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1.
Rev Sci Tech ; 39(2): 481-490, 2020 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33046927

RESUMO

Climate change is predicted to change the nature and distribution of global farming systems, and strategies will be needed to adapt and optimise global food-producing systems. If genomic technologies are to be useful in this scenario, there is a need for the careful definition of phenotypes and routine sample collection, as well as large-scale genotyping of animal populations. Genomic tools will greatly enhance the characterisation of available germplasm and exploration of local genetic resources, while faster and cheaper DNA sequencing is leading to an increased understanding of the underlying genetic basis of traits. The use of genomic tools to increase animal resilience, reduce methane emissions from cattle and sheep, improve disease resistance, decrease environmental impact, reduce competition for land and water and, finally, increase production may be the most feasible path for the future of livestock production. In this review, the authors discuss various genomic strategies in the light of climate change, focusing on the selection of resistant/tolerant animals, landscape genomics, metagenomics and gene editing.


Assuntos
Mudança Climática , Genômica , Agricultura , Animais , Bovinos , Genoma , Gado , Ovinos
2.
Rev Sci Tech ; 39(2): 417-425, 2020 Aug.
Artigo em Espanhol, Inglês | MEDLINE | ID: mdl-33046933

RESUMO

This case study outlines the actions of Cuba's Veterinary Service, as part of the country's disaster risk reduction and management system, in response to Hurricane Irma. The phenomenon affected ten of Cuba's 15 provinces and caused significant damage in 53 of its municipalities (29.6%). During the response effort, the pre-established measures for the various phases (warning, alert and emergency) were deployed according to the disaster reduction plans for each level. In all provinces, animals were protected by moving them to safer locations, allowing for pre-established sanitary measures and technical assistance. Nonetheless, damage was incurred, mainly to the roofs of some animal housing. The following deaths were recorded: 210,150 poultry, 2,752 cattle (of which 73.8% were calves) and 866 pigs (of which 68% were young animals). In addition, 7% of the inventory of hives was damaged and 3.3% of hives were lost. Damage to infrastructure included: 466 poultry houses, 1,422 cattle houses, 431 pig houses, 1,200 wind pumps and 13 of the country's 17 feed concentrate plants. As no major damage was reported to the Veterinary Service's facilities (laboratories and offices), its viability was guaranteed at all times. Rapid damage assessment enabled priorities for rehabilitation and recovery actions to be set, with the result that, just three months after the hurricane had struck, 67% of the poultry houses and 33% of the pig houses had been restored. This article focuses on preparedness, response and lessons learned.


Assuntos
Tempestades Ciclônicas , Planejamento em Desastres , Desastres , Animais , Bovinos , Cuba , Abrigo para Animais , Suínos
3.
J Environ Qual ; 49(1): 228-235, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33016360

RESUMO

Manure composting is a common management practice for cattle feedlots, but gaseous emissions from composting are poorly understood. The objective of this study was to quantify ammonia (NH3 ), nitrous oxide (N2 O), carbon dioxide (CO2 ), and methane (CH4 ) emissions from windrow composting (turning) and static stockpiling (nonturning) of manure at a commercial feedlot in Australia. An inverse-dispersion technique using an open-path Fourier transform infrared (OP-FTIR) spectrometer gas sensor was deployed to measure emissions of NH3 , N2 O, CO2 , and CH4 over a 165-d study period, and 29 and 15% of the total data intervals were actually used to calculate the fluxes for the windrow and stockpile, respectively. The nitrogen (N) lost as NH3 and N2 O emissions represented 26.4 and 3.8% of the initial N in windrow, and 5.3 and 0.8% of that in the stockpile, respectively. The carbon (C) lost as CO2 and CH4 emissions represented 44 and 0.3% of the initial C in windrow, and 54.8 and 0.7% of that in the stockpile, respectively. Total greenhouse gas (GHG) emissions from the manure windrow were 2.7 times higher than those of the stockpiled manure. This work highlights the value that could be accrued if one could reduce emissions of NH3 -N and N2 O-N from composting, which would retain manure N content while reducing GHG emissions.


