Risk factors associated to retained placenta in Holstein cows

Background: Retained placenta (RP) is characterized by a failure to remove the fetal membranes within the first 12-24 h after calving. This condition appears to be related to a decrease in neutrophil activity and to the suppression of the immune response in the prepartum period. The specific reasons for some cows to retain the placenta after parturition is still not fully understood, but numerous predisposing factors have been related, which may include mechanical, nutritional, infectious and handling factors. The aim of this study was to analyze the occurrence of retained placenta in dairy cows and to correlate the main predisposing factors related. Materials, Methods & Results: This study was conducted in nine dairy farms located in the Rio Grande do Sul state, Brazil, with an average of 45 lactating dairy cows producing 10,100 kg / dairy cow in a period of 305 days. The total diet for postpartum cows was estimated to meet or exceed the requirements of dairy cows according to previously established guidelines (NRC 2001). A total of 393 calving Holstein cows (126 primiparous and 267 multiparous) were analyzed, of which 203 were kept in a semi-confined production system (free-stall and pasture system) and 190 animals were kept in a free-stall production system. Statistically, the cows were the experimental unit, and the results were analyzed using the Pearson’s Chi-squared test or Fisher’s exact test for the comparisons of occurrence of peripartum disorders. In addition, linear and logistic regression models were constructed to determine the effect of the dependent variable on the other indicators, which may be continuous or categorical. Possible correlations of the occurrence of peripartum disorders related to production system (free-stall or semi-confined), calving order (primiparous or multiparous), season of the year (heat or cold), ECC at calving (1 to 5), calf sex, rectal temperature and dystocia were analyzed. Of the 393 deliveries followed up in this study, 72 presented retained placenta as a postpartum complication. Cows that delivered male calves had a 3.45 times higher chance of presenting dystocia birth (P = 0.0007) and had 1.85 times more chances of presenting placental retention (P = 0.066) when compared to cows with female calves. Cows with dystocia were more likely to present RP (P = 0.0433). Twin pregnancies increased 3.9 times chances of RP (P = 0.0193). Discussion: The incidence of RP in our study was 18.3%, which is close to the previously reported by another Brazilian study (22%) and similar to another study that also verified the risk factor indicators (19.9%). Dystocia, twin births and male births were predisposing factors for RP, similarly to previous studies. The frequency of dystocia was significantly affected by the production system employed, with the semi-confined system presenting more cases of dystocia, unlike other studies. The season of the year had no influence in the RP occurrence, unlike other studies that showed RP may have an increase in spring and summer months. A possible correlation between RP and body condition score at calving and with the production system employed was not observed. The limited options of effective treatments for RP emphasizes the importance of prevention. RP prevention includes the reduction of stressful factors, especially in the peripartum period, with a focus one nutrition and animal health

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear un derstanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5–7 vast areas of the tropics remain understudied.8–11 In the American tropics, Amazonia stands out as the world’s most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepre sented in biodiversity databases.13–15 To worsen this situation, human-induced modifications16,17 may elim inate pieces of the Amazon’s biodiversity puzzle before we can use them to understand how ecological com munities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple or ganism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region’s vulnerability to environmental change. 15%–18% of the most ne glected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lostinfo:eu-repo/semantics/publishedVersio

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Pervasive gaps in Amazonian ecological research

Biodiversity loss is one of the main challenges of our time,1,2 and attempts to address it require a clear understanding of how ecological communities respond to environmental change across time and space.3,4 While the increasing availability of global databases on ecological communities has advanced our knowledge of biodiversity sensitivity to environmental changes,5,6,7 vast areas of the tropics remain understudied.8,9,10,11 In the American tropics, Amazonia stands out as the world's most diverse rainforest and the primary source of Neotropical biodiversity,12 but it remains among the least known forests in America and is often underrepresented in biodiversity databases.13,14,15 To worsen this situation, human-induced modifications16,17 may eliminate pieces of the Amazon's biodiversity puzzle before we can use them to understand how ecological communities are responding. To increase generalization and applicability of biodiversity knowledge,18,19 it is thus crucial to reduce biases in ecological research, particularly in regions projected to face the most pronounced environmental changes. We integrate ecological community metadata of 7,694 sampling sites for multiple organism groups in a machine learning model framework to map the research probability across the Brazilian Amazonia, while identifying the region's vulnerability to environmental change. 15%–18% of the most neglected areas in ecological research are expected to experience severe climate or land use changes by 2050. This means that unless we take immediate action, we will not be able to establish their current status, much less monitor how it is changing and what is being lost

