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1.
Gerontol Geriatr Educ ; 44(3): 429-448, 2023 07 03.
Artigo em Inglês | MEDLINE | ID: mdl-35758104

RESUMO

Interdisciplinary education and research foster cross disciplinary collaboration. The study of age and aging is complex and needs to be carried out by scholars from myriad disciplines, making interdisciplinary collaboration paramount. Non-formal, extracurricular, and interdisciplinary networks are increasingly filling gaps in academia's largely siloed disciplinary training. This study examines the experiences of trainees (undergraduate, graduate, and post-graduate students) who belonged to one such network devoted to interdisciplinary approaches to education and research on aging. Fifty-three trainees completed the survey. Among respondents, some faculties (e.g., Health Sciences) were disproportionately represented over others (e.g., Business, Engineering, and Humanities). Most trainees valued their participation in the interdisciplinary network for research on aging. They also valued expanding their social and professional network, the nature of which was qualitatively described in open-text responses. We then relate our findings to three types of social capital: bonding; bridging; and linking. Finally, we conclude with recommendations for the intentional design and/or refinement of similar networks to maximize value to trainees, provide the skills necessary for interdisciplinary collaboration, and foster egalitarian and representative participation therein.


Assuntos
Geriatria , Humanos , Geriatria/educação , Estudos Interdisciplinares , Ciências Humanas , Envelhecimento
2.
Gerontol Geriatr Educ ; 38(1): 17-46, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-27635670

RESUMO

As the number of older adults increases, it is imperative that gerontological competencies are imbedded in health and social service education reviews of Canadian published and grey literature presents trends, barriers, and enablers of sustained movement toward graduating professionals with gerontology competencies. Overall, gerontological education remains insufficient. Main barriers include resources for faculty and teaching. This review also identified discipline-specific competency frameworks that could inform curriculum enhancement and education accreditations; however, most educators were unaware of these. Further limiting workforce development is the lack of gerontology competency statements within regulatory documents. This review concludes with recommendations for federal and provincial policies to establish educational accreditation programs in geriatrics, develop core competencies, and integrate these into regulatory frameworks. Failure to do so will continue the trend of insufficient preparation of health and social service professionals to care for older adults.


Assuntos
Geriatria/educação , Pessoal de Saúde/educação , Serviço Social/educação , Canadá , Currículo , Geriatria/economia , Humanos , Relações Interprofissionais , Políticas , Competência Profissional
3.
Can J Aging ; : 1-7, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38679950

RESUMO

Visual representations of aging have historically relied upon binarized clichés: idealized youthfulness versus frailty and illness. To challenge these oversimplified depictions, graduate students developed a community outreach project titled 'Seniors of Canada'. The aim of this project was twofold: (1) share images and stories of people in later life; and (2) challenge dominant narratives and stereotypes of aging. In this note, we outline the prevailing discourse of what aging 'looks like', how we collected stories and images, and implications for knowledge mobilization and research in Canada. This article highlights insights gained since the inception of the project, including three key learnings: (1) Building bridges across academia and community, (2) Intergenerational connection and digital tools, and (3) The power of visual storytelling. We provide a practical overview of a successful knowledge mobilization/community outreach project and showcase the power of bridging academia and community for social change.

4.
J Anim Sci ; 1022024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-39051136

RESUMO

This experiment evaluated the performance, health, and physiological responses of high-risk steers receiving a Bacillus-based probiotic during a 90-d grazing period. A total of 240 Angus-influenced steers were used in this experiment that was replicated over 2 yr (120 steers/year). Each year, steers were obtained from an auction yard and transported to the experimental facility (120 km). Steer body weight (BW) was recorded at arrival (day -1), and this value was averaged with BW recorded on day 0 to represent the initial BW (236.6 ± 1.5 kg). On day 0, steers were ranked by BW and allocated to 1 of 12 pastures with stockpiled native grass (4-ha pastures; 10 steers/pasture). Pastures were randomly assigned to receive daily supplementation with dried distillers' grains at 1% of BW containing either: 1) Bacillus subtilis + B. licheniformis probiotic (BOV; 2 g/steer daily of Bovacillus; Novonesis, Horsholm, Denmark) or 2) no feed additive (CON). Cattle received treatments from days 0 to 90, in addition to free-choice access to water and mineral + vitamin mix without ionophore. Steers were assessed for bovine respiratory disease (BRD) signs daily. Blood samples were collected and full BW was recorded on days 0, 14, 28, 56, and 90. Shrunk BW was recorded on day 91 after 16 h of feed and water restriction, and a 4% pencil shrink was used to calculate the final BW. Average daily gain (ADG) was calculated based on initial and final BW. No treatment effects were detected (P ≥ 0.73) for steer final BW and ADG. A treatment × day interaction was detected (P ≤ 0.05) for plasma haptoglobin concentration, which was greater for CON steers on days 14 and 28 (P ≤ 0.02). Incidence of BRD signs did not differ (P = 0.97) between treatments (51.7% and 51.3% for BOV and CON, respectively; SEM = 7.70). However, steer mortality + removals for health complications were greater (P = 0.01) in CON compared to BOV (0.00% vs. 5.04%, respectively; SEM = 1.41). Supplementing BOV improved (P ≤ 0.04) total pasture-based liveweight change (643 vs. 502 kg/pasture, respectively; SEM = 45) and final pasture-based total liveweight (3,007 vs. 2,869 kg/pasture, respectively; SEM = 46). Collectively, supplementation with a probiotic based on B. subtilis and B. licheniformis to high-risk stocker cattle did not alleviate the incidence of BRD signs nor improved ADG, but decreased acute-phase protein response, reduced steer mortality + removal, and increased pasture-based productivity during a 90-d grazing period.


