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1.
J Anim Sci ; 1012023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37967310

RESUMO

Feed and water intake are two important aspects of cattle production that greatly impact the profitability, efficiency, and sustainability of producers. Feed and, to a lesser degree, water intake have been studied previously; however, there is little research on their associated animal behaviors and there is a lack of standardized phenotypes for these behaviors. Feed and water intakes obtained with an Insentec system (Hokofarm Group, The Netherlands) from 830 crossbred steers were used to compute five intake behaviors for both feed and water: daily sessions (DS), intake rate (IR), session size (SS), time per session (TS), and session interval (SI). Variance components and heritabilities were estimated for each trait. Heritabilities for feed intake behaviors were 0.50 ±â€…0.12, 0.63 ±â€…0.12, 0.40 ±â€…0.13, 0.35 ±â€…0.12, and 0.60 ±â€…0.12 for DS, IR, SS, TS, and SI, respectively. Heritabilities for water intake behaviors were 0.56 ±â€…0.11, 0.88 ±â€…0.07, 0.70 ±â€…0.11, 0.54 ±â€…0.12, and 0.80 ±â€…0.10 for NS, IR, SS, TS, and SI, respectively. Daily dry matter intake (DDMI) and daily water intake (DWI) had heritabilities of 0.57 ±â€…0.11 and 0.44 ±â€…0.11. Phenotypic correlations varied between pairs of traits (-0.83 to 0.82). Genetic correlations between DDMI and feed intake behaviors were moderate to high, while genetic correlations between DWI and water intake behaviors were low to moderate. Several significant single nucleotide polymorphisms (SNP) were identified for the feed and water intake behaviors. Genes and previously reported quantitative trait loci near significant SNPs were evaluated. The results indicated that feed and water intake behaviors are influenced by genetic factors and are heritable, providing one additional route to evaluate or manipulate feed and water intake.


Feed and water intake are important aspects of cattle production to understand because they impact producer profitability and sustainability. While feed intake and, to a lesser degree, water intake have previously been studied, the associated feeding and drinking behaviors are relatively unknown and lack standardized phenotypes. Using individual animal feed and water intake records, five behaviors were evaluated for feed and water intake from crossbred feedlot steers. The behaviors evaluated were daily sessions (no./d), session size (kg), time per session (s), intake rate (g/s), and session interval (min). The impact of season (winter vs. summer) and bunk management (ad libitum vs. slick) on feeding and drinking behaviors was evaluated. Heritability and variance components were estimated for all feeding and drinking behaviors. Pairwise phenotypic correlations between behaviors were discussed. The relationship between intake and feeding or drinking behaviors was evaluated with genetic correlations. A genome-wide association study identified several significant single nucleotide polymorphisms for feeding and drinking behaviors. The results indicate that feeding and drinking behaviors are heritable and may be one additional route to evaluate feed and water intake.


Assuntos
Ração Animal , Ingestão de Líquidos , Bovinos/genética , Animais , Ingestão de Alimentos/genética , Comportamento Animal , Água
2.
Cureus ; 15(9): e46012, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37900410

RESUMO

Introduction Currently, there is no recommendation for adjustments to the Best Timed Pathway for Prostate cancer (BTiPP) depending on whether the referral is for raised prostate-specific antigen (PSA) or malignant-feeling prostate on digital rectal examination (DRE). Therefore, all patients undergo MRI scanning. We aim to establish if patients with abnormal DRE only (without raised PSA) should have an adjusted pathway by comparing the biopsy rate and diagnostic yield after an MRI scan. Methods All BTiPP 2021 referral patient notes were reviewed. The patients were categorized into the aDRE group (abnormal DRE with normal PSA) or the rPSA group (raised PSA with or without abnormal DRE). Data and results for MRI and prostate biopsy were evaluated. Diagnostic yield was defined as the percentage of patients who underwent an MRI, who were diagnosed with biopsy-proven cancer. Results 68.5% (74/108) and 70.9% (282/398) of patients underwent upfront MRI in the aDRE and rPSA groups, respectively. Following MRI, the biopsy rate (28.4% (21/74) vs. 42.9% (121/282) (p=0.02)) and the biopsy-proven diagnostic yield (20.3% (15/74) vs. 36.9% (104/282) (p<0.01)) were both significantly lower in the aDRE group. 58% (43/74) of patients in the aDRE group had no posterior lesions on MRI. Only 6.7% (1/15) of biopsy-proven cancers in the aDRE group were solely anterior. Conclusions After MRI, the biopsy rate and diagnostic yield were significantly lower in the aDRE group compared to the rPSA group. Furthermore, a majority of patients referred for aDRE had a normal posterior prostate appearance on MRI. An adjusted pathway for patients referred for aDRE with normal PSA, with DRE by a urologist prior to MRI, should be considered as it would likely reduce unnecessary investigations, treatment, and patient anxiety. These data suggest that this would not risk missing significant cancers.

