Research in veterinary science最新文献

{"title":"Factors influencing the bioactivity of natural matrices: The case of osmolarity-dependent modulation of cell viability by different dilutions of camel urines","authors":"Carlos Iglesias Pastrana ,&nbsp;Maria Noemi Sgobba ,&nbsp;Francisco Javier Navas González ,&nbsp;Juan Vicente Delgado Bermejo ,&nbsp;Ciro Leonardo Pierri ,&nbsp;Giovanni Lentini ,&nbsp;Biagia Musio ,&nbsp;Taher Kamal Sayed Osman ,&nbsp;Vito Gallo ,&nbsp;Iola F. Duarte ,&nbsp;Lorenzo Guerra ,&nbsp;Elena Ciani","doi":"10.1016/j.rvsc.2024.105419","DOIUrl":"10.1016/j.rvsc.2024.105419","url":null,"abstract":"<div><div>The widespread practice of dromedary urinotherapy as a remedy for various illnesses, including cancer, is well-established in traditional dromedary countries. Researchers attempted to demonstrate anticancer properties of camel urine through <em>in vitro</em> experiments with debated outcomes. Notably, two critical aspects remained unexplored in those assays: (i) the osmolarity of tested urines, which can significantly influence <em>in vitro</em> results; (ii) the potential morphological changes of cells, following exposure to camel urines. In this study, we addressed these gaps by evaluating the osmolarity-dependent modulation of cell viability in human renal cell lines. In this regard, we assessed the impact of hyperosmolar mannitol-based solutions and dromedary urine on the viability and morphology of human non-tumor (HK2) and tumor renal cells (Caki-1). The results indicate that cell viability or morphology in both HK2 and Caki-1 cells are not significantly affected only if mannitol-induced hyperosmolarity is lower than 500 mOsm/L. Notably, when exposed to urine solution, diluted to &lt;500 mOsm/L, statistically significant antiproliferative effects were observed primarily in Caki-1 cells (in presence of two out of ten tested urine samples). Conversely, alterations in cell morphology were observed exclusively in HK2 cells when exposed to the same diluted camel urines. In order to investigate, at molecular level, the observed antiproliferative effects, a preliminary metabolomics analysis of the tested urine samples was performed to identify potential bioactive compounds. The Nuclear Magnetic Resonance (NMR) metabolic profiling revealed the presence of three antioxidant compounds, namely trigonelline, pyruvic acid and <em>N</em>-acetylglucosamine. In conclusion, our results highlight the importance of considering the critical role of osmolarity when evaluating the bioactive properties of camel urine <em>in vitro</em>, which should not be used to treat any illness as it is. Conversely, it can be considered the possibility to use camel urines as a source of bioactive compounds.</div></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"180 ","pages":"Article 105419"},"PeriodicalIF":2.2,"publicationDate":"2024-09-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142327450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Anatomical and functional basis of facial expressions and their relationship with emotions in horses","authors":"Barbara Zimmermann ,&nbsp;Alejandra Nelly Cristina Castro ,&nbsp;Pamela Anahí Lendez ,&nbsp;Mariano Carrica Illia ,&nbsp;María Paula Carrica Illia ,&nbsp;Alfredo Raúl Teyseyre ,&nbsp;Juan Manuel Toloza ,&nbsp;Marcelo Daniel Ghezzi ,&nbsp;Daniel Mota-Rojas","doi":"10.1016/j.rvsc.2024.105418","DOIUrl":"10.1016/j.rvsc.2024.105418","url":null,"abstract":"<div><p>An emotion is defined as the affective response to a stimulus that leads to specific bodily changes, enabling individuals to react to positive or negative environmental conditions. In the absence of speech, emotions in animals are primarily studied by observing expressive components, such as facial expressions. This review aims to analyze the available literature on the influence of environmental stimuli on measurable behaviors in horses, describing the anatomical components involved in perception at the central nervous system level and the efferent pathways that trigger facial muscle contraction or relaxation, thus altering facial expressions. Additionally, articles addressing the function of facial expressions in communication are discussed, emphasizing their role in social interactions in this species. While there is limited research on equine neurophysiology, considering the common structure of the limbic system in most mammals, studies conducted on canines and primates were taken into account. In conclusion, the article underscores the importance of understanding equine facial expressions to assess their emotional states and, by extension, their welfare.