Stocker cattle are exposed to several stressors within a short period of time, which impair their immunity and lead to bovine respiratory disease (BRD). With the increased regulations regarding the use of antimicrobials in cattle nutrition, novel dietary strategies to improve health and productivity of stocker cattle are warranted. One example is supplementing Bacillus-based probiotics, which promote performance and immunity in high-stress cattle. In this study, steers were purchased from a commercial auction yard soon after weaning, transported to the research facility, and assigned initial processing within a 48-h period. Steers were assigned to pastures and were supplemented or not with the Bacillus-based probiotic during a 90-d grazing period. In general, supplementing steers with the Bacillus-based probiotic did not impact growth rates or BRD incidence. However, no steers that received the Bacillus-based probiotic died from BRD consequences nor were removed from the experiment due to health reasons, whereas 5% of unsupplemented steers did not complete the 90-d experiment. Consequently, pasture-based liveweight gain was increased by 28% due to Bacillus-based probiotic supplementation. Results from this study indicate that supplementing a B. subtilis + B. licheniformis probiotic could be an alternative to improve the health and overall productivity of high-risk stocker cattle.


Assuntos
Ração Animal , Dieta , Probióticos , Animais , Bovinos/fisiologia , Probióticos/farmacologia , Probióticos/administração & dosagem , Masculino , Ração Animal/análise , Dieta/veterinária , Bacillus licheniformis , Suplementos Nutricionais , Bacillus subtilis , Distribuição Aleatória , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/prevenção & controle , Aumento de Peso
5.
Animals (Basel) ; 14(15)2024 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-39123712

RESUMO

Supplementing trace minerals is common in managing bovine respiratory disease (BRD) in post-weaned cattle; however, its influence on host immunity and metabolism in high-risk cattle remains unclear. We aimed to assess the impact of three supplementation programs on liver and serum trace element concentrations and blood gene expression. Fifty-six high-risk beef steers were randomly assigned to one of three groups over 60 days: (1) sulfate-sourced Cu, Co, Mn, and Zn (INR), (2) amino acid-complexed Cu, Mn, Co, and Zn (AAC), or (3) AAC plus trace mineral and vitamin drench (COMBO). Serum and liver biopsies for Cu, Co, Mn, and Zn at d0, d28, and d60 were analyzed from cattle free of BRD (n = 9 INR; n = 6 AAC; n = 10 COMBO). Differences and correlations of mineral concentrations were analyzed via generalized linear mixed models and Spearman's rank coefficients, respectively (p < 0.05). Whole blood RNA samples from healthy cattle (n = 4 INR; n = 4 AAC; n = 4 COMBO) at d0, d13, d28, d45, and d60 were sequenced and analyzed for differentially expressed genes (DEGs) via glmmSeq (FDR < 0.05), edgeR (FDR < 0.10), and Trendy (p < 0.10). Serum and liver Cu and Co concentrations increased over time in all groups, with higher liver Cu in COMBO (487.985 µg/g) versus AAC (392.043 µg/g) at d60 (p = 0.013). Serum and liver Cu concentrations (ρ = 0.579, p = 6.59 × 10-8) and serum and liver Co concentrations (ρ = 0.466, p = 2.80 × 10-5) were linearly correlated. Minimal gene expression differences were found between AAC versus COMBO (n = 2 DEGs) and INR versus COMBO (n = 0 DEGs) over time. AAC versus INR revealed 107 DEGs (d13-d60) with increased traits in AAC including metabolism of carbohydrates/fat-soluble vitamins, antigen presentation, ATPase activity, and B- and T-cell activation, while osteoclast differentiation and neutrophil degranulation decreased in AAC compared to INR. Our study identifies gene expression differences in high-risk cattle fed inorganic or amino acid-complexed mineral supplements, revealing adaptive immune and metabolic mechanisms that may be improved by organically sourced supplementation.