Assuntos
Compostagem , Animais , Austrália , Bovinos , Gases , Efeito Estufa , Esterco
4.
J Environ Qual ; 49(3): 628-639, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-33016385

RESUMO

An integrated crop-livestock system (ICLS), when managed properly, can help in mitigating soil surface greenhouse gas (GHG) fluxes, especially carbon dioxide (CO2 ), methane (CH4 ), and nitrous oxide (N2 O). However, the impacts of an ICLS on GHG fluxes are poorly understood. The present study was conducted at two sites (northern Brookings [Brookings-N] and northwestern Brookings [Brookings-NW]) established in 2016 and 2017, respectively, under loamy soils in South Dakota. The specific objective was to evaluate the impact of cover crops (CCs) and grazed CCs under oat (Avena sativa L.)-CCs-maize (Zea mays L.) rotation on GHG fluxes. Study treatments included the following: (a) a legume-dominated CC (LdC), (b) a cattle-grazed LdC (LdC+G), (c) a grass-dominated CC (GdC), (d) a cattle-grazed GdC (GdC+G), and (e) one without CC or grazing (NC). Greenhouse gas monitoring occurred weekly during the growing crop seasons in 2016 and 2017 for Brookings-N and in 2017 and 2018 for Brookings-NW. Data showed that cumulative CO2 and N2 O fluxes at Brookings-N were lower for GdC+G (4042 kg C ha-1 for CO2 and 1499 g N ha-1 for N2 O) than for LdC+G (4819 kg C ha-1 for CO2 and 2017 g N ha-1 for N2 O), indicating the superiority of GdC+G over LdC+G in reducing GHG fluxes. However, no effect from grazed CC on cumulative CO2 and N2 O fluxes were observed at the Brookings-NW site. Cumulative CH4 flux was not affected by an ICLS at either site. This short-term investigation showed that, in general, CCs and grazing of CCs and maize residue did not impact GHG fluxes.


Assuntos
Gases de Efeito Estufa , Animais , Bovinos , Produtos Agrícolas , Óxido Nitroso/análise , Solo , Zea mays
5.
J Environ Qual ; 49(2): 324-334, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33016426

RESUMO

Managing a sustainable dairy farm requires balancing phosphorus (P) imports and exports that enter and leave through the farm gate. Over the long term, P surpluses will elevate soil-test P concentrations above crop requirements through routine land applications of manure. The objectives of this study were aimed at Virginia dairy farms (a) to determine P mass balances, (b) to define potential guidelines for a sustainable and feasible zone of operation based on P balance and P use efficiency, and (c) to assess risk factors driving P surplus and P use inefficiencies. Data on farm-gate P imports and exports via feed, manure, crops, fertilizers, bedding, animals, and milk were collected for 58 dairy farms in Virginia. There was no relationship between farm P balance and milk production, indicating that a P surplus was not necessary for good milk productivity. A feasible P balance limit was calculated below which 75% of farms could operate, and this was 18.7 kg P ha-1 . Two risk factors were identified for farms having a P balance above this limit: (a) land application of poultry litter and (b) excessive import of P through feed. Combined dairy and beef operations generally had more land and a lower P balance, whereas having combined dairy and poultry did not raise the P balance as long as poultry litter was exported. Dairy farms in Virginia can operate with a sustainable P balance as long as they avoid using excessive poultry litter and pay attention to P imported through purchased feed.


