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Prevalence Study, Pathological, Hematological, and Electrocardiographic Indices of Abomasal Ulcers at Sanandaj Abattoir
2021
Abaszadeh, Mohammad Sina | Fakour, Shahin | Akradi, Loghman
BACKGROUND: Abomasal ulcer is a disease of digestive system in ruminants. The clinical signs vary widely depending on the type of abomasal ulcer. The economic losses of this disease include decreased milk yield and mortality. OBJECTIVES: The present study aimed to determine the frequency, type of ulcer, pathological, hematological, and electrocardiographic indices in the slaughtered cattle in Sanandaj abattoir. METHODS: A total of 400 cattle were randomly selected with both sexes and 1-2, 2-3, 3-4, and ≥4 years of age. They were grouped during three seasons and the abomasal ulcer was evaluated. Blood sample was collected and electrocardiogram was recorded before they were slaughtered. Abomasal lesions were assessed macroscopically and histopathologically in the slaughtered cattle. RESULTS: Out of the 400 abomasom examined, 51 (12.75 %) were affected by abomasal ulcers, all of which were type-1 ulcer. Subtypes 1a, 1b, 1c, and 1d. 35 cattle (68.7 %) had the types of arrhythmia. The most frequent of them was sinus arrhythmia and sinus tachycardia. Neutrophilia and reduction in MCHC were significantly more than the other hematological indices (p < /em>˂0.05). There was a significant relationship between the prevalence of abomasal ulcers and arrhythmia, gender, age, and season (p < /em>˂0.05). Furthermore, there was a significant relationship between electrocardiographic and hematological indices in the affected cattle (p < /em>˂0.05). CONCLUSIONS: The results of this study revealed a high prevalence of abomasal ulcer in the studied area. They also indicated that the electrocardiographic and hematological changes could be helpful in the diagnosis of abomasal ulcer.
Afficher plus [+] Moins [-]Spontaneous alteration of blood pH by a bicarbonate buffer system during experimental hypercalcaemia in cows
2021
Ro Younghye | Choi Woojae | Hong Leegon | Kim Eunkyung | Choe Eunhui | Kim Danil
Maintaining mineral homeostasis as well as the secretion and metabolism of mineralotropic hormones is important for healthy of periparturient dairy cows. To increase the activity of mineralotropic hormones, blood pH can be adjusted. The purpose of this study was to investigate changes in blood pH and the mechanism of action of this change in induced hypercalcaemic cows.
Afficher plus [+] Moins [-]Comparative expression analysis of inflammatory and immune-related genes in cattle during acute infection with foot-and-mouth disease virus in Egypt
2021
El Nahas Abeer F. | Abd El Naby Walaa S.H. | Khatab Shymaa A. | Fergany Al-Zahraa A. | Rashed Rashed R.
Foot-and-mouth disease is a highly infectious viral disease affecting all cloven-footed domestic animals. The three foot-and-mouth disease virus (FMDV) serotypes A, O and SAT2 are at present the greatest threat to susceptible animals in Egypt. The aim of the present study was, for the host factors associated with different FMDV infections in cattle during the acute phase, to compare these factors’ influence on the expression of the IL-10, TLR-2, TNF-α, CXCL10, CD48, NFATC4 and IFNG inflammatory and immune-related genes.
Afficher plus [+] Moins [-]The spread and antimicrobial resistance of Staphylococcus aureus in South African dairy herds – A review
2021
Joanne Karzis | Inge-Marie Petzer | Vinny Naidoo | Edward F. Donkin
Staphylococcus aureus is internationally recognised as a principal agent of mastitis and the foremost reason for economic loss in the dairy industry. The limited data available on organism-specific antibiotic resistance surveillance in dairy cattle have stimulated the need for such a review article. The objective of this study was to review relevant literature on antimicrobial resistance of mastitis-causing staphylococci isolated from dairy cows in South Africa compared to other countries. Factors relating to the incidence of mastitis and treatment strategies in terms of the One Health concept and food security were included. The Web of Science (all databases) and relevant websites were used, and articles not written in English were excluded. The incidence of mastitis varied between South Africa and other countries. Antimicrobial resistance patterns caused by S. aureus also varied in regions within Southern Africa and those of other countries although some similarities were shown. Antimicrobial resistance differed between S. aureus bacteria that were maltose positive and negative (an emerging pathogen). The results highlighted the importance of the availability of organism-specific surveillance data of the incidence of mastitis and antibiotic resistance for specific countries and within similar climatic conditions. Accurate knowledge about whether a specific pathogen is resistant to an antibiotic within a certain climate, country, area or farm should reduce the incidence of unnecessary or incorrect treatment with antibiotics. This should enable dairy farmers to deal with these organisms in a more effective manner. Therefore such research should be ongoing.
