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1.
J Dairy Sci ; 106(11): 7725-7736, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37641343

ABSTRACT

Automatic milking system (AMS) adoption in the United States is trending upward, with issues such as lower availability and increased cost of labor being factors frequently listed as motives for AMS implementation. In addition, more interest in precision dairy farming by the new generation of farmers may also help increase AMS adoption. The objective of this scoping review was to characterize the nature of the literature investigating non-pasture-based AMS and the opportunities and challenges for future research. The eligibility criteria included studies published in or after the year 2000, with full text in English, of at least 500 words, examining various outcomes related to AMS in non-pasture-based dairy farms. Six electronic databases were searched: Biosis (Web of Science), CAB Abstracts (CAB Direct), Medline (PubMed), PubAg, AGRIS (FAO), and Scopus (Elsevier). The review focused on studies with objectives, characteristics, farms, and AMS information. A total of 4,292 titles and abstracts were screened, and 536 studies were finally included. Most of the studies were conducted in Europe (73.5%), among commercial herds (67.9%), comprising Holstein cows (57.7%), using Lely and DeLaval brands (45.4% vs. 39.7%), with free-flow traffic (52.7%). The main research topics investigated were milk production, milk composition, and AMS efficiency, followed by behavior and welfare, health disorders (especially mastitis), and nutrition in Europe and other regions. At the same time, in the United States, trends were similar, except for nutrition. Since 2016, there has been an increased interest in studies on energy and water consumption, technological development, environment (enteric emissions), reproduction, genetics, and longevity or culling. However, the small number of studies and unclear characterization of what is optimum for reproductive management, other health disorders, economics, and water and energy consumption suggest a need for future research.

2.
J Dairy Sci ; 105(2): 1788-1796, 2022 Feb.
Article in English | MEDLINE | ID: mdl-34955251

ABSTRACT

The aim of this study was to document California, Idaho, South Dakota, and Washington dairy producers' perspectives on the health and business implications of COVID-19 during the pandemic second wave. Dairy producers were reached by a 14-question anonymous mail survey during June and July of 2020. We obtained 226 responses (response rate: 9.3% CA, 8.6% ID, 31.4%, and 10.0% WA). Responses were grouped by state (CA: 48.7%, ID: 15.9%, SD: 21.7%, or WA: 13.7%) and dairy size [based on number of cows; small (<100): 14.1%, medium (100-499): 27.7%, medium-large (500-1,999): 33.2%, or large (≥2,000): 25.0%]. Survey responses were summarized, and multiple correspondence analysis was used to map responses and identify data clusters. At the time of the survey, some respondents suspected (3%) or had confirmed (9%) COVID-19 cases on their premises. Respondents were somewhat or very concerned about the health (75%) and business (92%) implications associated with COVID-19. Producers were concerned about the health of their families, employees, and employees' families; having to reduce production; workforce shortage; limited goods availability; and lack of services. Producers perceived that their employees were somewhat or very concerned (74%) with the pandemic. There was COVID-19 safety information or training provided (78%) or intended (4%) in English (22%), Spanish (23%), or both (55%). The focus of training was as follows: how to remain healthy at work (91%) and at home (60%), what to do if a worker gets sick (77%), and sick leave information (54%). Nevertheless, 18% of the respondents answered that training was not going to be provided. The following control measures implemented: providing hand sanitizer or disinfectant wipes (78%), instruction on frequent hand-washing (76%), social distancing (59%), prevention of employee gatherings (54%), providing and requiring the use of face masks (49%), and limiting on-farm visitors (44%). Multiple correspondence analysis showed that concern with health risk and business impact of the COVID-19 pandemic, as well as mitigation and response strategies implemented, varied based on respondent's dairy size and state. The greatest concerns were reported by producers from California and large and medium-large dairies, whereas the fewest concerns were reported by producers from small dairies. Results from this survey highlighted the health and business concerns of dairy producers from California, Idaho, South Dakota, and Washington during the COVID-19 pandemic and the mitigation efforts adopted. In conclusion, mitigation measures were adopted by most dairy producers but in various degrees. Dairy industry service providers and educators were secondary educational resources during the pandemic; thus, future efforts toward centralized access to dairy specific bilingual educational materials are suggested.