Assuntos
Indústria de Laticínios , Fósforo/análise , Ração Animal/análise , Animais , Bovinos , Fazendas , Nitrogênio/análise , Virginia
6.
J Environ Qual ; 49(5): 1435-1444, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33016451

RESUMO

Chlortetracycline (CTC), an antimicrobial administered as a feed additive to cattle, swine, and poultry, is present in the corresponding manure. Land application of raw or processed (composted or stockpiled) manure provides a mechanism by which CTC (and other antimicrobials) enters the environment and becomes available for transport to surface receiving waters via rainfall or snowmelt runoff. Chlortetracycline has been detected in Canadian surface waters, but little has been reported on its fate in aquatic ecosystems. To address this knowledge gap, the dissipation of CTC-enol was monitored in deionized water and water typical of wetlands within the prairie region of Canada. In deionized water, CTC-enol tautomerized to CTC-keto, and both tautomers epimerized to 4-epi-CTC-enol and 4-epi-CTC-keto, respectively. Irreversible isomerization to iso-CTC occurred, which then epimerized to 4-epi-iso-CTC. In wetland water, although tauterization of CTC-enol to CTC-keto occurred, there was no evidence of the formation of the 4-epimers of either CTC-enol or CTC-keto. The major product formed in the wetland water was iso-CTC, some of which epimerized to 4-epi-iso-CTC. Although CTC-enol was shown to tautomerize to CTC-keto, the concentration of CTC-keto remained low in both deionized and wetland water, suggesting that the isomerization of CTC-enol to iso-CTC most likely occurred via CTC-keto. The dissipation of CTC-enol in wetland water was described by pseudo first-order kinetics with a DT50 (time required for 50% dissipation) value of 4.8 h. The short DT50 value of CTC and reduced antimicrobial activity of iso-CTC and 4-epi-iso-CTC suggest a lower probability for selection for CTC-resistant bacteria in Canadian Prairie aquatic ecosystems.


Assuntos
Clortetraciclina , Animais , Canadá , Bovinos , Ecossistema , Pradaria , Isomerismo , Suínos , Áreas Alagadas
7.
J Environ Qual ; 49(4): 1000-1010, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33016497

RESUMO

Expansion of subsurface drainage into forage production may have a deleterious effect on surface waters due to increased nitrogen and phosphorus loading. The impact of controlled subsurface drainage (CD) on nitrogen and phosphorus loss compared with free subsurface drainage (FD) in tile drainage water has been explored to a lesser extent from forage production systems. This study quantifies the effects of CD and FD on average seasonal concentrations and cumulative loads of the total suspended solids (TSS), nitrate nitrogen (NO3 -N), and dissolved reactive phosphorus (DRP) in subsurface drainage water from a poorly drained floodplain soil in a cereal rye (Secale cereale L.)-sorghum [Sorghum bicolor (L.) Moench] rotation with rotational cattle grazing. During all crop seasons of sorghum production (2010-2013), CD had 6.03-9.63 mg L-1 less NO3 -N than FD. Mean DRP concentration was significantly higher for CD than for FD during all seasons except for sorghum in 2012-2013. Average cumulative discharge was 38 and 314 m3 ha-1 less for CD than for FD during sorghum and cereal rye growing seasons, respectively. Controlled drainage had 0.68-6.14 kg ha-1 lower cumulative NO3 -N loads than FD. The DRP loads were dependent on discharge. During sorghum growing seasons, TSS and DRP loads were 79-90% lower in CD compared with FD. The ability to reduce drainage water flow from tiles and subsequent nitrogen and phosphorus loading with CD compared with FD in a floodplain soil indicates that CD can be effective best management practice for forage production systems.


Assuntos
Agricultura , Solo , Animais , Bovinos , Nitrogênio , Nutrientes , Fósforo
8.
Asian Cardiovasc Thorac Ann ; 28(7): 381-383, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33023307
9.
Zootaxa ; 4821(3): zootaxa.4821.3.3, 2020 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-33056311

RESUMO

A new species, Cornigamasus allotritosternus sp. nov., is described based on the larva, protonymph, deutonymph and adult female and male collected from cow dung in Guizhou Province, China. The ontogenetic development of the gnathotectum, dorsal shields, ventral shields, and the chaetotaxy of the gnathosoma, idiosoma and legs are discussed and illustrated.