</p></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"180 ","pages":"Article 105418"},"PeriodicalIF":2.2,"publicationDate":"2024-09-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142270584","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of vaccination against Mycoplasma hyopneumoniae on divergent pig genetic groups","authors":"Katiene Regia Silva Sousa ,&nbsp;Waleska de Melo Ferreira Dantas ,&nbsp;Leandro Licursi de Oliveira ,&nbsp;Silvia Almeida Cardoso ,&nbsp;Renan dos Santos Araújo ,&nbsp;Simone Eliza Facioni Guimarães","doi":"10.1016/j.rvsc.2024.105417","DOIUrl":"10.1016/j.rvsc.2024.105417","url":null,"abstract":"<div><p>The bacterium <em>Mycoplasma hyopneumoniae</em> (Mhp) causes a chronic infectious respiratory disease in pigs, leading to important economic losses. This study aimed to compare the immune response of the local Piau breed and a commercial line to Mhp vaccination. For this, two phases were carried out. In the first, gene expression of toll-like receptors (TLR2, TLR4, TLR6, and TLR10) and cytokines (IL2, IL6, IL8, IL10, IL12, IL13, TNFα, and TGFβ) was assessed in porcine blood mononuclear cells (PBMC) from the two genetic groups before and after vaccination. In the second experiment, nitric oxide production, specific antibodies, and gene expression of toll-like receptors and cytokines were evaluated in bronchoalveolar lavage fluid (BALF) cells of vaccinated and unvaccinated pigs. After vaccination against Mhp, TLR2, TLR4, TLR6, TLR10, IL6, TNFα, and TGFβ expression levels were elevated in PBMC from commercial animals, and TLR6, TLR10, and TGFβ expression levels were elevated in PBMC from the Piau group. Vaccination also increased the production of Mhp-specific IgG antibodies in BALF cells in the Piau breed. Comparison of the two genetic groups revealed differences in TNFα and IL10 expression in BALF cells. These results show that Piau pigs have different immune responses to vaccination compared with commercial animals. It is worth noting that these genetic differences between both genetic groups may be related to phenotypic differences in Mhp resistance or susceptibility.</p></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"180 ","pages":"Article 105417"},"PeriodicalIF":2.2,"publicationDate":"2024-09-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142239402","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Metabolic and productive adaptive response of beef cows to successive short-nutritional challenges","authors":"K.G. Orquera-Arguero ,&nbsp;I. Casasús ,&nbsp;D. Villalba ,&nbsp;J. Ferrer ,&nbsp;M. Blanco","doi":"10.1016/j.rvsc.2024.105414","DOIUrl":"10.1016/j.rvsc.2024.105414","url":null,"abstract":"<div><p>This study aimed to analyze the response of lactating beef cows to repeated short nutritional challenges with their performance parameters and plasma metabolites. Multiparous lactating beef cows were subjected to three repeated nutritional challenges in the fourth month of lactation. Each challenge consisted of a 4-d feed restriction (55% of their average energy and protein requirements), followed by a 3-d refeeding period (100% requirements). Cows were classified into two groups differing in their performance (milk yield) and metabolic adaptation [non esterified fatty acids (<strong>NEFA</strong>) and β-hydroxybutyrate (<strong>BHB</strong>)] to diet changes (metabolic response, <strong>MR</strong>): High and Low MR cows, where the High MR cows showed a faster and larger response to diet changes than the Low MR cows (<em>P</em> &lt; 0.001). The loss in milk yield during restriction was the smallest in challenge 1 (<em>P</em> &lt; 0.001). Milk urea increased during restriction in challenges 1 and 2 (<em>P</em> &lt; 0.001). The High MR cows had greater <strong>NEFA</strong> concentrations than their Low MR counterparts during restrictions, and greater <strong>BHB</strong> concentrations during the restriction of challenge 2 (<em>P</em> &lt; 0.001). Restriction increased NEFA, BHB (only in the High MR cows) and urea (<em>P</em> &lt; 0.01). During refeeding, both milk yield and plasma metabolites recovered basal values (<em>P</em> &gt; 0.05). These results highlight the ability of beef cows to respond to and recover from successive short-term nutrient restrictions, and that despite a certain degree of sensitization of milk yield may have occurred, there were only minimal changes in the metabolic strategies triggered to cope with repeated underfeeding.