3.
J Anim Sci ; 1012023 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-37328159

RESUMO

Enteric methane is a potent greenhouse gas and represents an escape of energy from the ruminant digestive system. Additive genetic variation in methane production suggests that genetic selection offers an opportunity to diminish enteric methane emissions. Logistic and monetary difficulties in directly measuring methane emissions can make genetic evaluation on an indicator trait such as predicted methane production a more appealing option, and inclusion of genotyping data can result in greater genetic progress. Three predicted methane production traits were calculated for 830 crossbred steers fed in seven groups. The methane prediction equations used included mathematical models from Ellis et al. (2007), Mills et al. (2003), and IPCC (2019). Pearson correlations between the traits were all greater than 0.99, indicating that each prediction equation behaved similarly. Further, the Spearman correlations between the estimated breeding values for each trait were also 0.99, which suggests any of the predicted methane models could be used without substantially changing the ranking of the selection candidates. The heritabilities of Ellis, Mills, and IPCC predicted methane production were 0.60, 0.62, and 0.59, respectively. A genome-wide association study identified one single nucleotide polymorphism (SNP) that reached the threshold for significance for all of the traits on chromosome 7 related to oxidoreductase activity. Additionally, the SNP slightly below the significance threshold indicate genes related to collagen, intracellular microtubules, and DNA transcription may play a role in predicted methane production or its component traits.


Cattle produce methane, a greenhouse gas, as a byproduct of their digestion. It is possible to breed for animals which naturally produce less methane; however, measuring animals for methane production can be difficult or expensive and is required for effective selection. Therefore, an alternative solution is to use a mathematical model to predict methane production and select for animals with low predicted methane. The heritability of predicted methane production from each model ranged from 0.59 to 0.62. Animals were ranked nearly identical, regardless of model used. A genome-wide association study was also conducted to determine what loci may be related to predicted methane production. One significant locus was identified on chromosome 7 related to oxidoreductase activity. Other loci approaching significance showed that genes related to collagen production, intracellular microtubule binding, and DNA transcription may be related to predicted methane production. In particular, collagen turnover may have a relationship to predicted methane because it affects growth rate, which is driven by dry matter intake, which, in turn, is the primary driver of predicted methane production.


Assuntos
Estudo de Associação Genômica Ampla , Genoma , Bovinos/genética , Animais , Estudo de Associação Genômica Ampla/veterinária , Fenótipo , Metano , Polimorfismo de Nucleotídeo Único , Dieta
4.
Transl Anim Sci ; 7(1): txad047, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37250344

RESUMO

The objectives of this experiment were to evaluate the effects of feeding Bacillus subtilis PB6 on clinical health, performance, and carcass characteristics of feedlot steers. Bos indicus crossbred steer calves (n = 397; 342 kg initial body weight [BW]) were randomly assigned to pens by initial BW; pens (n = 24) were randomly assigned to one of two of the following experimental treatments: 1) no supplemental dietary direct-fed microbial, control (CON; n = 12 pens) or 2) 13 g/steer daily B. subtilis PB6 (CLO; CLOSTAT, Kemin Industries, Des Moines, IA; n = 12 pens). Steers were housed in 12.2 × 30.5 m soil-surfaced pens; pen served as the experimental unit. The percentage of cattle treated once or twice for bovine respiratory disease (BRD) did not differ among treatments (P ≥ 0.27); BRD mortality also did not differ between CON and CLO (P = 0.34). During the receiving period, final BW (P = 0.97), average daily gain (ADG; P = 0.91), dry matter intake (DMI; P = 0.77), and gain:feed (P = 0.79) were not different among treatments. There was a tendency (P = 0.09) for CLO-supplemented steers to be 14% more efficient from days 0 to 14 of the receiving period. Final BW, overall finishing phase ADG, and DMI did not differ by treatment (P ≥ 0.14); ADG was 0.14 kg greater for CLO than CON (P = 0.03) from days 29 to 56 of the finishing period. Gain: feed tended (P = 0.07) to be 7% greater (0.144 vs. 0.141) for CLO than CON throughout the duration of the finishing period, and 6.7% greater (P = 0.08; 0.152 for CLO vs. 0.150 for CON) for the entirety of the experiment. Carcass traits did not differ among treatments (P ≥ 0.31). The results of this experiment suggest that supplementing 13 g/steer daily B. subtilis PB6 may improve feed efficiency in feedlot cattle.

