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Testing Mini-FLOTAC for the Monitorization of Gastrointestinal Parasitic Infections in Birds Kept at Four Iberian Zoological Institutions

Publication . Lozano, João; Pombo, Cándido; Salmo, Rami; Cazapal-Monteiro, Cristiana; Arias, María Sol; Carvalho, Daniela; Lordelo, Madalena; Batista, Augusto; Bernardino, Rui; Rinaldi, Laura; Oliveira, Manuela; Paz-Silva, Adolfo; Carvalho, Luís Madeira de

Birds kept in zoological institutions are highly exposed to gastrointestinal (GI) parasitism caused by coccidia and nematodes. The current research aimed to characterize the avian GI parasitic fauna in several zoological collections in Portugal and Spain. During the full year of 2022, a total of 120 fecal samples were collected from four zoological institutions: Lisbon Zoo, Olivais Pedagogical Farm, and Avian Biodiversity Center (Lisbon, Portugal), and Avifauna park (Lugo, Spain). Analysis was conducted in domestic bird species (autochthonous and exotic poultry breeds), and 18 differ- ent exotic bird species like Galliformes (peacock, pheasant), Anseriformes (duck), Psittaciformes (parrot, macaw, cockatiel, parakeet, cockatoo), Coraciiformes (motmot), Charadriiformes (avocet), Strigiformes (owl), Phoenicopteriformes (flamingo), Struthioniformes (ostrich), Rheiformes (rhea), and Casuariiformes (emu, cassowary). Feces were processed using Mini-FLOTAC (MF), to identify parasitic forms and quantify their shedding (oocysts or eggs per gram of feces). Moreover, 15 fecal samples from pheasants were also processed using the McMaster method (McM), to compare the parasite shedding and frequencies between techniques. MF implementation allowed identification of coccidia infections in all bird collections. Also, peacocks of the Lisbon Zoo tested positive for Trichostrongylus tenuis and Strongyloides pavonis, and the exotic birds from Avifauna park were also positive for several nematode species, with Ascaridia sp., Capillaria sp., Strongyloides sp., and Syngamus trachea eggs being detected in pheasants’ feces. Moreover, the analysis of pheasants’ feces with MF detected prevalences of 33% for coccidia oocysts, and 47% for Capillaria sp. and Ascaridia sp. eggs, while McM detected prevalences of 13%, 27%, and 40% for the respective parasite taxa, with no differences being observed between methods (p = 0.39, p = 0.45, and p = 0.50, respectively). This research provided more scientific support regarding the importance of using Mini-FLOTAC in routine parasitological diagnosis in birds kept at zoological institutions

2024-06Journal article

Open access

First evaluation of the use of phoxim as a contribute to the control of Gasterophilus intestinalis burden in horses at pasture : a pilot study

Publication . Rodrigues, Teresa Pimentel Serrano; Tilley, Paula Alexandra Botelho Garcia de Andrade Pimenta; Vitorino, Tomé António Fino (Tutor)

ABSTRACT - Gasterophilus intestinalis, also known as horse bot fly is a well-known parasite by horse owners. During spring and summer, the female insect lays up to 1000 eggs onto the coat of the horse, mainly in the frontlimbs. Phoxim is an organophosphate insecticide that acts by specifically inhibiting the enzyme acetylcholinesterase irreversibly. The objective of this study was to evaluate the feasibility and efficacy of utilising topical phoxim as a therapeutic strategy to reduce the egg load of G. intestinalis in horses under field conditions. This approach was designed to disrupt the parasite's life cycle before it is ingested and infects the horse. The reduction in the survival of G. intestinalis larvae in the treatment group and the impact of treatment on larval mortality over time were investigated. The study was carried out on fourteen purebred Lusitano horses, in Ribatejo, Portugal. Two groups of samples were formed with fourteen horses each. The samples were taken from the front limbs. The first group, the control group, included fourteen hair samples taken on the first day before the treatment was applied. The second group, being the treatment group, included the hair samples taken twenty-four hours after the application of phoxim, to the fourteen horses. All individual horses belonged both to the control and treatment group. The treatment solution was prepared by adding one millilitre of Byemite® (500 mg phoxim/mL) to one liter of water at forty degrees Celsius. The samples were observed under a stereo microscope, and the evolution of the eggs was analysed on days 1, 3, 7 and 10. The findings on the evolution of egg counts, live and dead larvae over time were consistent with the efficacy of phoxim treatment. It became evident that the number of eggs in the treatment group remained the same since the larvae had died, while the number of live larvae decreased, and the number of dead larvae increased over those days. This pilot study reveals some preliminary data that may contribute to the future inclusion of phoxim as an effective means of controlling G. intestinalis, particularly in Mediterranean climates. The observed alterations in eggs and larvae following treatment emphasize the necessity for further research, which could prove instrumental in preventing digestive issues concerning these parasites