Subject(s)
COVID-19 , Cattle Diseases , Animals , COVID-19/veterinary , California , Cattle , Dairying , Female , Idaho , Pandemics , SARS-CoV-2 , South Dakota , Washington
3.
J Dairy Sci ; 104(12): 12887-12899, 2021 Dec.
Article in English | MEDLINE | ID: mdl-34538497

ABSTRACT

The study's objectives were to identify cow-level and environmental factors associated with metritis cure to predict metritis cure using traditional statistics and machine learning algorithms. The data set used was from a previous study comparing the efficacy of different therapies and self-cure for metritis. Metritis was defined as fetid, watery, reddish-brownish discharge, with or without fever. Cure was defined as an absence of metritis signs 12 d after diagnosis. Cows were randomly allocated to receive a subcutaneous injection of 6.6 mg/kg of ceftiofur crystalline-free acid (Excede, Zoetis) at the day of diagnosis and 3 d later (n = 275); and no treatment at the time of metritis diagnosis (n = 275). The variables days in milk (DIM) at metritis diagnosis, treatment, season of the metritis diagnosis, month of metritis diagnostic, number of lactation, parity, calving score, dystocia, retained fetal membranes, body condition score at d 5 postpartum, vulvovaginal laceration score, the rectal temperature at the metritis diagnosis, fever at diagnosis, milk production from the day before to metritis diagnosis, and milk production slope up to 5, 7, and 9 DIM were offered to univariate logistic regression. Variables included in the multivariable logistic regression model were selected from the univariate analysis according to P-value. Variables were offered to the model to assess the association between these factors and metritis cure. Additionally, the univariate logistic regression variables were offered to a recursive feature elimination to find the optimal subset of features for a machine learning algorithms analysis. Cows without vulvovaginal laceration had 1.91 higher odds of curing of metritis than cows with vulvovaginal laceration. Cows that developed metritis at >7 DIM had 2.09 higher odds of being cured than cows that developed metritis at ≤7 DIM. For rectal temperature, each degree Celsius above 39.4°C led to lower odds to be cured than cows with rectal temperature ≤39.4°C. Furthermore, milk production slope and milk production difference from the day before to the metritis diagnosis were essential variables to predict metritis cure. Cows that had reduced milk production from the day before to the metritis diagnosis had lower odds to be cured than cows with moderate milk production increase. The results from the multivariable logistic regression and receiver operating characteristic analysis indicated that cows developing metritis at >7 DIM, with increase in milk production, and with a rectal temperature ≤39.40°C had increased likelihood of cure of metritis with an accuracy of 75%. The machine learning analysis showed that in addition to these variables, calving-related disorders, season, and month of metritis event were needed to predict whether the cow will cure or not from metritis with an accuracy ≥70% and F1 score (harmonic mean between precision and recall) ≥0.78. Although machine learning algorithms are acknowledged as powerful tools for predictive classification, the current study was unable to replicate its potential benefits. More research is needed to optimize predictive models of metritis cure.


Subject(s)
Cattle Diseases , Endometritis , Algorithms , Animals , Cattle , Cattle Diseases/diagnosis , Cattle Diseases/therapy , Endometritis/diagnosis , Endometritis/veterinary , Female , Lactation , Machine Learning , Milk , Postpartum Period , Pregnancy , Reproduction
4.
J Dairy Sci ; 103(8): 7555-7568, 2020 Aug.
Article in English | MEDLINE | ID: mdl-32534930

ABSTRACT

Records of late-gestation heat stress studies conducted over 10 consecutive years in Florida were pooled and analyzed to test the hypothesis that maternal hyperthermia during late gestation impairs performance of the offspring across multiple generations and lactations, ultimately impeding the profitability of the US dairy sector. Dry-pregnant multiparous dams were actively cooled (CL; shade of a freestall barn, fans and water soakers, n = 196) or not (HT; shade only, n = 198) during the last 46 d of gestation, concurrent with the entire dry period. After data mining, records of 156 daughters (F1) that were born either to CL (CLF1, n = 77) or HT dams (HTF1, n = 79) and 45 granddaughters (F2) that were born either to CLF1 (CLF2, n = 24) or HTF1 (HTF2, n = 21) were used in the analysis. Life events and daily milk yield for 3 lactations of daughters and granddaughters were obtained. Milk yield, reproductive performance, and productive life data were analyzed using MIXED and GLIMMIX procedures, and lifespan was analyzed using PHREG and LIFETEST procedures of SAS (SAS Institute Inc., Cary, NC). Milk production of HTF1 was reduced in their first (2.2 kg/d), second (2.3 kg/d), and third lactations (6.5 kg/d) compared with CLF1. More HTF1 were culled before first calving, and the productive life and lifespan of HTF1 were reduced relative to CLF1 (4.9 and 11.7 mo, respectively). The granddaughters (HTF2) born to HTF1 produced less milk in their first lactation (1.3 kg/d) relative to granddaughters (CLF2) born to CLF1. More HTF2 were culled before first breeding relative to CLF2; however, productive life and lifespan were not different between HTF2 and CLF2 animals. An economic analysis was then performed based on the number of heat stress days, dry cows per state, and the aforementioned impairments on daughters' lifespans and milk production. Collectively in the United States, the economic losses for additional heifer rearing cost, reduced productive life, and reduced milk yield of the F1 offspring were estimated at $134, $90, and $371 million per year, respectively. In summary, late-gestation heat stress exerts carryover effects on at least 2 generations. Providing heat abatement to dry-pregnant dams is important to rescue milk loss of the dam and to prevent losses in their progeny.