Assuntos
Ácaros , Animais , Bovinos , China , Feminino , Larva , Masculino , Sensilas
10.
Vet Rec ; 187(8): 323, 2020 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-33060234
11.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2589-2593, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018536

RESUMO

Left ventricular assist devices (LVADs) are used to treat patients with severe (New York Heart Association class IV) heart failure. Thrombosis and bleeding are severe LVAD-related complications; thus, an effective anticoagulation regimen is crucial for successful postoperative management. The CH-VAD™ (CH Biomedical, Inc.) is a small, implantable, full-support (>5 L/min) LVAD with a centrifugal flow pump that has a fully magnetically levitated rotor, which confers superior hemocompatibility. In this study, the CH-VAD™ was implanted in two calves to evaluate its hemocompatibility and to establish an anticoagulation regimen for future GLP (good laboratory practice) studies. Heparin infusion was used during the surgery, and during postoperative management, the proper dosage of warfarin was given orally to maintain an international normalized ratio (INR) between 2.0 and 3.0. Pump performance, animal condition, and hematology results were recorded throughout the study (approximately 60 days). The results show that under the established anticoagulation regimen, the CH-VAD™ was well tolerated in the bovine model, with no significant thrombus or thromboembolic lesion formation in distal end organs. Low plasma free hemoglobin levels suggest that the device did not cause hemolysis. These results and the experience gained pave the way for future GLP studies.


Assuntos
Insuficiência Cardíaca , Coração Auxiliar , Trombose , Animais , Bovinos , Hemodinâmica , Humanos , Varfarina
12.
Annu Int Conf IEEE Eng Med Biol Soc ; 2020: 2707-2710, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-33018565

RESUMO

Pulse wave velocity (PWV) is a function of the artery's material property, and its incremental nature in elastic modulus led to the concept of incremental PWV. Recent advancements in technology paved the way for reliable measurement of the variation in PWV within a cardiac cycle. This change in PWV has shown its potential as a biomarker for advanced cardiovascular diagnostics, screening, and has recently started using as a vascular screening tool and medical device development. In this work, we have demonstrated the concept of inter and intra-cycle variations of PWV with pressure using an excised bovine carotid artery. Results demonstrated that local PWV measured at the foot of the waveform followed the same trend as of the pressure. As the pressure level was increased to 68% across the cycles, resulting PWV increased up to 81%. An exponential PWV-Pressure relationship was obtained, in agreement with the widely used models. The incremental nature of PWV was recorded in a reflection-free region of the pressure pulse wave. This was further demonstrated in continuous pulse cycles with varying pressure ranges, by comparing the PWV values at two fiduciary points selected in the upstroke of the pressure wave. On average, a 48.11% increase in PWV was observed for 31.04% increase in pressure between the selected fiducial points within a pulse cycle. The article concludes, highlighting the clinical significance of incremental PWV.Clinical Relevance- This experimental study supplements the evidence for the incremental nature of PWV within a cardiac cycle, which has the potential for being a biomarker for advanced cardiovascular screening and diagnostics.


Assuntos
Artérias Carótidas , Análise de Onda de Pulso , Animais , Pressão Sanguínea , Artéria Carótida Primitiva , Bovinos , Frequência Cardíaca
13.
Int J Esthet Dent ; 15(4): 490-502, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33089262

RESUMO

AIM: This study assessed the changes in color and translucency of dentin and enamel after staining and bleaching procedures as well as the contribution of the tissues to color change (CTCC). MATERIALS AND METHODS: Fifty enamel-dentin specimens were obtained from bovine incisors and grouped into 10 blocks based on the similarity of the baseline color. One specimen in each block was used as the control, and the others were intrinsically (blood) or extrinsically (coffee) stained. One stained specimen for each pigment was bleached with 35% hydrogen peroxide. The enamel was separated from the dentin, and the tooth color and translucency parameter (TP) were measured individually and after recombining these substrates. Changes in color (ΔE00), whitening index (WI), and TP caused by the staining and bleaching procedures were estimated through assessing the color differences compared with the controls. CTCC was also calculated by recombining the enamel and dentin tissues from different treatments. The data were analyzed using the paired t test or the two-way repeated measures ANOVA (α = 0.05). RESULTS: Extrinsic staining procedures produced higher color changes than intrinsic ones, except in dentin. The highest bleaching effect was observed in the dentin of specimens that were extrinsically stained. Similar CTCC values were observed for the dentin and enamel for both the staining and bleaching procedures. Except for the specimens that were treated with intrinsic staining and became more translucent after the bleaching procedure, the other treatments resulted in non-significant TP changes. CONCLUSIONS: Staining the specimens extrinsically resulted in higher color change than staining them intrinsically, and these specimens were more affected by the bleaching procedure. Enamel and dentin demonstrated similar CTCC values.