5.
JBMR Plus ; 6(10): e10682, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36248271

RESUMO

A primary osteoporosis prevention program using a virtual bone health team (BHT) was implemented to comanage the care of rural veterans in the Mountain West region of the United States. The BHT identified, screened, and treated rural veterans at risk for osteoporosis using telephone and United States Postal Service communications. Eligibility was determined by regular use of Veterans Health Administration primary care, age 50 or older, and evidence of fracture risk. This study was conducted to identify demographic and clinical factors associated with the acceptance of osteoporosis screening and the initiation of medication where indicated. A cross-sectional cohort design (N = 6985) was utilized with a generalized estimating equation and logit link function to account for facility-level clustering. Fully saturated and reduced models were fitted using backward selection. Less than a quarter of eligible veterans enrolled in BHT's program and completed screening. Factors associated with a lower likelihood of clinic enrollment included being of older age, unmarried, greater distance from VHA services, having a copayment, prior fracture, or history of rheumatoid arthritis. A majority of veterans with treatment indication started medication therapy (N = 453). In this subpopulation, Fisher's exact test showed a significant association between osteoporosis treatment uptake and a history of two or more falls in the prior year, self-reported parental history of fracture, current smoking, and weight-bearing exercise. The BHT was designed to reduce barriers to screening; however, for this population cost and travel continue to limit engagement. The remarkable rate of medication initiation notwithstanding, low enrollment reduces the impact of this primary prevention program, and findings pertaining to fracture, smoking, and exercise imply that health beliefs are an important contributing factor. Efforts to identify and address barriers to osteoporosis screening and treatment, such as clinical factors, social determinants of health, and health beliefs, may pave the way for effective implementation of population bone health care delivery systems. Published 2022. This article is a U.S. Government work and is in the public domain in the USA. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.

6.
Cureus ; 14(9): e28794, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-36225457

RESUMO

BACKGROUND/OBJECTIVE:  Acute appendicitis (AA) is predominantly managed with appendectomy, but can be treated non-operatively, leading to a high risk of recurrence. Non-operative management has been more common since the COVID-19 pandemic affected the feasibility of performing surgery. This case-control study analyzed non-operatively managed patients in order to identify clinical and radiological factors associated with recurrence risk.  Methods: Over 12 months, 48 adults with CT-proven AA managed non-operatively were identified, and followed up for at least six further months to assess them for recurrence (readmission to hospital more than 14 days after discharge and after symptom resolution, requiring treatment for appendicitis). Clinical and CT data were collected and a Cox regression survival analysis was performed to produce hazards ratios (HRs). RESULTS:  Of the 48 patients, 12 (25%) experienced a recurrence up until the end of the follow-up period, eight of whom were then treated operatively, and four treated non-operatively. On the univariate analysis, greater recurrence risk was observed in patients with diabetes mellitus, higher heart rate (on admission and maximum value during admission), lower white cell count and neutrophils and appendiceal wall thinning on CT. On the multivariate analysis, diabetes mellitus (HR=7.72, p=0.021) and higher heart rate (HR=1.08, p=0.018) were associated with statistically significant greater recurrence risk. CONCLUSIONS:  Diabetes mellitus and higher heart rate on admission are associated with greater recurrence risk of AA managed non-operatively. No CT findings were associated with statistically significant greater risk. Clinicians should, therefore, consider DM and heart rate when making decisions on appendicitis management, especially during the COVID-19 pandemic but also beyond it.

7.
New Phytol ; 233(1): 84-118, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34515358

RESUMO

Crop diversity underpins the productivity, resilience and adaptive capacity of agriculture. Loss of this diversity, termed crop genetic erosion, is therefore concerning. While alarms regarding evident declines in crop diversity have been raised for over a century, the magnitude, trajectory, drivers and significance of these losses remain insufficiently understood. We outline the various definitions, measurements, scales and sources of information on crop genetic erosion. We then provide a synthesis of evidence regarding changes in the diversity of traditional crop landraces on farms, modern crop cultivars in agriculture, crop wild relatives in their natural habitats and crop genetic resources held in conservation repositories. This evidence indicates that marked losses, but also maintenance and increases in diversity, have occurred in all these contexts, the extent depending on species, taxonomic and geographic scale, and region, as well as analytical approach. We discuss steps needed to further advance knowledge around the agricultural and societal significance, as well as conservation implications, of crop genetic erosion. Finally, we propose actions to mitigate, stem and reverse further losses of crop diversity.