Subject(s)
Cattle Diseases/etiology , Dairying , Heat Stress Disorders/veterinary , Heat-Shock Response , Pregnancy Complications/veterinary , Prenatal Exposure Delayed Effects/veterinary , Animals , Cattle , Female , Florida , Health Status , Lactation , Milk , Parturition , Pregnancy , Reproduction
5.
J Eur Acad Dermatol Venereol ; 32(8): 1272-1277, 2018 Aug.
Article in English | MEDLINE | ID: mdl-29220543

ABSTRACT

BACKGROUND AND OBJECTIVES: Primary skin cancer prevention campaigns are essential and more effective among children, not only because of the importance of sun exposure effects during this period, but also because this age is when individuals are developing behaviours. The Brazilian Society of Dermatology - Regional State of Sao Paulo developed and conducted the programme named 'The Sun, Friend of Childhood', a school health education and disease prevention project for children and parents. Our objective was to evaluate the cognitive and behavioural effects of the children and parents before and after an education model-based intervention of sun protection. METHODS: We carried out a study on a school population of Social Service of Industry - Regional State of São Paulo, from the first to the fifth years of the regular course (6-10 years). Our educational project was planned to be based on two children's learning tools (comic magazine and a DVD cartoon). Questionnaires in relation to habits and knowledge in sun exposure were applied to the children (3776) before and (2748) after the intervention. A questionnaire was applied to 3663 parents regarding personal details and habits of their children. RESULTS: According to the McNemar's statistical test, all changes in the children in acquiring new knowledge about good practices for sun exposure were statistically significant. CONCLUSIONS: Educative sun exposure programmes in childhood are a relevant tool to modify the history of life for next generations, to concern the skin cancer and good health practices.


Subject(s)
Health Behavior , Health Education/methods , Health Knowledge, Attitudes, Practice , Skin Neoplasms/prevention & control , Adolescent , Brazil , Cartoons as Topic , Child , Child, Preschool , Cognition , Humans , Parents , Program Evaluation , Schools , Sunlight/adverse effects , Surveys and Questionnaires
6.
J Dairy Sci ; 99(12): 9931-9941, 2016 Dec.
Article in English | MEDLINE | ID: mdl-27743663

ABSTRACT

Heat stress during the dry period reduces milk yield in the subsequent lactation of dairy cows. Our objectives were to quantify the economic losses due to heat stress if dry cows are not cooled and to evaluate the economic feasibility of dry cow cooling. We used weather data from the National Oceanic and Atmospheric Administration to calculate the number of heat stress days for each of the 50 US states. A heat stress day was declared when the daily average temperature-humidity index was ≥68. The number of dairy cows in each state in 2015 was obtained from the USDA-National Agricultural Statistics Service. We assumed that 15% of the cows were dry at any time, a 60-d dry period, and a calving interval of 400d. Only cows in their second or greater parity (65%) benefitted from cooling during the dry period of the previous parity. Milk yield decreased by 5kg in the subsequent lactation (340d) if the cow experienced heat stress during the dry period based on a review of the literature. The default marginal value of milk minus feed cost was $0.33/kg of milk. The investment analysis included purchases of fans and soakers and use of water and electricity. Investment in a dry cow barn was considered separately. The average US dairy cow would experience 96 (26%) heat stress days during the year if not cooled and loses 447kg of milk in the subsequent lactation if not cooled when dry. Annual losses would be $810 million if dry cows were not cooled ($87/cow per yr). For the top 3 milk-producing states (California, Wisconsin, New York), and Florida and Texas, the average milk losses in the subsequent lactation were 522, 349, 387, 1,197, and 904kg, and reduced profit per cow per year would be $101, $68, $75, $233, and $176, respectively. The average benefit-cost ratio and payback periods of cooling dry cows in the United States were 3.15 and 0.27 yr (dry cow barn already present) and 1.45 and 5.68 yr (if investing in a dry cow barn) in the default scenario. To reach positive net present values, 6d (barn is present) and 55d (barn investment necessary) of heat stress annually were necessary (default assumptions). Other benefits of cooling, such as increased health and more productive offspring, were not considered. In conclusion, cooling of dry cows was profitable for 89% of the cows in the United States when building a new barn is required (under default assumptions) and very profitable when construction of a dry cow barn is not required (except for Alaska).