6.
J Anim Sci ; 1022024 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-38820137

RESUMO

This experiment evaluated growth, physiological responses, and puberty attainment in beef heifers reared in drylots with a high stocking density, and provided or not with a moderate exercise regimen. A total of 180 heifers (75% Angus × 25% Brahman) were used in this experiment replicated over 2 yr. Each year, 90 heifers were ranked by age (264 ±â€…1 d) and body weight (BW on day -3; 200 ±â€…2 kg) on day 0, and assigned to a) one of six drylot pens (10 × 14 m pens; 10 heifers per pen) with a stocking density of 14 m2/heifer (DENS), or b) one of three pastures (2-ha pastures; 10 heifers per pasture) with a stocking density of 2,000 m2/heifer (CON). Beginning on day 15, three DENS pens were given access to an exercise area (DENS-EX) 3 times/wk (1 h). Negligible forage was available for CON, whereas heifers from all treatments received the same limit-fed diet (~13 kg/heifer daily). Shrunk BW was recorded after 16 h of feed and water withdrawal on days -3 and 225 to calculate BW gain. Temperament was evaluated on days 0, 128, and 224. Heifers were fitted with a pedometer behind their shoulder on day 0 to record physical activity. Pedometer results and blood samples were collected weekly for progesterone analysis. Hair samples from the tail switch were collected every 28 d. Data were analyzed with pen or pasture as an experimental unit, via ANOVA using the MIXED or GLIMMIX procedures of SAS (SAS Inst. Inc., Cary, NC). Heifers from CON had more (P < 0.01) steps per week compared with DENS and DENS-EX (23,973, 6,706, and 12,354 steps/wk, respectively; SEM = 1,247), and DENS-EX heifers had more (P < 0.01) steps per week compared with DENS. No treatment effects (P ≥ 0.91) were detected for heifer BW gain (~0.820 kg/d). Hair cortisol concentrations were greater (P ≤ 0.05) in DENS and DENS-EX compared with CON beginning on day 56. Exit velocity and temperament score were greater (P ≤ 0.05) in DENS compared with DENS-EX and CON on day 224. Puberty attainment was delayed (treatment × day; P < 0.01) in DENS compared with DENS-EX and CON. A greater (P ≤ 0.05) proportion of CON were pubertal by day 105 compared with DENS and DENS-EX (30.0%, 11.6%, and 15.0%, respectively; SEM = 6.5), while a greater (P < 0.05) proportion of CON and DENS-EX were pubertal by day 154 compared to DENS (61.7%, 66.7%, and 43.3%, respectively; SEM = 6.5). Rearing replacement heifers in drylots with high stocking density has detrimental effects on their puberty attainment, and the moderate exercise regimen partially alleviated this negative outcome.


Replacement beef heifers are often reared in drylots with high stocking density to facilitate feeding and management, or to intensify beef production as availability of grazing areas becomes limited. Studies from our group, however, demonstrated that drylot heifers experience delayed puberty attainment compared with heifers reared on pastures. This negative outcome was associated with chronic stress caused by confinement and restricted physical activity; the latter being a key animal welfare factor with direct effects on reproductive development. Based on this rationale, this experiment evaluated growth, stress-related physiological responses, and puberty attainment heifers reared in drylots and exposed or not to a moderate exercise regimen. Moreover, drylot heifers were compared to contemporary cohorts being reared on pasture. As expected, heifers reared in drylots experienced heightened stress-related physiological responses and delayed puberty attainment compared to pasture heifers. Exposing drylot heifers to the moderate exercise regimen did not alleviate the physiological consequences of chronic stress, but lessened the delay in puberty attainment compared with non-exercised drylot cohorts. Therefore, stocking density and exercise opportunities should be considered to improve heifer welfare and reproductive development in intensive drylot systems, as lack of exercise directly contributes to delayed reproductive development of drylot heifers.