Assuntos
Conservação dos Recursos Naturais , Produtos Agrícolas , Agricultura , Produtos Agrícolas/genética , Ecossistema
8.
Front Physiol ; 13: 1037417, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36699679

RESUMO

Adenosine triphosphate (ATP) and its metabolites drive microglia migration and cytokine production by activating P2X- and P2Y- class purinergic receptors. Purinergic receptor activation gives rise to diverse intracellular calcium (Ca2+ signals, or waveforms, that differ in amplitude, duration, and frequency. Whether and how these characteristics of diverse waveforms influence microglia function is not well-established. We developed a computational model trained with data from published primary murine microglia studies. We simulate how purinoreceptors influence Ca2+ signaling and migration, as well as, how purinoreceptor expression modifies these processes. Our simulation confirmed that P2 receptors encode the amplitude and duration of the ATP-induced Ca2+ waveforms. Our simulations also implicate CD39, an ectonucleotidase that rapidly degrades ATP, as a regulator of purinergic receptor-induced Ca2+ responses. Namely, it was necessary to account for CD39 metabolism of ATP to align the model's predicted purinoreceptor responses with published experimental data. In addition, our modeling results indicate that small Ca2+ transients accompany migration, while large and sustained transients are needed for cytokine responses. Lastly, as a proof-of-principal, we predict Ca2+ transients and cell membrane displacements in a BV2 microglia cell line using published P2 receptor mRNA data to illustrate how our computer model may be extrapolated to other microglia subtypes. These findings provide important insights into how differences in purinergic receptor expression influence microglial responses to ATP.

9.
Plants (Basel) ; 10(12)2021 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-34961233

RESUMO

Genebanks were established out of a recognised need not just to provide genetic variation to support breeding objectives but to prevent crop diversity from being lost entirely for future users. Such conservation objectives may have led, over the past few decades, to a gradually diminishing connection between genebanks and current users of diversity. While there continues to be large-scale distribution of germplasm from genebanks to recipients worldwide, relatively little is known or published about the detailed trends in the demand for genebank materials. Meanwhile, the rapid expansion of the applications and uses of modern genomic technologies and approaches is, undoubtedly, having a transformational impact on breeding, research and the demand for certain genetic resources and associated data. These trends will require genebanks to be responsive and to adapt. They also provide important opportunities for genebanks to reorganize and become more efficient individually and as a community. Ultimately, future challenges and opportunities are likely to drive more demand for genetic diversity and provide an important basis for genebanks to gear up.

10.
Plants (Basel) ; 10(11)2021 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-34834625

RESUMO

Plant genebanks provide genetic resources for breeding and research programs worldwide. These programs benefit from having access to high-quality, standardized phenotypic and genotypic data. Technological advances have made it possible to collect phenomic and genomic data for genebank collections, which, with the appropriate analytical tools, can directly inform breeding programs. We discuss the importance of considering genebank accession homogeneity and heterogeneity in data collection and documentation. Citing specific examples, we describe how well-documented genomic and phenomic data have met or could meet the needs of plant genetic resource managers and users. We explore future opportunities that may emerge from improved documentation and data integration among plant genetic resource information systems.

11.
Transl Anim Sci ; 5(3): txab104, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34278238

RESUMO

Two experiments were conducted to determine the effects of feeder design on hay intake, apparent diet digestibility, and hay waste in gestating beef cows. Native tallgrass prairie hay and a protein supplement was fed throughout both experiments. In Exp. 1, 56 crossbred cows were used in a Latin square arrangement. Feeder design treatments included a conventional open bottom steel ring (OBSR), an open bottom polyethylene pipe ring (POLY); a sheeted bottom steel ring (RING), and a sheeted bottom steel ring with a basket (BASK). Cows were weighed and allotted based on BW to one of four previously grazed 2.0 ha paddocks equipped with a concrete feeding pad. Fourteen cows were assigned to each paddock and three round bales were fed consecutively within each treatment period. The cows acclimated to the feeders while the first bale was being consumed. Subsequently, hay waste data were collected while the second and third bale within each period were being consumed. Waste was measured for each bale at 24, 48, 72, and 96 h after each bale was introduced into the pen. Hay waste was significantly affected by hay feeder design with 19.7, 21.1, 12.4, and 5.5% of original bale weight wasted for OBSR, POLY, RING, and BASK, respectively (P < 0.01). There was a feeder design × day interaction (P < 0.01) with greater waste when the bale was first introduced into the pen in OBSR, POLY, and RING feeders and gradually declining thereafter, while waste from the BASK feeder was consistently low. There was a tendency (P = 0.06) for cows eating from OBSR feeders to consume less hay than cows eating from RING feeders. Feeder design did not influence apparent diet digestibility (P = 0.46). In Exp. 2, 64 crossbred cows (body weight = 590 ± 59 kg) were used to determine waste, forage intake, and apparent diet digestibility when hay was fed from a sheeted bottom steel ring (RING) or a RING feeder with a cone insert (CONE). More hay was wasted when cows were fed from RING feeders compared to CONE feeders (11.9% vs. 4.8%, P < 0.01). Feeder design had no effect on DMI or apparent digestibility (P > 0.45). Hay savings from adopting a more conservative feeder design can have a dramatic influence on hay utilization by beef cows and thus on cost of production.