</p></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"180 ","pages":"Article 105414"},"PeriodicalIF":2.2,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0034528824002819/pdfft?md5=32f0e2ea5ef48182a463b2d4ffa9bd53&pid=1-s2.0-S0034528824002819-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142173132","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cannabinoid receptor-2 expression in canine multicentric diffuse large B-cell lymphoma: An immunohistochemical, digital pathology and clinical analysis","authors":"Valentina Rinaldi ,&nbsp;Lorenzo Ressel ,&nbsp;Laura Bongiovanni ,&nbsp;Paolo Emidio Crisi ,&nbsp;Andrea Boari ,&nbsp;David Killick ,&nbsp;Roberto Chiocchetti ,&nbsp;Riccardo Finotello","doi":"10.1016/j.rvsc.2024.105411","DOIUrl":"10.1016/j.rvsc.2024.105411","url":null,"abstract":"<div><p>The cannabinoid 2 receptor (CB2R) is a crucial element of the endocannabinoid system (ECS), which is predominantly expressed on cells of the reticuloendothelial system. Alterations in CB2R expression have shown a prognostic role in various human neoplastic diseases and its expression has been studied in canine mast cell tumours (MCT). Canine diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma in dogs and has a variable clinical behaviour. Expression of CB2R was assessed by means of immunohistochemistry in fifteen dogs with proven histological diagnosis of DLBCL. A semiquantitative and quantitative assessment of immunoreactivity (IR) by digital analysis was performed in all cases. Our results indicate that CB2R expression is conserved in canine DLBCL but does not correlate with clinical outcome.</p></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"180 ","pages":"Article 105411"},"PeriodicalIF":2.2,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142239405","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Comparison of viraemia and nasal shedding after PRRSV-1 challenge following vaccination with three commercially available PRRS modified live virus vaccines","authors":"Laura Hancox ,&nbsp;Monica Balasch ,&nbsp;Jose Angulo ,&nbsp;Emer Scott-Baird ,&nbsp;Choew Kong Mah","doi":"10.1016/j.rvsc.2024.105416","DOIUrl":"10.1016/j.rvsc.2024.105416","url":null,"abstract":"<div><p>The effectiveness of three Porcine Reproductive and Respiratory Syndrome (PRRS) Modified Live Virus (MLV) vaccines against PRRSV viraemia and nasal shedding following experimental challenge was compared. The study comprised a negative control (T01), and three treatment groups (T02, T03 and T04) each vaccinated with a single dose of a commercial PRRS MLV vaccine, given in accordance with the vaccine's Summary of Product Characteristics (SPC). Pigs aged 21 days were vaccinated (day 0), challenged intranasally (day 28) with heterologous PRRSV-1-1 strain Olot/91, then monitored for PRRSV viraemia and nasal shedding for 12 days. After challenge, pigs were viraemic on fewer days in group T04 (0.67) than groups T01 (0.91), T02 (0.81) and T03 (0.97) (<em>P</em> &lt; 0.0296). From day 34, inclusive, serum PRRSV titres were lower in group T04 than negative controls (<em>P</em> ≤ 0.0001) and groups T02 and T03 (<em>P</em> ≤ 0.0047); serum PRRSV titre Area Under the Curve (AUC) for group T04 (42.34) was lower than in T01 (65.49), T02 (60.67) and T03 (67.38) (<em>P</em> &lt; 0.0100); pigs exhibited nasal shedding on fewer days in group T04 (0.40) than T01 (0.78), T02 (0.64) and T03 (0.56) (<em>P</em> &lt; 0.0101); and nasal shedding AUC for group T04 (8.52) was lower than in groups T01 (23.59, <em>P</em> &lt; 0.0001) and T02 (19.37, <em>P</em> = 0.0001). The ability of PRRS MLV vaccines to reduce the duration of viraemia and nasal shedding after intranasal challenge with a heterologous PRRSV-1-1 strain differ significantly.