Assuntos
Condicionamento Físico Animal , Maturidade Sexual , Animais , Bovinos/fisiologia , Bovinos/crescimento & desenvolvimento , Feminino , Criação de Animais Domésticos/métodos , Abrigo para Animais , Densidade Demográfica , Progesterona/sangue , Hidrocortisona/sangue
7.
Vet Sci ; 10(3)2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36977250

RESUMO

Bovine respiratory disease (BRD) remains the leading disease within the U.S. beef cattle industry. Marketing decisions made prior to backgrounding may shift BRD incidence into a different phase of production, and the importance of host gene expression on BRD incidence as it relates to marketing strategy is poorly understood. Our objective was to compare the influence of marketing on host transcriptomes measured on arrival at a backgrounding facility on the subsequent probability of being treated for BRD during a 45-day backgrounding phase. This study, through RNA-Seq analysis of blood samples collected on arrival, evaluated gene expression differences between cattle which experienced a commercial auction setting (AUCTION) versus cattle directly shipped to backgrounding from the cow-calf phase (DIRECT); further analyses were conducted to determine differentially expressed genes (DEGs) between cattle which remained clinically healthy during backgrounding (HEALTHY) versus those that required treatment for clinical BRD within 45 days of arrival (BRD). A profound difference in DEGs (n = 2961) was identified between AUCTION cattle compared to DIRECT cattle, regardless of BRD development; these DEGs encoded for proteins involved in antiviral defense (increased in AUCTION), cell growth regulation (decreased in AUCTION), and inflammatory mediation (decreased in AUCTION). Nine and four DEGs were identified between BRD and HEALTHY cohorts in the AUCTION and DIRECT groups, respectively; DEGs between disease cohorts in the AUCTION group encoded for proteins involved in collagen synthesis and platelet aggregation (increased in HEALTHY). Our work demonstrates the clear influence marketing has on host expression and identified genes and mechanisms which may predict BRD risk.

8.
Front Vet Sci ; 9: 1010039, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36225796

RESUMO

The impact of preweaning vaccination for bovine respiratory viruses on cattle health and subsequent bovine respiratory disease morbidity has been widely studied yet questions remain regarding the impact of these vaccines on host response and gene expression. Six randomly selected calves were vaccinated twice preweaning (T1 and T3) with a modified live vaccine for respiratory pathogens and 6 randomly selected calves were left unvaccinated. Whole blood samples were taken at first vaccination (T1), seven days later (T2), at revaccination and castration (T3), and at weaning (T4), and utilized for RNA isolation and sequencing. Serum from T3 and T4 was analyzed for antibodies to BRSV, BVDV1a, and BHV1. Sequenced RNA for all 48 samples was bioinformatically processed with a HISAT2/StringTie pipeline, utilizing reference guided assembly with the ARS-UCD1.2 bovine genome. Differentially expressed genes were identified through analyzing the impact of time across all calves, influence of vaccination across treatment groups at each timepoint, and the interaction of time and vaccination. Calves, regardless of vaccine administration, demonstrated an increase in gene expression over time related to specialized proresolving mediator production, lipid metabolism, and stimulation of immunoregulatory T-cells. Vaccination was associated with gene expression related to natural killer cell activity and helper T-cell differentiation, enriching for an upregulation in Th17-related gene expression, and downregulated genes involved in complement system activity and coagulation mechanisms. Type-1 interferon production was unaffected by the influence of vaccination nor time. To our knowledge, this is the first study to evaluate mechanisms of vaccination and development in healthy calves through RNA sequencing analysis.