Subject(s)
Cattle Diseases/economics , Cattle Diseases/prevention & control , Heat Stress Disorders/veterinary , Milk/economics , Animals , Cattle , Cold Temperature , Feasibility Studies , Female , Heat Stress Disorders/economics , Heat Stress Disorders/prevention & control , Lactation , Milk/metabolism , United States
7.
Int J Sports Med ; 37(11): 841-8, 2016 Oct.
Article in English | MEDLINE | ID: mdl-27428645

ABSTRACT

Estrogen reduction is associated with a decline in skeletal muscle mitochondrial biogenesis. Molecular events associated with improvements in markers of mitochondrial biogenesis after resistance training and estradiol replacement are unknown. This study aimed to investigate the effects of ovariectomy, resistance training, and estradiol replacement on markers of mitochondrial biogenesis and protein expression related to oxidative capacity in the rat gastrocnemius pool. Estradiol replacement was performed using Silastic(®) capsules. During the 12-week resistance training, animals climbed a ladder with weights attached to their tails. Gene expression was analysed by RT-PCR, and protein content was determined by western blotting. Ovariectomy decreased the gene expression of the mitochondrial biogenesis markers PGC-1α (~73%), NRF-1 (~44%), and TFAM (~53%) (p<0.05) and decreased the protein expression of phosphorylated AMPK, CREB and AKT, which are related to oxidative capacity. Resistance training increased PGC-1α (~59%) and TFAM (~48%) expression compared to the Ovariectomy-Sedentary group. The combination of resistance training and estradiol replacement was superior to the ovariectomy-sedentary and ovariectomy-resistance training treatments regarding the gastrocnemius muscle. Estrogen deficiency altered the expression of genes and proteins that favour the development of a mitochondrial dysfunction phenotype, which was improved with resistance training and was partially improved by estradiol replacement.


Subject(s)
Muscle, Skeletal/physiology , Organelle Biogenesis , Physical Conditioning, Animal/physiology , Resistance Training , Animals , Blotting, Western , Estradiol/administration & dosage , Estrogens/deficiency , Female , Gene Expression Regulation/physiology , Ovariectomy , Rats , Reverse Transcriptase Polymerase Chain Reaction , Sedentary Behavior
8.
J Dairy Sci ; 98(6): 4182-97, 2015 Jun.
Article in English | MEDLINE | ID: mdl-25795483

ABSTRACT

Dairy farms in Florida produce less milk and milk with higher somatic cell counts (SCC) in the hot and humid summer. This has consequences for the interpretation of average milk quality. The objectives were to describe the associations of bulk tank SCC (BTSCC) with time of the year and the milk volume per farm. Monthly BTSCC and milk volume records from 84% (in 2012; n=1,308) and 77% (in 2013; n=1,200) of the 130 dairy farms in Florida were used. Data were analyzed separately per year. We calculated arithmetic averages of the BTSCC for each farm (ASCCf), each month (ASCCm), and each year (ASCCy). We used the milk volume to calculate a milk-weighted average for each farm (WSCCf), each month (WSCCm), and each year (WSCCy). Period 1 (P1) was defined as February, March, and April, and period 2 (P2) was defined as August, September, and October. These periods generally had the lowest and highest BTSCC throughout the year, respectively. Seasonality was expressed by the P2/P1 ratios of BTSCC and milk volume in both periods. In 2012 and 2013, 72 and 74% of the monthly milk volume observations were <400,000cells/mL. A clear seasonal pattern with lower milk volume and higher ASCCm during P2 was observed for most farms. The averages of the P2/P1 ratio of milk volume were 0.68 and 0.74 in 2012 and 2013. The averages of the P2/P1 ratio of SCC were 1.30 and 1.65 for 2012 and 2013, respectively. The WSCCy was 297,000 cells/mL in 2012 and 274,000 cells/mL in 2013. These values were 13 and 16% lower than the ASCCy in the respective years. In 2012, 82% of the farms shipped milk with a lower WSCCf than their ASCCf. In 2013, 97% of the farms shipped milk with a lower WSCCf than their ASCCf. The difference between a farm's WSCCf and its ASCCf tended to be greater in more-seasonal farms for BTSCC and milk volume. The WSCCm was lower than the ASCCm in every calendar month in both years. Collectively, these results show that the SCC of pooled milk from Florida was substantially lower than the arithmetic averages of monthly BTSCC values. Therefore, it should be made clear if the SCC is weighted by milk volume when "average" SCC results are reported. Programs to improve milk quality in Florida might be focused on conditions during August, September, and October because the BTSCC is then markedly increased on many farms.


Subject(s)
Cell Count/veterinary , Dairying , Milk/chemistry , Animals , Florida , Seasons
9.
Res Vet Sci ; 171: 105225, 2024 May.
Article in English | MEDLINE | ID: mdl-38507827