</p></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"180 ","pages":"Article 105416"},"PeriodicalIF":2.2,"publicationDate":"2024-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0034528824002832/pdfft?md5=4487ef95589da9ebbef05ed76549eec9&pid=1-s2.0-S0034528824002832-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142239404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Cleaning practices of transport vehicles by commercial and non-commercial livestock markets users in Scotland","authors":"Rebecca Allen ,&nbsp;Lisa A. Boden ,&nbsp;Ian Hutchinson ,&nbsp;Julie Stirling ,&nbsp;Thibaud Porphyre","doi":"10.1016/j.rvsc.2024.105413","DOIUrl":"10.1016/j.rvsc.2024.105413","url":null,"abstract":"<div><h3>Background</h3><p>Livestock markets are critical intermediaries in the movement of cattle and sheep between herds and to abattoirs. Disease prevention strategies promoting Cleansing &amp; Disinfection (C&amp;D) of vehicles moving animals from markets are in place in Scotland to reduce the risk of widespread transmission of pathogens within the livestock industry. However, little is known about how market users implement C&amp;D on their vehicles and how these may differ between sectors of the industry.</p></div><div><h3>Methods</h3><p>An online questionnaire was completed by 72 Scottish market users to investigate C&amp;D practices on livestock transport vehicles. Respondents were grouped based on their farming activities and biosecurity practices were compared between commercial and non-commercial users.</p></div><div><h3>Results</h3><p>The results showed a lower-than-expected use of brush or disinfectant and a shorter-than-expected time spent on C&amp;D. Particularly, 43.6 % of respondents spent less than 30 min to C&amp;D their vehicle, with no significant differences between respondents from commercial and non-commercial sectors (<em>P</em> = 0.75). Overall, we found little differences in C&amp;D practices and level of training between sectors, highlighting the industrywide deficit in biosecurity knowledge.</p></div><div><h3>Conclusions</h3><p>These results highlight a need to improve the messaging and awareness on good C&amp;D practices on transport vehicles. Regular training on C&amp;D practices is recommended, particularly for commercial livestock transport.</p></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"180 ","pages":"Article 105413"},"PeriodicalIF":2.2,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0034528824002807/pdfft?md5=575eb1cc626634b997326fad7cd45abd&pid=1-s2.0-S0034528824002807-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142173130","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An exploratory examination of the symptoms of moral injury and posttraumatic growth in veterinary professionals following exposure to potentially morally injurious events","authors":"C.E. Connolly,&nbsp;K. Norris","doi":"10.1016/j.rvsc.2024.105415","DOIUrl":"10.1016/j.rvsc.2024.105415","url":null,"abstract":"<div><p>Through their occupational role, veterinary professionals are regularly exposed to potentially morally injurious events (PMIEs). These events can elicit negative (pathogenic) psychological outcomes of moral distress. However, PMIEs can also result in positive (salutogenic) outcomes of posttraumatic growth. Both outcomes are characterised by specific symptomology that is suggestive of a pathogenic or salutogenic trajectory. This study employed data from 194 veterinary professionals from Australia and New Zealand and sought to examine symptoms experienced by professionals following exposure to PMIEs. Respondents reported more symptoms of moral distress than posttraumatic growth following PMIE exposure. Negative symptoms included both affective and work-related factors including consideration of leaving the profession, while positive factors included increased confidence, personal growth, and staff cohesion. Potential factors contributing to the disparity in salutogenic and pathogenic outcomes are discussed. An integrated approach comprising both individual- and organisation-level factors is recommended to facilitate more salutogenic outcomes for veterinary professionals following PMIE exposure.