12.
BMJ Case Rep ; 14(3)2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33722915

RESUMO

Recreational nitrous oxide (N2O) is commonly used among young people partly due to its low cost and accessibility, and awareness of its potential adverse effects is poor in this group. One such adverse effect is degeneration of the spinal cord due to its disruption of DNA synthesis by inactivating cobalamin (B12).A 19-year-old man presented to the emergency department with a 4-week history of worsening paraesthesia in his fingers and lower limbs, and weakness in the hands and lower limbs for 2 weeks. On examination, he had an ataxic gait, reduced power of grip strength and ankle movements, and impaired sensation in the lower limbs. An MRI brain and spine revealed myelopathy of the cervical and thoracic cord.On further questioning, he reported recreational N2O inhalation. His symptoms improved after stopping this and he was treated with supplementation of B vitamins. Education strategies regarding the risks of N2O misuse are indicated.


Assuntos
Óxido Nitroso , Doenças da Medula Espinal , Degeneração Combinada Subaguda , Deficiência de Vitamina B 12 , Humanos , Imageamento por Ressonância Magnética , Masculino , Óxido Nitroso/efeitos adversos , Óxidos , Doenças da Medula Espinal/induzido quimicamente , Doenças da Medula Espinal/tratamento farmacológico , Vitamina B 12 , Deficiência de Vitamina B 12/induzido quimicamente , Deficiência de Vitamina B 12/tratamento farmacológico , Adulto Jovem
13.
Waste Manag ; 119: 267-274, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33099071

RESUMO

Policy making involves translating political visions into programs that seek to change a social behavior. To design these programs, decision makers must consider multiple aspects to achieve sustainable solutions. Furthermore, decision makers must manage interrelated information and preferences of different stakeholders to ensure the policy suits the community and accomplishes its goals. This research provides evidence of the applicability of the Choosing by Advantages (CBA) decision system to make environmental public policies, in particular to design a waste collection program for a city in Canada. The methodology is based on a case study where CBA was used to choose the recycling, organics, and PAYT (Pay as you throw) utility components of the program. To analyze the process, researchers measured decision makers' perceptions of levels of satisfaction or frustration during the program-design process by conducting surveys with decision-makers at different stages in time. The research also measured decision-makers' preference for applying CBA over traditional practices where no formal decision-making method is used, in terms of (1) reaching consensus and transparency, (2) making complex decisions, and (3) making faster decisions. The results show that CBA helped to include multiple aspects in designing for sustainability, and to consider the municipality and community preferences into the program. The study also evidenced that satisfaction levels increased as the process progressed. Finally, 75% of decision makers reported preference for CBA regarding reaching consensus and transparency, while this preference was milder (55%) regarding making complex decisions, and the opposite (27%) regarding making faster decisions.


Assuntos
Formulação de Políticas , Reciclagem , Canadá , Tomada de Decisões , Inquéritos e Questionários
14.
Transl Anim Sci ; 4(1): 102-117, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32704971