ABSTRACT

This retrospective cohort study aimed to identify risk factors for the failure of transfer of passive immunity (FPI) in preweaned dairy calves, explore its associations with morbidity, mortality, genetics, and determine a standardized cut-off point for FPI. Analyzing data from 6011 calves, factors such as sire predicted transmitted ability for milk (PTA), birth season, retained placenta (RP), total serum protein concentration (TSP), morbidity (neonatal calf diarrhea - NCD, bovine respiratory disease - BRD, tick-borne disease - TBD), mortality, and average daily weight gain (ADG) were considered. The calves were categorized into predominantly Gyr (PG) and predominantly Holstein (PH) genetic composition groups. Multivariate mixed logistic regression revealed optimal TSP cut-off points for predicting morbidity (7.6 g/dL) and mortality (6.9 g/dL). PH calves exhibited 1.35 times higher odds of FPI and 1.48 times greater odds of disease. Calves from multiparous cows and those born to dams with RP had increased FPI odds. Disease prevalence was 53%, with 41% NCD, 18% BRD, and 10% TBD. Season, parity, PTA, and birth weight were associated with disease odds, though FPI was not a reliable predictor. The mortality percentage was 6%, with PH calves and those with a positive PTA having higher odds. The ADG was 0.64 kg, and FPI-affected calves gained less weight. The study compared and identified various risk factors that potentially impact calf immunity. However, the use of a standardized cut-off point for FPI assessment was not effective in predicting morbidity and mortality at this specific farm.


Subject(s)
Cattle Diseases , Noncommunicable Diseases , Humans , Pregnancy , Female , Animals , Cattle , Noncommunicable Diseases/veterinary , Retrospective Studies , Cattle Diseases/epidemiology , Cattle Diseases/genetics , Milk , Risk Factors
10.
Braz J Med Biol Res ; 57: e13309, 2024.
Article in English | MEDLINE | ID: mdl-38656073

ABSTRACT

Diabetic-metabolic syndrome (MetS-D) has a high prevalence worldwide, in which an association with the rupture of the intestinal epithelium barrier function (IEBF) has been pointed out, but the functional and morphological properties are still not well understood. This study aimed to evaluate the impact of acute hyperglycemia diabetes on intestinal tight junction proteins, metabolic failure, intestinal ion and water transports, and IEBF parameters. Diabetes was induced in male Rattus norvegicus (200-310 g) with 0.5 mL of streptozotocin (70 mg/kg). Glycemic and clinical parameters were evaluated every 7 days, and intestinal parameters were evaluated on the 14th day. The MetS-D animals showed a clinical pattern of hyperglycemia, with increases in the area of villi and crypts, lactulose:mannitol ratio, myeloperoxidase (MPO) activity, and intestinal tissue concentrations of malondialdehyde (MDA), but showed a reduction in reduced glutathione (GSH) when these parameters were compared to the control. The MetS-D group had increased secretion of Na+, K+, Cl-, and water compared to the control group in ileal tissue. Furthermore, we observed a reduction in mRNA transcript of claudin-2, claudin-15, and NHE3 and increases of SGLT-1 and ZO-1 in the MetS-D group. These results showed that MetS-D triggered intestinal tissue inflammation, oxidative stress, complex alterations in gene regulatory protein transcriptions of intestinal transporters and tight junctions, damaging the IEBF and causing hydroelectrolyte secretion.


Subject(s)
Diabetes Mellitus, Experimental , Hyperglycemia , Intestinal Mucosa , Tight Junctions , Animals , Male , Intestinal Mucosa/metabolism , Intestinal Mucosa/pathology , Diabetes Mellitus, Experimental/metabolism , Hyperglycemia/metabolism , Tight Junctions/metabolism , Rats , Inflammation/metabolism , Disease Models, Animal , Rats, Wistar , Metabolic Syndrome/metabolism , Metabolic Syndrome/physiopathology
11.
JDS Commun ; 4(3): 186-190, 2023 May.
Article in English | MEDLINE | ID: mdl-36811073

ABSTRACT

Our objective was to understand dairy employees' perceptions and educational needs at the onset of the COVID-19 pandemic. A bilingual (English and Spanish), anonymous survey targeted at dairy employees was circulated nationwide via university and allied industry media outlets. Responses (n = 63) from 11 states were received (May-Sep. 2020). Respondents worked in herds ranging from 50 to 40,000 animals in size. Dairy managers (33%) responded mostly to the English survey (52%), whereas entry-level workers (67%) chose the Spanish format (76%). Survey results highlighted different perspectives, educational needs, and preferred sources of information between English- and Spanish-speaking dairy workers. Overall, 83% of the respondents were somewhat concerned or very concerned about the COVID-19 pandemic. Respondents (51%) indicated that their main concern was "to bring the virus from work to home and make my family sick." Most dairy employees (83%) perceived that their employers were somewhat or very concerned about the pandemic. Respondents (65%) indicated that COVID-19 informative training was provided at the workplace, but training was more frequently undertaken among dairy managers (86%) than entry-level workers (53%). Most trainings (72%) were limited to posters on walls. The preferred means of information delivery was through in-person meetings at work (35%), with YouTube (29%) and on-demand videos (27%) as second and third options. The main source of information regarding the pandemic was social media (52%). Frequent handwashing (81%), limiting on-farm visits (70%), limiting agglomeration in break rooms (65%), hand sanitizer use (60%), and social distancing (60%) were the most common safety measures implemented at the workplace among the options given to respondents. Few respondents (38%) indicated that face-covering was required at work. Successful emergency plans on dairies should consider the outreach needs and preferences of dairy workers.