</p></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"180 ","pages":"Article 105415"},"PeriodicalIF":2.2,"publicationDate":"2024-09-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0034528824002820/pdfft?md5=beda8756ea6bbd528464aa0eb2fddc61&pid=1-s2.0-S0034528824002820-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142228688","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Disposition kinetics and bioavailability of doxycycline after parenteral administrations in ewes","authors":"José Martínez ,&nbsp;Elisa Escudero ,&nbsp;Elena Badillo ,&nbsp;María Teresa Yuste ,&nbsp;Juan Sebastián Galecio ,&nbsp;Pedro Marín","doi":"10.1016/j.rvsc.2024.105412","DOIUrl":"10.1016/j.rvsc.2024.105412","url":null,"abstract":"<div><p>Doxycycline is a tetracycline, which have been marketed in different species for treating infections caused by susceptible bacteria. There is limited information on the disposition kinetics of this drug in ewes and this antimicrobial may be useful against several sheep pathogens that are common causes of morbidity and economic loss. Therefore, the aim of this work was to establish the pharmacokinetics of doxycycline after intravenous (IV) and extravascular (subcutaneous (SC) and intramuscular (IM)) administrations in this species. A cross-over model was designed (<em>n</em> = 6). Doxycycline was dosed at 5 mg/kg for IV administration and 20 mg/kg for extravascular administrations. Non-compartmental pharmacokinetic methods were used to calculate plasma concentration-time data. The value of apparent volume of distribution (V_z) suggests a moderate distribution of this antibiotic in sheep, with a value of 0.84 L/kg. The maximum concentrations achieved after extravascular administrations (C_max) were similar, with no significant differences between the two routes of administration (IM and SC). However, doxycycline absorption was slower after SC administration than after IM administration, taking twice as long to reach maximum plasma concentration (t_max). Bioavailabilities after extravascular routes of administration were low and after IM administration doxycycline caused lameness in all animals. Therefore, the SC administration showed a better profile with respect to pharmacokinetic properties and safety. Future studies on the susceptibility of isolated sheep pathogens to doxycycline are needed to establish appropriate dosing regimens.</p></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"180 ","pages":"Article 105412"},"PeriodicalIF":2.2,"publicationDate":"2024-09-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0034528824002790/pdfft?md5=7af54166891496c0b4215d7a3edae9e0&pid=1-s2.0-S0034528824002790-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142167415","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Relationship between pharmacokinetics of fluazuron and its efficacy for controlling Rhipicephalus microplus: A comprehensive evaluation of tick drug uptake","authors":"Macarena Sarli ,&nbsp;María Victoria Miró ,&nbsp;María Victoria Rossner ,&nbsp;Viviana Gómez ,&nbsp;Jorgelina Torrents ,&nbsp;Santiago Nava ,&nbsp;Adrián Lifschitz","doi":"10.1016/j.rvsc.2024.105402","DOIUrl":"10.1016/j.rvsc.2024.105402","url":null,"abstract":"<div><p>Relationship between fluazuron (FZN) concentrations in cattle plasma and ticks and its therapeutic efficacy percentage (EP) against <em>Rhipicephalus microplus</em> was analyzed. The extent of FZN uptake by ticks after its topical administration was also evaluated. Heifers, naturally infested with <em>R. microplus</em>, were divided in treated and no treated groups. Blood and tick samples were taken to measure FZN concentrations and female ticks were counted to evaluate the EP of the treatment from day 0 to 45 post-treatment (PT). Ticks exposed (TE) and not exposed (TNE) to topical contact with the drug were collected at 12 and 24 h PT. Artificial feeding (AF) of ticks was also performed with blood from a treated heifer. The EP on days 21, 28, 35, 42 and 45 PT was 99.1, 92.3, 81.2, 74.7 and 76.5 %, respectively. Fluazuron disposition within ticks during the first 2 days post-treatment did not mirror the corresponding FZN levels in the bovine plasma, but a statistically significant positive correlation was evident from day 3. Mean FZN concentrations in TE at 12 h and 24 h PT were significantly higher than in TNE. The FZN concentrations in AF ticks were significantly lower than those in TE but comparable to the levels in TNE. The efficacy and pharmacokinetics analysis suggest that maintaining a threshold FZN plasma concentration above 20–25 ng/mL is crucial to prevent the development of larvae into engorged females. The results also indicate that direct absorption of FZN through the tick's integument occurs in the initial days after treatment.</p></div>","PeriodicalId":21083,"journal":{"name":"Research in veterinary science","volume":"180 ","pages":"Article 105402"},"PeriodicalIF":2.2,"publicationDate":"2024-09-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"142161652","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}