Afficher plus [+] Moins [-]Replacing Subjective Assessment of Dairy Cows with Objective Measures
2021
Caleb Sagwa Barasa
In 2067 dairy farms in developing countries will be modernized and automated systems will replace much of the manual labour on farms. Traditionally, livestock management decisions have been based on almost entirely on observations, judgement, and experience of the farmer. However, such manual systems are inherently subjective, labour intensive, time consuming, invasive and unreliable. Today technology-oriented approaches are widely in use in animal agriculture. New data obtained using fast, real time, and affordable objective measures are becoming more readily available to aid farm level monitoring, awareness, and decision making. Computer vision technology and image analysis, digital twins, artificial intelligence, sensors, big data, and machine learning are a game changer in the livestock industry. This review aims at highlighting the main areas where digital technologies for improved animal monitoring and welfare are most applicable in dairy animals. In particular, body condition scoring, lameness detection, mastitis diagnosis, oestrus detection and pregnancy diagnosis. The environmental sustainability of digital technologies is also discussed. The application of technology offers new possibilities to realize food safety and quality, efficient and sustainable animal farming, healthy animals, guaranteed wellbeing and acceptable environmental impact of livestock production.
Afficher plus [+] Moins [-]Semi-stable production of bovine IL-4 and GM-CSF in the mammalian episomal expression system
2021
Blanco, Federico Carlos | Vazquez, Cristina Lourdes | García, Julia Sabio y | Rocha, Rosana Valeria | Gravisaco, María José | Forrellad, Marina Andrea | Magistrelli, Giovanni | Bigi, Fabiana
Granulocyte-macrophage colony stimulating factor (GM-CSF) and interleukin-4 (IL-4) are cytokines widely used in ex vivo monocyte differentiation experiments, vaccine formulations and disease treatment. The aim of this study was to produce recombinant bovine GM-CSF and IL-4 in an episomal expression system that conserves the postransductional modification of the native proteins and to use the products to differentiate bovine monocytes into dendritic cells. The recombinant proteins rGM-CSF and rIL-4 were expressed in PEAKrapid CRL-2828 human kidney cells, ATCC CRL-2828. The functional activity of the recombinant cytokines was monitored by registering morphological changes in bovine monocytes and assessing the expression of CD14 upon incubation with them. Both recombinant proteins were detected in the cell culture supernatant of transfected cells. Culture supernatants of transfected cells induced in bovine monocytes morphological changes that resemble macrophages or dendritic cells. In addition, bovine cells treated with rGM-CSF and rIL-4 showed reduced expression of the macrophage surface marker CD14 compared with untreated cells. This effect indicates the expected differentiation. The expression of the cytokines was stable after many successive cell passages and a freeze/thaw cycle. The semi-stable mammalian episomal expression system used in this study allowed us to easily produce functional bovine rGM-CSF and rIL-4 without the need for protein purification steps.
Afficher plus [+] Moins [-]Spontaneous alteration of blood pH by a bicarbonate buffer system during experimental hypercalcaemia in cows
2021
Ro, Younghye | Choi, Woojae | Hong, Leegon | Kim, Eunkyung | Choe, Eunhui | Kim, Danil
Maintaining mineral homeostasis as well as the secretion and metabolism of mineralotropic hormones is important for healthy of periparturient dairy cows. To increase the activity of mineralotropic hormones, blood pH can be adjusted. The purpose of this study was to investigate changes in blood pH and the mechanism of action of this change in induced hypercalcaemic cows. Six non-lactating Holstein cows were used in a 2 × 2 crossover design. To induce hypercalcaemia, calcium borogluconate was administered subcutaneously to experimental cows and normal saline was administered subcutaneously to control cows. Blood and urine samples were collected serially after administration. Whole blood without any anticoagulant was processed with a portable blood gas analyser. Plasma concentration and urinary excretion of calcium were measured. In hypercalcaemic cows, both blood and urine calcium levels were significantly increased at 8 h compared to those at 0 h (P < 0.05), and a spontaneous increase in blood pH was also observed. The calcium concentration in plasma was highest at 2 h after administration (3.02 ± 0.27 mmol/L). The change in pH correlated with that in bicarbonate (r = 0.781, P < 0.001) rather than that in partial pressure of CO₂ (r = 0.085, P = 0.424). Hypercalcaemia induced a spontaneous change in blood pH through the bicarbonate buffer system and this system may be a maintainer of calcium homeostasis.