12.
Rev Gastroenterol Mex ; 77(1): 31-7, 2012.
Article in Spanish | MEDLINE | ID: mdl-22450018

ABSTRACT

Ultrasound-guided biliary drainage is a new and effective method for relieving obstructive lesions of the biliary tract. In the hands of experienced operators, ultrasound-guided diversion of the mid portion of the common bile duct and the duodenal bulb is a feasible strategy for the relief of jaundice secondary to distal obstruction (distal bile duct tumors, pancreatic head cancer, or major duodenal papillary tumor), with low morbidity and mortality rates. The technical aspects of the procedure and its indications are reviewed herein, emphasizing its performance in institutions equipped with experienced personnel adhering to strict study protocols.


Subject(s)
Choledochostomy/methods , Cholestasis/surgery , Endosonography , Cholestasis/etiology , Humans
13.
Biomater Sci ; 10(20): 5856-5875, 2022 Oct 11.
Article in English | MEDLINE | ID: mdl-36047651

ABSTRACT

Osteochondral (OC) defects combine damage to cartilage and subchondral bone, posing a significant challenge to their repair due to the dissimilar characteristics and regenerative capabilities between the two tissues. Here, we propose novel OC bilayer composites, drawing inspiration from corresponding biological tissues and using a combination of simple and reproducible techniques. Cartilage-like materials based on poly(vinyl alcohol) (PVA) hydrogels were produced with nanofiber reinforcements acquired from high-performance fibers (Kevlar® and Zylon®), while bone-like materials were obtained by adding magnesium-substituted calcium phosphate ceramics to PVA. All composites were sterilized by gamma irradiation to rule out the possibility of undesirable effects resulting from the process, and then fully characterized. The results indicated that nanofibers and bioceramics incorporated into the PVA networks form promising structures with multiple interesting properties. The composites resembling cartilage and bone showed high biomimicry with natural tissues, being able to reconcile exceptional mechanics with the requirements of adequate porosity, liquid content, and biological behavior. The developed materials reveal a high potential for use in OC tissue repair applications.


Subject(s)
Cartilage, Articular , Polyvinyl Alcohol , Calcium Phosphates , Cartilage , Hydrogels/chemistry , Magnesium , Polyvinyl Alcohol/chemistry , Tissue Engineering/methods , Tissue Scaffolds/chemistry
14.
Animal ; 15(2): 100117, 2021 Feb.
Article in English | MEDLINE | ID: mdl-33573948

ABSTRACT

The use of embryo transfer helps to improve reproductive performance during periods of heat stress. In vitro produced embryo transfer (IVP-ET) is more expensive than artificial insemination. We hypothesized that the value IVP-ET in seasonal herds depends on herd constraints, such as the maximum number of milking cows and the maximum number of calvings that can be accommodated throughout the year. Therefore, the objective of this study was to estimate how profitability in dairy herds exposed to summer heat stress is affected by the number of months in which IVP-ET is used, the use of IVP-ET in repeat-breeder cows, IVP-ET cost, and herd constraints. We built and used a nonlinear programming model of a dairy herd with young stock and cows with monthly Markov Chain transitions. The model varied the number of heifers calving in each calendar month to maximize herd profitability. We varied IVP-ET cost ($100 or $200), duration of the IVP-ET program (2 or 4 months), and the breeding number in which IVP-ET started (1st or 3rd). In total, 20 scenarios were simulated. Maximum profitability was obtained when IVP-ET was not used, regardless of herd constraints. The 16 scenarios in which IVP-ET was used showed increased seasonality in milk yield, numbers of milking cows, total cows, total calvings, and heifer calvings because the program tried to limit the number of IVP-ET breedings in the summer. The addition of the calving constraint increased the value of IVP-ET. The breakeven cost per IVP-ET ranged from -$6.79 to $24.38 compared with conventional semen cost of $20. In conclusion, the current market costs of IVP-ET did not warrant application with the objective to increase reproductive performance during heat stress. Herd constraints on the maximum allowable seasonality in the monthly number of milking cows and calvings affected the value of IVP-ET during heat stress.