RESUMO

Growth-promoting technologies such as implants, ionophores, and ß-agonists improve feedlot performance, efficiency, and carcass characteristics of cattle. The objective of this experiment was to determine the effects of dose and duration of ractopamine hydrochloride (RH) on feedlot performance and carcass characteristics when fed to Holstein steers. A randomized complete block design was used with a 3 × 3 factorial arrangement of treatments with 3 RH doses (0, 300, or 400 mg∙steer-1∙d-1) fed for 3 durations (28, 35, or 42 d). Holstein steers (n = 855; initial body weight [BW] = 448 ± 37 kg) were blocked by BW and randomly allocated to 1 of 9 pens (15 blocks; 9 dose × duration treatment combinations) approximately 72 d before harvest. Weekly pen weights, chute temperament scores, and animal mobility were determined during the RH feeding period. At harvest, carcass data were collected on all steers, and tenderness was measured on steaks from 3 or 4 randomly selected steers from each pen and slice shear force (SSF) was determined on one steak selected from each side of the carcass after aging for 14 or 21 d. For feedlot performance, carcass characteristics, and SSF, no dose × duration interactions were observed (P ≥ 0.11). With increasing RH dose, average daily gain (ADG) and gain-to-feed ratio (G:F) increased linearly (P ≤ 0.01), whereas BW gain increased linearly with RH dose and duration (P ≤ 0.01). Hot carcass weight (P = 0.02) and longissimus muscle (LM) area (P ≤ 0.01) increased linearly with increasing RH dose. The percentage of carcasses in the USDA Yield Grade 2 category increased linearly (P ≤ 0.01) and percentage of carcasses in the USDA Yield Grade 4 category tended (P = 0.08) to decrease linearly as RH dose increased. In the 14-d aged steaks, the percentage of steaks with SSF ≤ 15.3 kg decreased linearly (P ≤ 0.01), whereas the percentage of steaks with ≥20.0 kg SSF increased linearly (P ≤ 0.01) with increasing RH dose. After 21-d aging, there was a tendency (P = 0.06) for a greater percentage of steaks from steers fed RH to have SSF ≥ 20.0 kg (2% of total steaks), but no difference (P ≥ 0.12) in the percentage of steaks with SSF ≤ 19.9 kg. Final chute temperament (P ≥ 0.45) and animal mobility (P ≥ 0.67) scores were not affected by feeding RH. Increasing the dose of RH (300 or 400 mg∙steer-1∙d-1) fed for 28 to 42 d before harvest increased ADG, G:F, hot carcass weight, and LM area when fed to Holstein steers with no negative effects on behavior or mobility. The percentage of steaks classified as not tender improved when steaks were aged for 21 d from steers treated with RH.

15.
J Anim Sci ; 97(12): 4770-4782, 2019 Dec 17.
Artigo em Inglês | MEDLINE | ID: mdl-31740941

RESUMO

In the future, water may not be as readily available due to increases in competition from a growing human population, wildlife, and other agricultural sectors, making selection for water efficiency of beef cattle increasingly important. Substantial selection emphasis has recently been placed on feed efficiency in an effort to reduce production costs, but no emphasis has been placed on making cattle more water efficient due to lack of data. Thus, the objective of this study was to calculate water efficiency metrics for cattle and evaluate their relationship to growth, feed intake (FI), and feed efficiency. Individual daily FI and water intake (WI) records were collected on 578 crossbred steers over a 70-d test period. Animals with low water intake ate less feed, had lower gains, and were more water efficient (as defined by water to gain ratio, W/G, and residual water intake, RWI). However, the amount of water consumed by animals had minimal phenotypic relationship with feed efficiency (residual feed intake [RFI], R2 = 0.1050 and feed to gain ratio (F/G) ratio R2 = 0.0726). Cattle that had low DMI consumed less water, had lower gains, had lower RFI, and had higher F/G. The level of feed consumed had minimal relationship with water efficiency. WI, W/G, RWI, and ADG had moderate heritability estimates of 0.39, 0.39, 0.37, and 0.37, respectively. High heritability estimates were observed for DMI and RFI (0.67 and 0.65, respectively). Feed to gain had a low heritability estimate of 0.16. WI had a strong positive genetic correlation with W/G (0.99) and RWI (0.88), thus selecting for decreased WI should also make cattle more water efficient. The genetic correlation between WI and ADG was 0.05; thus, selecting for low WI cattle should have little effect on growth. There is a low to moderate genetic correlation between WI and DMI (0.34). RWI has a positive genetic correlation with W/G ratio (0.89) and F/G ratio (0.42) and is negatively genetically correlated with RFI (-0.57). Water to gain and F/G had a strong positive genetic correlation (0.68). RFI has a positive genetic correlation with W/G ratio (0.37) and F/G (0.88). Minimal antagonisms seem to be present between WI and ADG, although it should be noted that standard errors were large and often not significantly different from zero due to the small sample size. However, care should be taken to ensure that unintended changes do not occur in DMI or other production traits and incorporation of WI into a selection index would likely prove to be the most effective method for selection.