Utilização de dietas aniônicas como prevenção de hipocalcemia em vacas de leite

Durante o período pós-parto, as vacas de leite têm um elevado risco de desenvolver doenças metabólicas que prejudicam a produção de leite e desempenho reprodutivo subsequente. Muitas dessas doenças são resultados do manejo nutricional inadequado durante o período seco. Pelo fato das vacas secas não contribuem para a produção de leite, muitos produtores ignoram esses animais, e as suas necessidades nutricionais são comprometidos. Veterinários devem convencer os produtores de leite que o período seco é uma fase preparatória para a próxima lactação e que vacas secas são um investimento para a próxima lactação. Vacas de leite do período de transição do pré-parto devem ser manejadas e alimentadas para que no dia do parto e início da lactação as vacas estejam fisiologicamente preparadas para fazer os ajustes necessários nas demandas de cálcio e energia. A hipocalcemia ocorre mais comumente neste período e pode levar a uma redução no consumo de matéria seca (CMS) depois do parto, maior risco de doenças secundárias, diminuição da produção de leite e redução da fertilidade. Portanto, este trabalho tem o objetivo de analisar as estratégias de controle da hipocalcemia puerperal, enfatizando aspectos do manejo nutricional, com base na literatura sobre o assunto.During the postpartum period, dairy cows are at a high risk to develop metabolic diseases that impair milk production and subsequent reproductive performance. Many of these diseases are the result of improper nutritional management during the dry period. Because dry cows not contribute to the milk check, many producers ignore these animals, and their nutritional needs are compromised. Veterinarians must convince dairy producers that the dry period is a preparatory phase for the next lactation and that dry cows are considered an investment for the next lactation. Prepartum transition dairy cows should be managed and fed so that at parturition and initiation of lactation, the cow is physiologically prepared to make the necessary adjustments to calcium and energy demands. The hypocalcemia must commonly occurs during this period and may lead to decrease dry matter intake (DMI) after calving, increased risk of secondary diseases, decreased milk production, and decreased fertility. Therefore, this work has the objective to analyze puerperal hypocalcemia control strategies, stressing nutritional and manage aspects, based on literature in the subject

Utilização de dietas aniônicas como prevenção de hipocalcemia em vacas de leite

Durante o período pós-parto, as vacas de leite têm um elevado risco de desenvolver doenças metabólicas que prejudicam a produção de leite e desempenho reprodutivo subsequente. Muitas dessas doenças são resultados do manejo nutricional inadequado durante o período seco. Pelo fato das vacas secas não contribuem para a produção de leite, muitos produtores ignoram esses animais, e as suas necessidades nutricionais são comprometidos. Veterinários devem convencer os produtores de leite que o período seco é uma fase preparatória para a próxima lactação e que vacas secas são um investimento para a próxima lactação. Vacas de leite do período de transição do pré-parto devem ser manejadas e alimentadas para que no dia do parto e início da lactação as vacas estejam fisiologicamente preparadas para fazer os ajustes necessários nas demandas de cálcio e energia. A hipocalcemia ocorre mais comumente neste período e pode levar a uma redução no consumo de matéria seca (CMS) depois do parto, maior risco de doenças secundárias, diminuição da produção de leite e redução da fertilidade. Portanto, este trabalho tem o objetivo de analisar as estratégias de controle da hipocalcemia puerperal, enfatizando aspectos do manejo nutricional, com base na literatura sobre o assunto.During the postpartum period, dairy cows are at a high risk to develop metabolic diseases that impair milk production and subsequent reproductive performance. Many of these diseases are the result of improper nutritional management during the dry period. Because dry cows not contribute to the milk check, many producers ignore these animals, and their nutritional needs are compromised. Veterinarians must convince dairy producers that the dry period is a preparatory phase for the next lactation and that dry cows are considered an investment for the next lactation. Prepartum transition dairy cows should be managed and fed so that at parturition and initiation of lactation, the cow is physiologically prepared to make the necessary adjustments to calcium and energy demands. The hypocalcemia must commonly occurs during this period and may lead to decrease dry matter intake (DMI) after calving, increased risk of secondary diseases, decreased milk production, and decreased fertility. Therefore, this work has the objective to analyze puerperal hypocalcemia control strategies, stressing nutritional and manage aspects, based on literature in the subject

Second asymptomatic carotid surgery trial (ACST-2) : a randomised comparison of carotid artery stenting versus carotid endarterectomy

Background: Among asymptomatic patients with severe carotid artery stenosis but no recent stroke or transient cerebral ischaemia, either carotid artery stenting (CAS) or carotid endarterectomy (CEA) can restore patency and reduce long-term stroke risks. However, from recent national registry data, each option causes about 1% procedural risk of disabling stroke or death. Comparison of their long-term protective effects requires large-scale randomised evidence. Methods: ACST-2 is an international multicentre randomised trial of CAS versus CEA among asymptomatic patients with severe stenosis thought to require intervention, interpreted with all other relevant trials. Patients were eligible if they had severe unilateral or bilateral carotid artery stenosis and both doctor and patient agreed that a carotid procedure should be undertaken, but they were substantially uncertain which one to choose. Patients were randomly allocated to CAS or CEA and followed up at 1 month and then annually, for a mean 5 years. Procedural events were those within 30 days of the intervention. Intention-to-treat analyses are provided. Analyses including procedural hazards use tabular methods. Analyses and meta-analyses of non-procedural strokes use Kaplan-Meier and log-rank methods. The trial is registered with the ISRCTN registry, ISRCTN21144362. Findings: Between Jan 15, 2008, and Dec 31, 2020, 3625 patients in 130 centres were randomly allocated, 1811 to CAS and 1814 to CEA, with good compliance, good medical therapy and a mean 5 years of follow-up. Overall, 1% had disabling stroke or death procedurally (15 allocated to CAS and 18 to CEA) and 2% had non-disabling procedural stroke (48 allocated to CAS and 29 to CEA). Kaplan-Meier estimates of 5-year non-procedural stroke were 2·5% in each group for fatal or disabling stroke, and 5·3% with CAS versus 4·5% with CEA for any stroke (rate ratio [RR] 1·16, 95% CI 0·86-1·57; p=0·33). Combining RRs for any non-procedural stroke in all CAS versus CEA trials, the RR was similar in symptomatic and asymptomatic patients (overall RR 1·11, 95% CI 0·91-1·32; p=0·21). Interpretation: Serious complications are similarly uncommon after competent CAS and CEA, and the long-term effects of these two carotid artery procedures on fatal or disabling stroke are comparable