesigning facilities and in the creation of educational management tools, to maximize beneficial impacts for animal well-being and economical return. The objective of this study was to compare steer behavior and temperament between two housing treatments; hoop building (HP) vs. conventional feedlot (FD).</p
Beef Cattle Feeding in a Bedded Hoop Barn: Three Year Summary
Iowa’s beef cattle industry is comprehensively evaluating the environmental management of feedlots. As the Iowa cattle feeding industry focuses on environmental management, there has been increasing interest in systems where runoff is minimized, such as a bedded hoop barn. A three-year study evaluating the performance of yearling steers in a bedded hoop barn was conducted.</p
Effects of Genetic Selection for Residual Feed Intake on Behavioral Reactivity of Castrated Male Pigs to Novel Stimuli Tests
Increasing feed efficiency in swine is important for increasing sustainable food production and profitability for producers; therefore, this is often selected for at breeding. Residual feed intake (RFI) can be used for the genetic selection of pigs for feed efficiency. In our selection project, low-RFI pigs consume less feed for equal weight gain compared to their less efficient, high-RFI counterparts. However, little is known about how feed efficiency influences the pig's behavioral reactivity toward fear-eliciting stimuli. In this study, behavioral reactivity of pigs divergently selected for RFI was evaluated using human approach- (HAT) and novel object tests (NOT). Forty low-RFI (more feed efficient) and 40 high-RFI (less feed efficient) castrated male pigs (barrows; 46.5 ± 8.6 kg) from 8th generation Yorkshire RFI selection lines were randomly selected and evaluated once using HAT and once using NOT over a four week period utilizing a crossover experimental design. Each pig was individually tested within a 4.9 × 2.4 m test arena for 10 min; behavior was evaluated using live and video observations. The test arena floor was divided into four zones; zone 1 being oral, nasal, and/or facial contact with the human (HAT) or orange traffic cone (NOT) and zone 4 being furthest from the human or cone and included the point where the pig entered the arena. During both HAT and NOT, low-RFI pigs crossed fewer zones (P P ≤ 0.02), defecated less frequently (P ≤ 0.03), displayed a shorter duration of freezing (P = 0.05), and froze less frequently (HAT: low-RFI = 4.9 ± 0.65 vs. high-RFI = 7.5 ± 0.96; NOT: low-RFI = 4.7 ± 0.66 vs. high-RFI = 7.2 ± 0.96; P P = 0.001) compared to high-RFI pigs. In contrast, compared to the high-RFI pigs, low-RFI pigs took 48 s longer during HAT and 52 s longer during NOT to approach zone 1 (P ≤ 0.04). These results indicate that low-RFI pigs had decreased behavioral reactivity during HAT and NOT compared to high-RFI pigs. This may suggest that reducing a pig's behavioral reactivity is an important component of improving feed efficiency; however, it may have implications for animal handling and facility design.This is the author’s version of a work that was accepted for publication in Applied Animal Behaviour Science. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. Changes may have been made to this work since it was submitted for publication. A definitive version was subsequently published in Applied Animal Behaviour Science, 159 (October 2014)] DOI#10.1016/j.applanim.2014.06.013.</p
Genetic parameters for growth, body composition, and structural soundness traits in commercial gilts
The objective of this study was to estimate genetic parameters for growth, body composition, and structural soundness traits in commercial gilt lines. The data included 1,449 gilts: 462 females from a grandparent maternal line and 987 from a parent maternal line. Growth was expressed as number of days to a constant 113.5 kg BW (DAYS) and compositional traits included loin muscle area (LMA), 10th rib backfat (BF10), and last rib backfat (LRF). Subjective structural soundness evaluation was completed using a 9-point scale and included: body length (BL), body depth (BD), body width (BWD), rib shape (BRS), top line (BTL), and hip structure (BHS); front legs: legs turned (FLT), buck knees (FBK), pastern posture (FPP), foot size (FFS), and uneven toes (FUT); rear legs: legs turned (RLT), leg posture (RLP), pastern posture (RPP), foot size (RFS), and uneven toes (RUT); and overall leg action (OLA). Genetic parameters were estimated with multivariate linear animal models, using the average information REML algorithm. Heritability estimates for growth and body composition traits ranged from 0.50 to 0.70, for body structure traits from 0.15 to 0.31, for leg structure traits from 0.07 to 0.31, and the estimate for OLA was 0.12. Several moderate to high genetic correlations were obtained among body structure traits, whereas correlations among leg structure traits were mainly low and nonsignificant. A strong correlation was found between FPP and OLA (P P This is an article from Journal of Animal Science 91 (2013): 2034, doi:10.2527/jas.2012-5722. Posted with permission.</p
Review: Assessment of completeness of reporting in intervention studies using livestock: an example from pain mitigation interventions in neonatal piglets
Accurate and complete reporting of study methods, results and interpretation are essential components for any scientific process, allowing end-users to evaluate the internal and external validity of a study. When animals are used in research, excellence in reporting is expected as a matter of continued ethical acceptability of animal use in the sciences. Our primary objective was to assess completeness of reporting for a series of studies relevant to mitigation of pain in neonatal piglets undergoing routine management procedures. Our second objective was to illustrate how authors can report the items in the Reporting guidElines For randomized controLled trials for livEstoCk and food safety (REFLECT) statement using examples from the animal welfare science literature. A total of 52 studies from 40 articles were evaluated using a modified REFLECT statement. No single study reported all REFLECT checklist items. Seven studies reported specific objectives with testable hypotheses. Six studies identified primary or secondary outcomes. Randomization and blinding were considered to be partially reported in 21 and 18 studies, respectively. No studies reported the rationale for sample sizes. Several studies failed to report key design features such as units for measurement, means, standard deviations, standard errors for continuous outcomes or comparative characteristics for categorical outcomes expressed as either rates or proportions. In the discipline of animal welfare science, authors, reviewers and editors are encouraged to use available reporting guidelines to ensure that scientific methods and results are adequately described and free of misrepresentations and inaccuracies. Complete and accurate reporting increases the ability to apply the results of studies to the decision-making process and prevent wastage of financial and animal resources.This article is published as O’Connor, Annette, Raymond Anthony, Luciana Bergamasco, J. F. Coetzee, R. S. Dzikamunhenga, A. K. Johnson, L. A. Karriker et al. "Assessment of completeness of reporting in intervention studies using livestock: an example from pain mitigation interventions in neonatal piglets." animal 10, no. 4 (2016): 660-670. Doi: 10.1017/S1751731115002323. Posted with permission.</p