Assuntos
Clareamento Dental , Animais , Bovinos , Esmalte Dentário , Dentina , Peróxido de Hidrogênio , Coloração e Rotulagem , Clareamento Dental/efeitos adversos
14.
Zootaxa ; 4859(3): zootaxa.4859.3.6, 2020 Oct 07.
Artigo em Inglês | MEDLINE | ID: mdl-33056191

RESUMO

Species concentration and composition of endosymbiotic ciliates were investigated in the forestomach contents of 12 dromedary camels (Camelus dromedarius) and the ruminal contents of 16 domestic cattle (Bos taurus taurus) living in Ben Gardane, Tunisia. Sixteen species and 8 morphotypes, belonging to 8 genera, were identified from dromedary camels, and 18 species and 13 morphotypes, belonging to 8 genera, were identified from domestic cattle. This is the first report on the endosymbiotic ciliated protozoan biota of dromedary camels and cattle living in Tunisia. The mean density (± SD) of ciliates in the forestomach samples of dromedary camels and the ruminal samples of domestic cattle was 65.4 ± 69.4 × 104 cells mL-1 and 54.2 ± 55.8 × 104 cells mL-1, respectively. Diplodinium cameli and Blepharoconus krugerensis were detected for the first and second time, respectively, from the ruminal contents of cattle. Caloscolex camelinus and B. krugerensis were studied in detail with a scanning electron microscope.


Assuntos
Camelus , Cilióforos , Animais , Biota , Bovinos , Rúmen , Tunísia
15.
Am J Dent ; 33(5): 227-234, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33017523

RESUMO

PURPOSE: To evaluate the influence of different post-endodontic techniques on the fatigue survival and biomechanical behavior of crowned restored central incisors. METHODS: The crowns of 69 bovine incisors were cut, and the roots were treated endodontically and assigned randomly into three groups (n=23): resin composite buildup (BUP), glass fiber post-retained resin composite buildup (GFP), and cast post-and-core (CPC). They received full crown preparation with 2 mm ferrule, and a leucite-reinforced ceramic crown was cemented adhesively. Three specimens from each group were tested monotonically. The remaining specimens were subjected to the stepwise stress fatigue test until fracture or suspension after 1.5 x 106 cycles in a chewing simulator. The load and step at which each specimen failed were analyzed by Kaplan-Meier and Mantel-Cox (log-rank test) statistics, followed by multiple pairwise comparisons, at 5% significance level. The three groups tested (BUP, GFP, and CPC) were 3D modeled (Rhinoceros 4.0) and the maximum principal stress (MPa) criteria were used to calculate the results using FEA. RESULTS: There was no statistical difference between the treatments regarding the load or the number of cycles (Mantel-Cox log-rank test for trend, X²= 0.015, df=1, P= 0.901, X²=3.171, df=1, P= 0.995). Crown cracks were the predominant failure mode, and oblique root fractures were only observed in groups GFP and CPC. In endodontically treated incisors with a 2-mm ferrule, the post-endodontic treatment had no significant effect on fatigue survival. Non-restorable fractures only occurred in teeth restored with posts. CLINICAL SIGNIFICANCE: Although the clinical significance of laboratory studies has some limitations, this study suggests that composite buildups without posts may be an option for restoring endodontically treated incisors with 2 mm ferrule height.