Assuntos
Bovinos/fisiologia , Ingestão de Líquidos , Água , Animais , Metabolismo Energético , Comportamento Alimentar , Masculino , Modelos Biológicos
16.
Bio Protoc ; 8(9)2018 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-30406159

RESUMO

Cell-derived vesicles facilitate the isolation of transmembrane proteins in their physiological membrane maintaining their structural and functional integrity. These vesicles can be generated from different cellular organelles producing, housing, or transporting the proteins. Combined with single-molecule imaging, isolated organelle specific vesicles can be employed to study the trafficking and assembly of the embedded proteins. Here we present a method for organelle specific single molecule imaging via isolation of ER and plasma membrane vesicles from HEK293T cells by employing OptiPrep gradients and nitrogen cavitation. The isolation was validated through Western blotting, and the isolated vesicles were used to perform single molecule studies of oligomeric receptor assembly.

17.
J Anim Sci ; 96(10): 4368-4384, 2018 Sep 29.
Artigo em Inglês | MEDLINE | ID: mdl-30169660

RESUMO

Water is an essential nutrient, but there are few recent studies that evaluate how much water individual beef cattle consume and how environmental factors affect an individual's water intake (WI). Most studies have focused on WI of whole pens rather than WI of individual animals. Thus, the objective of this study was to evaluate the impact of environmental parameters on individual-animal WI across different seasons and develop prediction equations to estimate WI, including within different environments and management protocols. Individual daily feed intake and WI records were collected on 579 crossbred steers for a 70-d period following a 21-d acclimation period for feed and water bunk training. Steers were fed in 5 separate groups over a 3-yr period from May 2014 to March 2017. Individual weights were collected every 14 d and weather data were retrieved from the Oklahoma Mesonet's Stillwater station. Differences in WI as a percent of body weight (WI%) were analyzed accounting for average temperature (TAVG), relative humidity (HAVG), solar radiation (SRAD), and wind speed (WSPD). Seasonal (summer vs. winter) and management differences (ad libitum vs. slick bunk) were examined. Regression analysis was utilized to generate 5 WI prediction equations (overall, summer, winter, slick, and ad libitum). There were significant (P < 0.05) differences in WI between all groups when no environmental parameters were included in the model. Although performance was more similar after accounting for all differences in weather variables, significant (P < 0.05) seasonal and feed management differences were still observed for WI%, but were less than 0.75% of steer body weight. The best linear predictors of daily WI (DWI) were dry mater intake (DMI), metabolic body weights (MWTS), TAVG, SRAD, HAVG, and WSPD. Slight differences in the coefficient of determinations for the various models were observed for the summer (0.34), winter (0.39), ad libitum (0.385), slick bunk (0.41), and overall models (0.40). Based on the moderate R2 values for the WI prediction equations, individual DWI can be predicted with reasonable accuracy based on the environmental conditions that are present, MWTS, and DMI consumed, but substantial variation exists in individual animal WI that is not accounted for by these models.


Assuntos
Bovinos/fisiologia , Ingestão de Líquidos , Meio Ambiente , Água/metabolismo , Ração Animal , Animais , Peso Corporal , Bovinos/crescimento & desenvolvimento , Ingestão de Alimentos , Masculino , Modelos Estatísticos , Oklahoma , Estações do Ano , Tempo (Meteorologia)
18.
J Anim Sci ; 96(8): 3043-3054, 2018 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-29790937

RESUMO

Water is an essential nutrient, but the effect it has on performance generally receives little attention. There are few systems and guidelines for collection of water intake (WI) phenotypes in beef cattle, which makes large-scale research on WI a challenge. The Beef Improvement Federation has established guidelines for feed intake (FI) and ADG tests, but no guidelines exist for WI. The goal of this study was to determine the test duration necessary for collection of accurate WI phenotypes. To facilitate this goal, individual daily WI and FI records were collected on 578 crossbred steers for a total of 70 d using an Insentec system at the Oklahoma State University Willard Sparks Beef Research Unit. Steers were fed in five groups and were individually weighed every 14 d. Within each group, steers were blocked by BW (low and high) and randomly assigned to one of four pens containing approximately 30 steers per pen. Each pen provided 103.0 m2 of shade and included an Insentec system containing six feed bunks and one water bunk. Steers were fed a constant diet across groups and DMI was calculated using the average of weekly percent DM within group. Average FI and WI for each animal were computed for increasingly large test durations (7, 14, 21, 28, 35, 42, 49, 56, 63, and 70 d), and ADG was calculated using a regression formed from BW taken every 14 d (0, 14, 28, 42, 56, and 70 d). Intervals for all traits were computed starting from both the beginning (day 0) and the end of the testing period (day 70). Pearson and Spearman correlations were computed for phenotypes from each shortened test period and for the full 70-d test. Minimum test duration was determined when the Pearson correlations were greater than 0.95 for each trait. Our results indicated that minimum test duration for WI, DMI, and ADG were 35, 42, and 70 d, respectively. No comparable studies exist for WI; however, our results for FI and ADG are consistent with those in the literature. Although further testing in other populations of cattle and areas of the country should take place, our results suggest that WI phenotypes can be collected concurrently with DMI, without extending test duration, even if following procedures for decoupled intake and gain tests.