2024-12-17Master thesis

Open access

Sharing more than friendship : dynamics of direct transmission of antimicrobial resistance between human families and their companion animals

Publication . Menezes, Juliana Cruz de Oliveira de; Pomba, Maria Constança Matias Ferreira; Fonseca, Andreia de Jesus Amaral Gomes Barbosa

Enterobacterales that produce extended-spectrum β-lactamases (ESBLs), AmpC cephalosporinases and carbapenemases (CPE), as well as colistin-resistant strains, are important pathogens raising public health concerns due to their increasing prevalence. The prospective longitudinal study focusing on households in Portugal (PT) and the United Kingdom (UK), showed that ESBL/AmpC-producing Enterobacterales strains carriage in healthy companion animals occur at a significantly lower frequency (p-value <0.0001) compared to animals with active infections under antibiotic therapy. Whole genome sequencing (WGS) analysis identified the sharing of ESBL/AmpC-producing Enterobacterales strains between healthy companion animals and humans in two households from Portugal (n=41), involving Escherichia coli human pandemics lineages ST93, ST410 and ST457. Among companion animals undergoing antibiotic treatment due to urinary tract infection (UTI) or skin and soft tissue infection (SSTI), and their cohabiting humans, sharing of faecal ESBL/AmpC producing E. coli strains was observed in four households (PT= 2/43; UK= 2/22), with strains belonging to ST2015, ST617 and ST963. Additionally, one Portuguese household shared a multidrug-resistant (MDR) ACT-24-producing Enterobacter hormaechei subsp. hoffmannii strain. Notably, three other animals shared the clinical strains with their cohabiting humans: a ST556 Klebsiella pneumoniae, the high-risk clonal lineage ST131 E. coli strain and a ST2179 E. coli classified as Avian Pathogenic (APEC). CPE strains were only detected in animals under antibiotic treatment. These strains were positive for blaOXA-181 and blaNDM-5 genes, present in plasmids virtually identical to those found in isolates from humans, food, and the environment in other countries. MDR E. coli strains harbouring the plasmid-mediated colistin resistant gene, mcr-1, were recovered from faecal samples of companion animals and humans in Portugal, with no significant difference between healthy and infected groups (p-value=0.257). In two households with dogs diagnosed with SSTIs, sharing of mcr-1-positive ST744 E. coli strains with the owner were observed. The detection of MDR bacteria sharing between companion animals and their cohabiting humans, especially when it matched the animal's UTI/SSTI clinical strain, highlights the importance of considering household-level interventions in response to the spread of antimicrobial resistance in the community, reinforcing the need for active monitoring and stringent hygiene practices under a One Health approach

2025-02-28Doctoral thesis

Open access

Effects of high dietary inclusion of Arthrospira platensis, either extruded or supplemented with a super-dosing multi-enzyme mixture, on broiler growth performance and major meat quality parameters

Publication . Costa, Mónica M.; Spínola, Maria P.; Tavares, Beatriz; Pestana, José M.; Tavares, João C.; Martins, Cátia F.; Alfaia, Cristina M.; Carvalho, Daniela; Mendes, Ana R.; Ferreira, Joana I.; Mourato, Miguel; Lordelo, Madalena; Prates, José A. M.