Assuntos
Incisivo , Técnica para Retentor Intrarradicular , Animais , Bovinos , Resinas Compostas , Coroas , Análise do Estresse Dentário
16.
Vet Clin North Am Food Anim Pract ; 36(3): 509-524, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33032696

RESUMO

This article addresses diagnostic challenges involving toxicology cases that are multifactorial in nature, often involving sublethal exposures to multiple toxicants and/or other etiologies that are not toxic. Gold standard diagnostic approaches were developed under the assumption that cases were undoubtedly intoxications, and they still are applicable to those cases. A more integrated diagnostic approach, focusing on the initial problem list, is consistent with how veterinarians diagnose most cases. Livestock ownership attitudes continue to evolve. Ongoing threats to the financial well-being of animal agriculture ultimately will have an impact on the ability of producers to maintain health and performance of livestock.


Assuntos
Doenças dos Animais/induzido quimicamente , Xenobióticos/envenenamento , Animais , Bovinos , Gado , Ruminantes , Medicina Veterinária/métodos , Medicina Veterinária/normas
17.
Vet Clin North Am Food Anim Pract ; 36(3): 715-723, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33032701

RESUMO

The liver is one of the most commonly affected organs by ingested toxicants. This article familiarizes veterinarians with clinical signs, serum biochemistry changes, necropsy findings, and field information found in livestock poisonings with hepatotoxic plants. The focus is on the most common plant-derived hepatotoxins important to livestock in North America. Pyrrolizidine alkaloids are covered in greater detail than the other toxins, because they are likely the most important plant-derived toxins worldwide in livestock, wildlife, and even human exposure. Additionally, many of the principles discussed regarding clinical diagnosis of pyrrolizidine alkaloid intoxication can be applied to the other poisonous plants listed.


Assuntos
Doenças dos Bovinos/etiologia , Hepatopatias/veterinária , Intoxicação por Plantas/veterinária , Plantas Tóxicas/envenenamento , Animais , Bovinos , Hepatopatias/etiologia , Gado , América do Norte , Intoxicação por Plantas/etiologia , Alcaloides de Pirrolizidina/envenenamento
18.
J Environ Radioact ; 222: 106307, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32892894

RESUMO

In Japan, the radiocesium activity concentration in milk must be less than 50 Bq/kg-fresh to meet shipping standards, and the radiocesium concentration of the diet fed to dairy cattle must be less than 500 Bq/kg-dry. After the Fukushima nuclear accident in 2011, we conducted two experiments to investigate whether Prussian blue (PB) could suppress the radiocesium (134Cs + 137Cs) activity concentration in Japanese cattle' milk. In experiment 1, four cattle were fed a diet with a radiocesium activity concentration of 175 Bq/kg-dry, with or without PB supplementation. The PB intake ranged from 0 to 3.0 g/day, and the average radiocesium intake was 3.42 kBq/day in all treatments. The radiocesium activity concentration in milk decreased from 16.4 to 8.6 Bq/kg-fresh, and the transfer coefficient of radiocesium from diet to milk (Fm) decreased from 4.77 × 10-3 to 2.61 × 10-3 with increased PB intake. In experiment 2, three cattle were fed another diet including a radiocesium activity concentration of 927 Bq/kg-dry of with or without PB supplementation. The PB intake ranged from 0 to 18.9 g/day, and the average radiocesium intake was 15.2 kBq/day in all treatments. The milk's radiocesium activity concentration decreased from 24.3 to 4.2 Bq/kg-fresh, and the Fm decreased from 1.68 × 10-3 to 0.28 × 10-3 with increased PB intake. Our results suggest that both the radiocesium activity concentration in milk and Fm can be reduced by PB, and that Fm is affected by diet. We recommend cattle should be fed absorbents such as PB to minimize the risk of milk radiocesium activity concentration exceeding 50 Bq/kg-fresh even if the diet has a radiocesium activity concentration of less than 500 Bq/kg-dry.