9.
J Anim Sci ; 100(1)2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-34951640

RESUMO

This experiment evaluated ruminal, physiological, and productive responses of feedlot cattle consuming a corn-based finishing diet that included different levels of a magnesium oxide (MG) blend. Yearling cattle (58 heifers and 62 steers) were ranked by sex and initial body weight (BW; 407 ± 3.1 kg), and allocated to 4 groups of 30 animals each. Groups were housed in one of four drylot pens (30 × 12 m) equipped with GrowSafe automated feeding systems (Model 6000E, 4 bunks/pen) during the experiment (days -14 to 117). On day 0, groups were randomly assigned to receive a total-mixed ration without (CON; n = 30) or with the inclusion (as-fed basis) of MG at 0.25% (MG25; n = 30), 0.50% (MG50; n = 30), or 0.75% (MG75; n = 30) until slaughter on day 118. Individual feed intake was recorded daily, and BW was recorded every 14 d and prior to slaughter (day 117). Blood samples were collected on days 0, 28, 56, 84, and 112, and hair samples were collected on days 0, 56, and 112 from the tail-switch. On day 42, eight rumen-cannulated steers (BW = 492 ± 8.0 kg) were housed with yearling cattle (1 pair/pen). Pairs rotated among groups every 14 d, resulting in a replicated 4 × 4 Latin square design (n = 8/treatment; days 42 to 98). Rumen pH was measured on days 7 and 14 of each period (0800, 1200, 1600, and 2000 h). Orthogonal contrasts were used to determine if inclusion of MG (0%, 0.25%, 0.50%, or 0.75% of the diet) yielded linear or quadratic effects, and to explore overall effect of MG supplementation (CON vs. MG25 + MG50 + MG75). No treatment differences were noted (P ≥ 0.31) for BW gain, feed intake, or feed efficiency. Cattle supplemented with MG tended to have less carcass marbling (P = 0.07) compared with CON. Inclusion of MG linearly increased (P < 0.01) mean plasma concentrations of magnesium and tended to linearly decrease (P = 0.09) mean plasma concentrations of haptoglobin. Cattle supplemented with MG had greater (P < 0.01) mean plasma concentrations of cortisol compared with CON. Hair cortisol concentration did not differ between treatments on day 56 (P ≥ 0.25) and linearly decreased (P < 0.01) with MG inclusion on day 112 (treatment × day; P = 0.02). Inclusion of MG linearly increased (P = 0.03) mean rumen pH, but these outcomes were mostly noted during the last two sampling of the day (treatment × hour; P = 0.02). Collectively, supplemental MG was effective in controlling rumen pH in cattle receiving a corn-based finishing diet, but without improvements in feedlot performance and carcass merit.


Acidosis is a common digestive disorder in feedlot cattle consuming high-grain diets, resulting in excessive accumulation of organic acids and pH reduction in the rumen. Sub-acute acidosis is the most prevalent form of acidosis in feedlot cattle, and it is difficult to diagnose due to limited clinical signs, but directly impairs cattle health and productivity. This study evaluated the inclusion of a blend of magnesium oxide (MG) into feedlot diets, a novel neutralizing agent to control rumen pH and mitigate sub-acute acidosis. More specifically, cattle received a corn-based diet with the inclusion of MG at different levels (0%, 0.25%, 0.50%, or 0.75% of the diet). Ruminal pH increased as dietary MG inclusion increased, particularly as cattle consumed feed toward the end of the day. Concentrations of plasma haptoglobin and cortisol in the tail-switch hair decreased as dietary MG inclusion increased, indicating that MG supplementation reduced inflammatory and chronic stress resultant from sub-acute acidosis. However, no benefits from MG were noted for cattle productive traits, including growth rate, feed efficiency, and carcass merit traits. Therefore, supplemental MG appears to be effective in controlling rumen pH in cattle receiving a corn-based finishing diet, but without improvements in feedlot performance and carcass quality.


Assuntos
Ração Animal , Rúmen , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Suplementos Nutricionais , Feminino , Óxido de Magnésio
10.
Transl Anim Sci ; 6(4): txac156, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36568898

RESUMO

Cattle temperament significantly impacts production traits such as reproduction. The objective of this study was to assess the effects of temperament on pregnancy rates to fixed-timed artificial insemination (TAI) in Bos taurus beef heifers. A total of 297 Angus influenced heifers from 3 different locations were evaluated for temperament based on chute score and exit velocity on the first day of the estrus synchronization protocol (d-9) and classified by temperament type based on temperament score (calm ≤ 3 < excitable). Pregnancy status was determined by transrectal ultrasonography approximately 40 d after TAI. Hair from the tail switch was collected at d-9 and at d0 (TAI) for cumulative cortisol evaluation. A subset of 43 heifers from location 3 had blood samples collected at all handling events and evaluated for cortisol concentrations. Overall, 71% of heifers were classified as calm whereas 29% as excitable. Pregnancy rates to TAI were reduced (P = 0.042) in excitable heifers compared to calm heifers (36% vs. 55%, respectively). Mean concentration of cortisol in the hair was reduced over time (P < 0.001) from d-9 (3.5 ± 0.3 pg/mg) to d0 (1.74 ± 0.3 pg/mg) in all heifers, regardless of temperament. In addition, excitable heifers had increased circulating concentrations of cortisol when compared to calm heifers in all handling events (P = 0.015). More interestingly, despite of temperament, concentrations of circulating cortisol were reduced as the protocol events progressed, with greater cortisol concentrations on d-9, intermediate on d-3, and lesser on d0 (P = 0.031). Therefore, the present study demonstrates that heifer temperament has negative effects in pregnancy rates to TAI programs. However, according to blood cortisol concentrations, no chronic stress response was detected due to cattle handling for the TAI protocol. In fact, blood cortisol concentration was reduced between the initiation and completion of the protocol, indicating that heifers were acclimated to handing. These results support the adoption of acclimation protocols and proper cattle handling as a strategy to increase fertility of heifers that are exposed to TAI.