Afficher plus [+] Moins [-]Acute and sub-chronic toxicity study of recombinant bovine interferon alpha in rodents
2021
Yu, Hai-Yang | Gao, Dong-Mei | Zhou, Wei | Xia, Bing-Bing | He, Zhi-Yuan | Wu, Bo | Jiang, Min-Zhi | Wang, Mingli | Zhao, Jun
Recombinant bovine interferon alpha (rBoIFN-α) has been demonstrated to have antiviral activity. However, no conduct of acute or chronic toxicity tests has been reported. Specific pathogen-free Sprague Dawley rats were administered doses at different concentrations through intraperitoneal or intravenous injection. After the administration (single for an acute toxicity test over 14 days or daily for a sub-chronic toxicity test over 30 days), the rats’ behaviour and other indicators and the degree of toxic reaction were continuously monitored. Blood was collected for haematological and serum biochemical examinations. At the end of the experiments, the rats were sacrificed for necropsy and histopathological tissue analysis. The external performance, behaviour characteristics, and changes in body temperature and body weight of the rats in each subgroup were comparable to the normal control subgroup. Except for a few cases, there were no lesions in the viscera’s pathological structures, and the blood parameters and biochemical indicators were not noticeably different from those of the control subgroup. This study suggests that rBoIFN-α seems to be safe for rats, and its use may foster the development of the cattle industry in China by protecting livestock health.
Afficher plus [+] Moins [-]Comparative expression analysis of inflammatory and immune-related genes in cattle during acute infection with foot-and-mouth disease virus in Egypt
2021
El Nahas, Abeer F. | Abd El Naby, Walaa S.H. | Khatab, Shymaa A. | Fergany, Al-Zahraa A. | Rashed, Rashed R.
Foot-and-mouth disease is a highly infectious viral disease affecting all cloven-footed domestic animals. The three foot-and-mouth disease virus (FMDV) serotypes A, O and SAT2 are at present the greatest threat to susceptible animals in Egypt. The aim of the present study was, for the host factors associated with different FMDV infections in cattle during the acute phase, to compare these factors’ influence on the expression of the IL-10, TLR-2, TNF-α, CXCL10, CD48, NFATC4 and IFNG inflammatory and immune-related genes. Vesicular fluid and epithelium samples were obtained from at least three infected cattle on the same affected farm during three different FMDV outbreaks and were used for serotyping of the virus and for expression analysis of host genes. A two-step RT-PCR was used for diagnosis of the virus with primers specific for each serotype. In quantitative PCR analysis, the expression patterns of TLR-2 and IFNG were prominent, while NFATC4 expression was absent in all FMDV-infected cattle. The highest expression of CD48 was associated with increased expression of other inflammatory and immune-related genes (IL-10, TLR-2, TNF-α and IFNG), which may be an indication of rapid virus clearance. The use of vesicular fluid and epithelium for investigation of viral and immune-related gene expression levels in acute FMDV infection is possible. Host-dependent variation in the expression of the studied genes was observed in different FMDV serotype outbreaks.
Afficher plus [+] Moins [-]Characterisation of a new molecule based on two E2 sequences from bovine viral diarrhoea-mucosal disease virus fused to the human immunoglobulin Fc fragment
2021
González Pose, Alaín | Montesino Seguí, Raquel | Maura Pérez, Rafael | Hugues Salazar, Florence | Cabezas Ávila, Ignacio | Altamirano Gómez, Claudia | Sánchez Ramos, Oliberto | Roberto Toledo, Jorge
Proper conformational arrangement of the E2 molecules of bovine viral diarrhoea-mucosal disease virus (BVD-MDV) is crucial to obtain an effective recombinant vaccine candidate against the disease. In this study, we characterised a new molecule composed of two distinct sequences of the E2 glycoprotein of BVD-MDV and the Fc fragment of human immunoglobulin (BVDE2Fc). The chimaeric protein was expressed in mammalian cell lines of different species by adenoviral transduction and purified by immobilised metal-affinity chromatography. The N-glycans were profiled by HPLC, and the BVDE2Fc immunogenicity was assessed in male mice. The antigen-antibody reactions were evaluated by ELISA. The MDBK cell line was selected from among five for the final production of BVDE2Fc. After purification to over 90%, the N-glycan profile showed neutral and complex oligosaccharides. The mouse immunisation induced a strong humoral response, which produced antibodies able to attach to conformational epitopes on E2 molecules, while the Fc fragment barely contributed to the immune response. Additionally, BVDE2Fc attached to antibodies from bovine sera positive to distinct BVD-MDV subtypes, whereas the loss of BVDE2Fc structure during the deglycosylation process considerably diminished those interactions. These results demonstrate that the structure of E2 molecules arranged in tandem and attached to an Fc fragment could represent a viable design for future vaccine candidates against BVD-MD.
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