Assuntos
Radioisótopos de Césio , Acidente Nuclear de Fukushima , Leite , Monitoramento de Radiação , Animais , Bovinos , Radioisótopos de Césio/análise , Dieta , Ferrocianetos , Japão , Leite/química
19.
Benef Microbes ; 11(5): 477-488, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32877228

RESUMO

Neonatal calf diarrhoea is one of the challenges faced by intensive farming, and probiotics are considered a promising approach to improve calves' health. The objective of this study was to evaluate the effect of potential probiotic lactobacilli on new-born dairy calves' growth, diarrhoea incidence, faecal score, cytokine expression in blood cells, immunoglobulin A (IgA) levels in plasma and faeces, and pathogen abundance in faeces. Two in vivo assays were conducted at the same farm in two annual calving seasons. Treated calves received one daily dose of the selected lactobacilli (Lactobacillus reuteri TP1.3B or Lactobacillus johnsonii TP1.6) for 10 consecutive days. A faecal score was recorded daily, average daily gain (ADG) was calculated, and blood and faeces samples were collected. Pathogen abundance was analysed by absolute qPCR in faeces using primers directed at Salmonella enterica, rotavirus, coronavirus, Cryptosporidium parvum and three Escherichia coli virulence genes (eae, clpG and Stx1). The faecal score was positively affected by the administration of both lactobacilli strains, and diarrhoea incidence was significantly lower in treated calves. No differences were found regarding ADG, cytokine expression, IgA levels and pathogen abundance. Our findings showed that oral administration of these strains could improve gastrointestinal health, but results could vary depending on the calving season, which may be related to pathogen seasonality and other environmental effects.


Assuntos
Doenças dos Bovinos/terapia , Diarreia , Lactobacillus johnsonii/metabolismo , Lactobacillus reuteri/metabolismo , Probióticos/uso terapêutico , Animais , Animais Recém-Nascidos , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/prevenção & controle , Infecções por Coronavirus/prevenção & controle , Infecções por Coronavirus/veterinária , Criptosporidiose/prevenção & controle , Citocinas/sangue , Indústria de Laticínios , Diarreia/prevenção & controle , Diarreia/terapia , Diarreia/veterinária , Infecções por Escherichia coli/prevenção & controle , Infecções por Escherichia coli/veterinária , Fezes/virologia , Trato Gastrointestinal/microbiologia , Imunoglobulina A/sangue , Infecções por Rotavirus/prevenção & controle , Infecções por Rotavirus/veterinária , Salmonelose Animal/prevenção & controle
20.
Vet Parasitol Reg Stud Reports ; 21: 100435, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32862896

RESUMO

Faecal specimens from 36 scouring neonatal calves from two dairy farms located in the Al Ain region of the UAE were screened with pathogen-specific antigen ELISA for Cryptosporidium parvum, Escherichia coli K99, rotavirus, and coronavirus. Additionally, faecal smears were stained with modified-acid-fast for Cryptosporidium oocysts, and the VITEK 2 system plus Gram's stain used to identify bacteria isolated from the faecal samples. Farm management practices were also evaluated during a farm visit. Of the 36 calves, 29, 13, 5, and 6 were positive for C. parvum, E. coli K99, bovine coronavirus, and rotavirus antigens respectively, while 27 were positive for Cryptosporidium oocysts. In various combinations, mixed infections were detected in 20/36 calves. This is the first report of C. parvum, E. coli K99, Salmonella spp., rotavirus, and coronavirus in ≤14-days-old scouring neonatal dairy calves from the UAE. Molecular characterization of these pathogens and nationwide epidemiological calf scour studies are recommended.


Assuntos
Doenças dos Bovinos/epidemiologia , Criptosporidiose/epidemiologia , Cryptosporidium parvum , Animais , Animais Recém-Nascidos/microbiologia , Animais Recém-Nascidos/parasitologia , Bovinos , Doenças dos Bovinos/microbiologia , Doenças dos Bovinos/parasitologia , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/veterinária , Coronavirus Bovino , Indústria de Laticínios , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Infecções por Escherichia coli/veterinária , Feminino , Masculino , Infecções por Rotavirus/epidemiologia , Infecções por Rotavirus/veterinária , Salmonelose Animal/epidemiologia , Emirados Árabes Unidos/epidemiologia
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