Assuntos
Bovinos/fisiologia , Ingestão de Líquidos , Ingestão de Alimentos , Ração Animal , Animais , Dieta/veterinária , Masculino , Fenótipo , Distribuição Aleatória
19.
Acta Diabetol ; 55(5): 405-418, 2018 May.
Artigo em Inglês | MEDLINE | ID: mdl-29264724

RESUMO

Therapies to prevent diabetes in particular the progressive loss of ß-cell mass and function and/or to improve the dysregulated metabolism associated with diabetes are highly sought. The incretin-based therapy comprising GLP-1R agonists and DPP-4 inhibitors have represented a major focus of pharmaceutical R&D over the last decade. The incretin hormone GLP-1 has powerful antihyperglycemic effect through direct stimulation of insulin biosynthesis and secretion within the ß-cells; it normalizes ß-cell sensitivity to glucose, has an antiapoptotic role, stimulates ß-cell proliferation and differentiation, and inhibits glucagon secretion. However, native GLP-1 therapy is inappropriate due to the rapid post-secretory inactivation by DPP-4. Therefore, incretin mimetics developed on the backbone of the GLP-1 or exendin-4 molecule have been developed to behave as GLP-1R agonists but to display improved stability and clinical efficacy. New formulations of incretins and their analogs based on micro- and nanomaterials (i.e., PEG, PLGA, chitosan, liposomes and silica) and innovative encapsulation strategies have emerged to achieve a better stability of the incretin, to improve its pharmacokinetic profile, to lower the administration frequency or to allow another administration route and to display fewer adverse effects. An important advantage of these formulations is that they can also be used at the targeted non-invasive imaging of the beta-cell mass. This review therefore focuses on the current state of these efforts as the next step in the therapeutic evolution of this class of antidiabetic drugs.


Assuntos
Diabetes Mellitus Tipo 2/diagnóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Peptídeo 1 Semelhante ao Glucagon/fisiologia , Hipoglicemiantes/uso terapêutico , Células Secretoras de Insulina/patologia , Nanotecnologia/tendências , Animais , Diabetes Mellitus Tipo 2/metabolismo , Diabetes Mellitus Tipo 2/patologia , Inibidores da Dipeptidil Peptidase IV/uso terapêutico , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Humanos , Incretinas/metabolismo , Incretinas/uso terapêutico , Células Secretoras de Insulina/metabolismo , Microtecnologia/métodos , Nanotecnologia/métodos , Pâncreas/diagnóstico por imagem , Pâncreas/patologia
20.
Genes (Basel) ; 8(10)2017 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-29019931

RESUMO

Resistance gene analogs (RGAs) were searched bioinformatically in the sugar beet (Beta vulgaris L.) genome as potential candidates for improving resistance against different diseases. In the present study, Ion Torrent sequencing technology was used to identify mutations in 21 RGAs. The DNA samples of ninety-six individuals from six sea beets (Beta vulgaris L. subsp. maritima) and six sugar beet pollinators (eight individuals each) were used for the discovery of single-nucleotide polymorphisms (SNPs). Target amplicons of about 200 bp in length were designed with the Ion AmpliSeq Designer system in order to cover the DNA sequences of the RGAs. The number of SNPs ranged from 0 in four individuals to 278 in the pollinator R740 (which is resistant to rhizomania infection). Among different groups of beets, cytoplasmic male sterile lines had the highest number of SNPs (132) whereas the lowest number of SNPs belonged to O-types (95). The principal coordinates analysis (PCoA) showed that the polymorphisms inside the gene Bv8_184910_pkon (including the CCCTCC sequence) can effectively differentiate wild from cultivated beets, pointing at a possible mutation associated to rhizomania resistance that originated directly from cultivated beets. This is unlike other resistance sources that are introgressed from wild beets. This gene belongs to the receptor-like kinase (RLK) class of RGAs, and is associated to a hypothetical protein. In conclusion, this first report of using Ion Torrent sequencing technology in beet germplasm suggests that the identified sequence CCCTCC can be used in marker-assisted programs to differentiate wild from domestic beets and to identify other unknown disease resistance genes in beet.

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