11.
J Anim Sci ; 100(12)2022 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-36223325

RESUMO

The objective of this study was to evaluate the use of corpus luteum (CL) color Doppler (CD) ultrasonography and pregnancy-associated glycoproteins (PAG) for early pregnancy diagnosis and examine their ability to predict late embryonic/early fetal mortality (LEM) in Bos taurus beef replacement heifers. Beef heifers (n = 178) were exposed to a 7-d CO-Synch + CIDR protocol followed by fixed-time artificial insemination (day 0). On days 20 and 22, B-mode and CD ultrasonography were performed to evaluate CL morphometries and blood perfusion, respectively. Heifers were considered nonpregnant when CL area was <2 cm2 or estimated luteal blood perfusion was ≤30% of the total luteal area. Blood samples were collected on days 25 and 29 to estimate circulating concentrations of PAG. Conventional ultrasonography on days 29 and 94 was utilized to determine pregnancy status and considered the gold standard method for pregnancy diagnosis. Pregnant heifers had greater (P < 0.01) CL diameter, area, volume, and blood perfusion when compared with nonpregnant heifers on days 20 and 22. Accuracy of CD on days 20 and 22, and PAG on days 25 and 29 were 91%, 94%, 96%, and 98%, respectively. No false-negative results were observed for CD on both days 20 and 22 (negative predicted value = 100%) and false-positive results represented 8% and 6% of the diagnoses. Heifers that experienced LEM between days 29 and 94 of gestation had decreased luteal (P = 0.02) volume on day 20 and tended (P = 0.07) to have decreased concentrations of PAG on day 29 compared with heifers that maintained pregnancy. However, both CD and PAG failed to predict embryonic mortality. In conclusion, CD successfully detected most nonpregnant replacement heifers as early as day 20 of gestation, while resulting in no false negative diagnoses. Both CD and PAG failed to predict LEM in the present study.


Identifying nonpregnant females early after breeding allows cattle producers to rapidly rebreed females that failed to conceive after their first artificial insemination and consequently increases reproductive efficiency. Additionally, embryonic and fetal mortality during early gestation are the main drivers of pregnancy failure and represents a significant economic burden to both the beef and dairy industries. This study evaluated the use of color Doppler (CD) ultrasonography of specific ovarian structures and blood concentrations of pregnancy-associated glycoproteins (PAG) as potential methods to diagnose pregnancy earlier than industry-standard techniques. Moreover, the present study investigated the use of CD and blood PAG as predictor of pregnancy loss. Data generated here indicates that CD and blood PAG can accurately detect pregnancy as early as 20 and 25 d after insemination, respectively. In the present study, heifers that experienced pregnancy loss between days 29 and 94 of gestation tended to have decreased plasma concentrations of PAG during early pregnancy. Heifers experiencing pregnancy loss between days 29 and 94 of gestation were also more likely to have a luteal cavity on day 20 of gestation and had decreased luteal volume on the same day. However, results reported herein indicate that both CD and blood concentrations of PAG failed to predict pregnancy loss in replacement heifers.


Assuntos
Corpo Lúteo , Inseminação Artificial , Bovinos , Gravidez , Animais , Feminino , Corpo Lúteo/diagnóstico por imagem , Inseminação Artificial/veterinária , Taxa de Gravidez , Ultrassonografia Doppler em Cores/veterinária , Glicoproteínas , Progesterona , Sincronização do Estro/métodos
12.
Animals (Basel) ; 11(4)2021 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-33919507

RESUMO

Nutritional management during gestation is critical to optimize the efficiency and profitability of beef production systems. Given the essentiality of trace minerals to fetal developmental processes, their supplementation represents one approach to optimize offspring productivity. Our research group investigated the impacts of supplementing gestating beef cows with organic-complexed (AAC) or inorganic sources (INR) of Co, Cu, Mn, or Zn on productive and health responses of the progeny. Calves born to AAC supplemented cows had reduced incidence of bovine respiratory disease and were >20 kg heavier from weaning until slaughter compared to unsupplemented cohorts. Complementing these findings, heifer progeny born to AAC supplemented cows had accelerated puberty attainment. Collectively, research demonstrates supplementing trace minerals to gestating beef cows may be a strategy to enhance offspring productivity in beef production systems.