Subject(s)
Insemination, Artificial , Lactation , Animals , Cattle , Dairying , Embryo Transfer/veterinary , Female , Heat-Shock Response , Insemination, Artificial/veterinary , Milk
15.
Spectrochim Acta A Mol Biomol Spectrosc ; 233: 118198, 2020 Jun 05.
Article in English | MEDLINE | ID: mdl-32179440

ABSTRACT

In this work, the natural flower extracted dyes containing luteolin were prepared using three different specimens from daisy flowers family (Leucanthemum vulgare), namely yellow daisy, purple daisy and wine daisy, according to the color of its petals. Moreover, DSSCs were fabricated using nanosized titanium dioxide (TiO2) as an anode; for the photocathodes, two different specimens were used: i) graphite electrode and ii) platinum electrode. To recognize the light absorption behavior, the existence of anchoring groups and coloring components of the extracted dyes were determined using absorption spectroscopy. The surface roughness of the photoanodes and cathodes were examined using atomic force microscope (AFM). The photovoltaic performance and efficiency of assembled DSSCs were evaluated to realize the influence of TiO2 photoanodes on interaction of the Leucanthemum vulgare extracted dye molecules with graphite or platinum photocathodes. DSSCs fabricated with platinum cathode show higher conversion efficiency (η) of 0.6%, 0.4% and 0.8% for the yellow daisy, wine daisy and purple daisy, respectively. DSSCs sensitized with daisy wine dye showed highest open-circuit voltage (Voc) of 520 mV and efficiency of 0.79% and 0.88%, for the graphite and platinum cathodes, respectively. These results showed that the DSSCs, using daisy flowers extracts as efficient photosensitizers, are suitable for the fabrication of environmentally safe, inexpensive, clean and renewable energy.


Subject(s)
Asteraceae/chemistry , Electric Power Supplies , Flowers/chemistry , Pigments, Biological , Solar Energy , Electrodes , Pigments, Biological/chemistry , Pigments, Biological/isolation & purification , Titanium/chemistry
16.
Sci Total Environ ; 740: 140237, 2020 Oct 20.
Article in English | MEDLINE | ID: mdl-32927553

ABSTRACT

Thirty people (mostly children) experienced an episode of skin rash days after a sand sifting beach operation at Porto Pim Beach in Faial, Azores during June 2019. An environmental and epidemiologic investigation was conducted to identify the cause of the outbreak of skin rash. The epidemiologic investigation found that some of the patients experiencing symptoms had never entered the beach water. During the pollution period and throughout the epidemiologic investigation, faecal indicator bacteria levels (94 CFU/100 ml for intestinal enterococci and 61 CFU/100 ml for Escherichia coli) in water remained under the limits used for the ninety-five percentile calculation of an Excellent coastal and transitional bathing water defined in the Portuguese Legislation (100 CFU/100 ml for intestinal enterococci and 250 CFU/100 ml for Escherichia coli). Thus sand contact was considered as a likely primary exposure route. Sand microbiological analysis for faecal indicator organisms and electron microscopy strongly suggested faecal contamination. Chemical analysis of the sand also revealed a concomitant substance compatible with sodium-hypochlorite as analysed using gas chromatography and subsequently confirmed by free chlorine analysis. Inspection of the toilet facilities and sewage disposal system revealed a leaking sewage distribution box. Collectively, results suggest that the cause of the outbreak was the leaking underground sewage distribution box that serviced the beach toilet facilities (40 m from beach), where sodium-hypochlorite was used for cleaning and disinfection. This sewage then contaminated the surficial sands to which beach goers were exposed. Chlorine being an irritant substance, was believed to have been the cause of the symptoms given the sudden presentation and dissipation of skin rashes. No gastro-intestinal illness was reported during this episode and during the following 30 days. Like water, beach sand should also be monitored for safety, especially for areas serviced by aged infrastructure.


Subject(s)
Bathing Beaches , Sewage , Azores , Child , Environmental Monitoring , Feces , Humans , Sand , Water Microbiology
17.
AJNR Am J Neuroradiol ; 41(1): 174-177, 2020 01.
Article in English | MEDLINE | ID: mdl-31806601

ABSTRACT

Since 2005, it has been known that mother-to-child transmission of the chikungunya virus is possible. Transmission generally occurs in the perinatal period. In the present study, we describe the brain lesions seen on MR imaging of 6 cases of perinatal chikungunya infection. Patients who underwent brain MR imaging in the acute phase presented with areas of restricted diffusion in the white matter, suggesting a perivascular distribution, whereas those in the subacute/late phase showed cystic lesions, also with a perivascular distribution, with or without brain atrophy. One patient also presented with scattered hemorrhages in the frontal and parietal lobes. Important differential diagnoses include rotavirus, Parechovirus, herpes simplex infection, and hypoxic-ischemic encephalopathy, depending on the disease phase.