Background This investigation assessed the effects of high dietary inclusion of Spirulina (Arthrospira platensis) on broiler chicken growth performance, meat quality and nutritional attributes. For this, 120 male broiler chicks were housed in 40 battery brooders (three birds per brooder). Initially, for 14 days, a standard corn and soybean meal diet was administered. Subsequently, from days 14 to 35, chicks were assigned to one of the four dietary treatments (n = 10 per treatment): (1) control diet (CTR); (2) diet with 15% Spirulina (SP); (3) diet with 15% extruded Spirulina (SPE); and (4) diet with 15% Spirulina plus a super-dosing enzymes supplement (0.20% pancreatin extract and 0.01% lysozyme) (SPM). Results Throughout the experimental period, both SP and SPM diets resulted in decreased final body weight and body weight gain compared to control (p < 0.001), with the SPE diet showing comparable results to CTR. The SPE diet prompted an increase in average daily feed intake (p = 0.026). However, all microalga treatments increased the feed conversion ratio compared to CTR. Dietary inclusion of Spirulina notably increased intestinal content viscosity (p < 0.010), which was mitigated by the SPM diet. Spirulina supplementation led to lower pH levels in breast meat 24 h post-mortem and heightened the b* colour value in both breast and thigh meats (p < 0.010). Furthermore, Spirulina contributed to an increased accumulation of total carotenoids, n-3 polyunsaturated fatty acids (PUFA), and saturated fatty acids (SFA), while diminishing n-6 PUFA, thus altering the n-6/n-3 and PUFA/SFA ratios favourably (p < 0.001). However, it also reduced zinc concentration in breast meat (p < 0.001).Conclusions The findings indicate that high Spirulina levels in broiler diets impair growth due to increased intestinal viscosity, and that extrusion pre-treatment mitigates this effect. Despite reducing digesta viscosity, a super-dosing enzyme mix did not improve growth. Data also indicates that Spirulina enriches meat with antioxidants and n-3 PUFA but reduces α-tocopherol and increases saturated fats. Reduced zinc content in meat suggests the need for Spirulina biofortification to maintain its nutritional value.

2024-05Journal article

Open access

Integrated transcriptomics and proteomics analysis reveals muscle metabolism effects of dietary Ulva lactuca and ulvan lyase supplementation in weaned piglets

Publication . Ribeiro, David Miguel; Coelho, Diogo; Costa, Mónica; Carvalho, Daniela; Leclercq, Céline C.; Renaut, Jenny; Freire, João; Almeida, André; Prates, José António Mestre

Seaweeds, including the green Ulva lactuca, can potentially reduce competition between feed, food, and fuel. They can also contribute to the improved development of weaned piglets. However, their indigestible polysaccharides of the cell wall pose a challenge. This can be addressed through carbohydrase supplementation, such as the recombinant ulvan lyase. The objective of our study was to assess the muscle metabolism of weaned piglets fed with 7% U. lactuca and 0.01% ulvan lyase supplementation, using an integrated transcriptomics (RNA-seq) and proteomics (LC–MS) approach. Feeding piglets with seaweed and enzyme supplementation resulted in reduced macronutrient availability, leading to protein degradation through the proteasome (PSMD2), with resulting amino acids being utilized as an energy source (GOT2, IDH3B). Moreover, mineral element accumulation may have contributed to increased oxidative stress, evident from elevated levels of antioxidant proteins like catalase, as a response to maintaining tissue homeostasis. The upregulation of the gene AQP7, associated with the osmotic stress response, further supports these findings. Consequently, an increase in chaperone activity, including HSP90, was required to repair damaged proteins. Our results suggest that enzymatic supplementation may exacerbate the effects observed from feeding U. lactuca alone, potentially due to side effects of cell wall degradation during digestion.

2024-02Journal article

Open access