13.
Animals (Basel) ; 11(6)2021 Jun 12.
Artigo em Inglês | MEDLINE | ID: mdl-34204706

RESUMO

Global beef production must increase in the next decades to meet the demands of a growing population, while promoting sustainable use of limited natural resources. Supplementing beef cattle with omega-6 fatty acids (FAs) is a nutritional approach shown to enhance production efficiency, with research conducted across different environments and sectors of the beef industry. Omega-6 FA from natural feed ingredients such as soybean oil are highly susceptible to ruminal biohydrogenation. Hence, our and other research groups have used soybean oil in the form of Ca soaps (CSSO) to lessen ruminal biohydrogenation, and maximize delivery of omega-6 FA to the duodenum for absorption. In cow-calf systems, omega-6 FA supplementation to beef cows improved pregnancy success by promoting the establishment of early pregnancy. Cows receiving omega-6 FA during late gestation gave birth to calves that were healthier and more efficient in the feedlot, suggesting the potential role of omega-6 FA on developmental programming. Supplementing omega-6 FA to young cattle also elicited programming effects toward improved adipogenesis and carcass quality, and improved calf immunocompetence upon a stress stimulus. Cattle supplemented with omega-6 FA during growing or finishing periods also experienced improved performance and carcass quality. All these research results were generated using cattle of different genetic composition (Bos taurus and B. indicus influenced), and in different environments (tropical, subtropical, and temperate region). Hence, supplementing omega-6 FA via CSSO is a sustainable approach to enhance the production efficiency of beef industries across different areas of the world.

14.
J Anim Sci ; 99(6)2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33715010

RESUMO

One hundred and ninety nonlactating, pregnant beef cows (¾ Bos taurus and » Bos indicus; 138 multiparous and 52 primiparous) were assigned to this experiment at 117 ± 2.2 d of gestation (day 0). Cows were ranked by parity, pregnancy type (artificial insemination = 102, natural service = 88), body weight (BW) and body condition score, and assigned to receive a supplement containing: (1) sulfate sources of Cu, Co, Mn, and Zn (INR; n = 95) or (2) an organic complexed source of Cu, Mn, Co, and Zn (AAC; Availa4; Zinpro Corporation, Eden Prairie, MN; n = 95). The INR and AAC provided the same daily amount of Cu, Co, Mn, and Zn, based on 7 g of the AAC source. From day 0 to calving, cows were maintained in a single pasture and segregated 3 times weekly into 1 of 24 individual feeding pens to receive treatments. Calves were weaned on day 367 (200 ± 2 d of age), managed as a single group for a 45-d preconditioning period (days 367 to 412), and transferred to a single oat (Avena sativa L.) pasture on day 412. Heifer calves were moved to an adjacent oat pasture on day 437, where they remained until day 620. Heifer puberty status was verified weekly (days 437 to 619) based on plasma progesterone concentrations. Steer calves were shipped to a commercial feedlot on day 493, where they were managed as a single group until slaughter (day 724). Plasma cortisol concentration was greater (P = 0.05) in AAC calves at weaning but tended to be less (P = 0.10) on day 370 compared with INR calves. Mean plasma haptoglobin concentration was greater (P = 0.03) in INR vs. AAC calves during preconditioning, and no treatment effects were noted (P = 0.76) for preconditioning average daily gain (ADG). Puberty attainment was hastened in AAC heifers during the experiment (treatment × day; P < 0.01), despite similar (P = 0.39) ADG between treatments from days 412 to 620. Expression of myogenin mRNA in the longissimus muscle was greater (P = 0.05) in INR vs. AAC heifers on day 584. No treatment effects were detected (P ≥ 0.24) for steer ADG from day 412 until slaughter, nor for carcass quality traits. Hepatic mRNA expression of metallothionein 1A was greater (P = 0.02) in INR vs. AAC steers on day 586. In summary, supplementing Co, Cu, Zn, and Mn as organic complexed instead of sulfate sources to beef cows during the last 5 mo of gestation did not improve performance and physiological responses of the steer progeny until slaughter, but hastened puberty attainment in the female progeny reared as replacement heifers.