Subject(s)
Brain/diagnostic imaging , Chikungunya Fever/congenital , Chikungunya Fever/diagnostic imaging , Atrophy/pathology , Brain/pathology , Chikungunya Fever/transmission , Female , Humans , Infant, Newborn , Infectious Disease Transmission, Vertical , Magnetic Resonance Imaging/methods , Male , Neuroimaging/methods , Pregnancy
18.
Retrovirology ; 6: 39, 2009 Apr 22.
Article in English | MEDLINE | ID: mdl-19386115

ABSTRACT

BACKGROUND: Here, we investigated the phylogenetic relationships of the HIV-1 subtype F1 circulating in Angola with subtype F1 strains sampled worldwide and reconstructed the evolutionary history of this subtype in Central Africa. METHODS: Forty-six HIV-1-positive samples were collected in Angola in 2006 and subtyped at the env-gp41 region. Partial env-gp120 and pol-RT sequences and near full-length genomes from those env-gp41 subtype F1 samples were further generated. Phylogenetic analyses of partial and full-length subtype F1 strains isolated worldwide were carried out. The onset date of the subtype F1 epidemic in Central Africa was estimated using a Bayesian Markov chain Monte Carlo approach. RESULTS: Nine Angolan samples were classified as subtype F1 based on the analysis of the env-gp41 region. All nine Angolan sequences were also classified as subtype F1 in both env-gp120 and pol-RT genomic regions, and near full-length genome analysis of four of these samples confirmed their classification as "pure" subtype F1. Phylogenetic analyses of subtype F1 strains isolated worldwide revealed that isolates from the Democratic Republic of Congo (DRC) were the earliest branching lineages within the subtype F1 phylogeny. Most strains from Angola segregated in a monophyletic group together with Romanian sequences; whereas South American F1 sequences emerged as an independent cluster. The origin of the subtype F1 epidemic in Central African was estimated at 1958 (1934-1971). CONCLUSION: "Pure" subtype F1 strains are common in Angola and seem to be the result of a single founder event. Subtype F1 sequences from Angola are closely related to those described in Romania, and only distantly related to the subtype F1 lineage circulating in South America. Original diversification of subtype F1 probably occurred within the DRC around the late 1950s.


Subject(s)
HIV Infections/virology , HIV-1/classification , HIV-1/genetics , Phylogeny , Angola , Human Immunodeficiency Virus Proteins/genetics , Humans , Molecular Sequence Data , Romania , Time Factors
19.
Braz. j. med. biol. res ; 57: e13309, fev.2024. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1557314

ABSTRACT

Abstract Diabetic-metabolic syndrome (MetS-D) has a high prevalence worldwide, in which an association with the rupture of the intestinal epithelium barrier function (IEBF) has been pointed out, but the functional and morphological properties are still not well understood. This study aimed to evaluate the impact of acute hyperglycemia diabetes on intestinal tight junction proteins, metabolic failure, intestinal ion and water transports, and IEBF parameters. Diabetes was induced in male Rattus norvegicus (200-310 g) with 0.5 mL of streptozotocin (70 mg/kg). Glycemic and clinical parameters were evaluated every 7 days, and intestinal parameters were evaluated on the 14th day. The MetS-D animals showed a clinical pattern of hyperglycemia, with increases in the area of villi and crypts, lactulose:mannitol ratio, myeloperoxidase (MPO) activity, and intestinal tissue concentrations of malondialdehyde (MDA), but showed a reduction in reduced glutathione (GSH) when these parameters were compared to the control. The MetS-D group had increased secretion of Na+, K+, Cl-, and water compared to the control group in ileal tissue. Furthermore, we observed a reduction in mRNA transcript of claudin-2, claudin-15, and NHE3 and increases of SGLT-1 and ZO-1 in the MetS-D group. These results showed that MetS-D triggered intestinal tissue inflammation, oxidative stress, complex alterations in gene regulatory protein transcriptions of intestinal transporters and tight junctions, damaging the IEBF and causing hydroelectrolyte secretion.

20.
Braz J Biol ; 67(1): 23-32, 2007 Feb.
Article in English | MEDLINE | ID: mdl-17505746

ABSTRACT

The effect of anthropic alterations such as drain discharge on a fish community was studied in the Ribeirão Claro River, municipality of Rio Claro, State of São Paulo, southeastern Brazil. Samples were made monthly in three different points along the river (headwaters, mid course, and confluence) between December, 2003 and March, 2004, which is the reproductive period for the majority of the species. The fish community of the Ribeirão Claro River showed a fair composition and diversity, with species rarely observed in studies made in the region, such as Paravandellia oxyfera and Callichthys callichthys. Indices of diversity and equitability showed different results when weight or the number of individuals were considered. Moreover, these indices did not reveal the typical increase in diversity from the headwaters toward the confluence, nor the loss of richness in the part altered by drain discharge. An interpretation should be made with caution, taking into account the diverse factors included in the computation. Similar to the diversity indices, the Morisita-Horn similarity index did not reveal a great difference in the fish community of the confluence of the river, mainly in relation to its mid course. The decline of species richness and trophic composition alteration in the disturbed part is clear, which shows a great dominance of piscivorous species.


Subject(s)
Biodiversity , Environmental Monitoring , Fishes/classification , Rivers/chemistry , Sewage/adverse effects , Animals , Brazil , Fishes/physiology , Population Density
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