Assuntos
Ração Animal , Dieta , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Suplementos Nutricionais , Feminino , Gravidez , Maturidade Sexual , Zinco
15.
J Anim Sci ; 99(5)2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33758933

RESUMO

One hundred and ninety non-lactating, pregnant beef cows (three-fourth Bos taurus and one-fourth Bos indicus; 138 multiparous and 52 primiparous) were assigned to this experiment at 117 ± 2.2 d of gestation (day 0). Cows were ranked by parity, pregnancy type (artificial insemination = 102 and natural service = 88), body weight (BW), and body condition score (BCS) and assigned to receive a supplement containing: 1) sulfate sources of Cu, Co, Mn, and Zn (INR; n = 95) or 2) an organic-complexed source of Cu, Mn, Co, and Zn (AAC; Availa 4; Zinpro Corporation, Eden Prairie, MN; n = 95). The INR and AAC provided the same daily amount of Cu, Co, Mn, and Zn, based on 7 g of the AAC source. From day 0 to calving, cows were maintained in a single pasture and were segregated three times weekly into 1 of the 24 individual feeding pens to receive treatments. Cow BW and BCS were recorded on days -30, 97, upon calving, and at weaning (day 367). Milk production was estimated at 42 ± 0.5 d postpartum via weigh-suckle-weigh (WSW) method. Liver biopsies were performed in 30 cows per treatment on days -30, 97, upon calving, and the day after WSW. Calf BW was recorded at birth and weaning. Liver and longissimus muscle (LM) biopsies were performed in 30 calves per treatment upon calving and 24 h later, the day after WSW, and at weaning. No treatment effects were detected (P ≥ 0.49) for cow BCS during gestation, despite AAC cows having greater (P = 0.04) BW on day 97. Liver Co concentrations were greater (P < 0.01) for AAC compared with INR cows, and liver concentrations of Cu were greater (P = 0.02) for INR compared with AAC cows on day 97. Upon calving, INR cows had greater (P ≤ 0.01) liver Cu and Zn concentrations compared with AAC cows. No other treatment differences were noted (P ≥ 0.17) for cow and calf liver trace mineral concentrations. Cows receiving AAC had greater (P = 0.04) hepatic mRNA expression of metallothionein 1A at calving, and their calves had greater (P = 0.04) hepatic mRNA expression of superoxide dismutase at weaning. Milk production did not differ between AAC and INR cows (P = 0.70). No treatment effects were detected (P ≥ 0.29) for mRNA expression of LM genes associated with adipogenic or muscle development activities in calves at birth and weaning. Calf birth and weaning BW also did not differ (P ≥ 0.19) between treatments. In summary, supplementing AAC or INR to beef cows during the last 5 mo of gestation yielded similar cow-calf productive responses until weaning.


Assuntos
Ração Animal , Dieta , Ração Animal/análise , Animais , Bovinos , Dieta/veterinária , Suplementos Nutricionais , Feminino , Lactação , Gravidez , Desmame , Zinco
16.
Can J Aging ; 39(3): 373-384, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31391142

RESUMO

Group-exercise instructors are a vital social determinant of exercise enjoyment, attendance, and adherence. Instructors also affect the degree to which physical cultures are socially inclusive. In order to elucidate the roles that instructors play in affecting these outcomes, we conducted a scoping review. Scoping reviews are a preliminary method for assessing the breadth and depth of existing literature in order to identify key themes and gaps therein. Based on Arksey and O'Malley's (2005) framework, we identified 52 articles and book chapters, 33 of which were older-adult specific, using a university search engine that simultaneously searches multiple databases. We conceptually mapped the literature, which revealed instructors' vital roles as: (1) constructors of group social cohesion, (2) cultural intermediaries, (3) competent practitioners, (4) leaders and communicators, and (5) educators. Of these, the instructor's educative role lacks empirical attention. We conclude with implications for future research, practice, and policy.


Assuntos
Envelhecimento , Exercício Físico , Educação Física e Treinamento/normas , Idoso , Humanos , Relações Interpessoais , Liderança
17.
Can J Aging ; 36(4): 501-513, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28914223

RESUMO

This study investigated the state of gerontology content in health and social service education programs in Ontario, and readiness indicators for change among administrators and faculty. We conducted a survey of teaching faculty (n = 100) and deans or directors (n = 56) of 89 education programs, which revealed mixed evidence on readiness for change. Most respondents thought their programs were adequate but needed enhancement. However, they were unaware of published gerontological competencies with which to evaluate their curricula. Beliefs about capacity for change varied, with half the participants indicating that their programs had sufficient faculty expertise in gerontology and geriatrics. Factors influencing readiness for change include lack of gerontological expertise; need for institutional and management support; need for additional teaching resources; and recognizing the need for change. There is an opportunity, by committing resources and time, to capitalize on the faculty and administrators who thought their programs should improve.


Assuntos
Ocupações Relacionadas com Saúde/educação , Currículo/tendências , Educação Médica/organização & administração , Geriatria/educação , Serviço Social/educação , Universidades/organização & administração , Humanos , Ontário , Inovação Organizacional , Inquéritos e Questionários
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