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- Targeted-Amplicon NGS for Blastocystis sp. in Shepherd Dogs of Portugal Discriminates Co-Colonization with Multiple Zoonotic SubtypesPublication . Gomes-Gonçalves, Sara; Feiteiro, Maria João; Moreira, Guilherme; Cruz, Rita; Esteves, Fernando; Vala Correia, Helena Maria; Mesquita, João R.Research on endoparasites in pet dogs has been growing, but shepherd dogs have largely been overlooked. These dogs frequently share close proximity not only with sheep, which are reservoirs of zoonotic subtypes of Blastocystis, but also with their owners. This close contact increases the potential for shepherd dogs to act as intermediates in the transmission of Blastocystis. To clarify the role of these dogs as reservoirs for this parasite, this study investigated the presence of Blastocystis in shepherd dogs. Stool samples from Portuguese shepherd dogs were analyzed using SYBR-Green-based real-time PCR and melting curve analysis followed by targeted-amplicon NGS for mixed infections detection. Our results revealed a 60% occurrence of Blastocystis sp. in shepherd dog stools and frequent identification of zoonotic subtypes ST1–ST4 and ST14. Additionally, we observed mixed infections and subtype diversity within individual dogs, suggesting a potential role in cross-species transmission between livestock and humans.
- Molecular Screening of Sarcocystis spp. in Grazing Sheep (Ovis aries) and Shepherd Dogs (Canis lupus familiaris) from Central PortugalPublication . Gomes-Gonçalves, Sara; Figueiredo, Ricardo J.; Rodrigues, Soraia; Bento, Jaqueline T.; Santos-Silva, Sérgio; Almeida, Daniela; Cruz, Rita; Esteve, Fernando; Esteves, Fernando; Baptista, Alexandra Lameira; Pereira, Maria Aires; Cardoso, Luís; Mesquita, João R.Sarcocystis spp. are cyst-forming protozoan parasites with a global distribution that infect a wide range of domestic and wild animals, impacting both animal health and livestock productivity. In sheep, infections can cause clinical disease, reproductive losses, and economic damage, articularly when pathogenic species such as Sarcocystis tenella are involved. Grazing sheep, including breeds such as the Serra da Estrela from central Portugal, are at increased risk due to frequent contact with shepherd dogs, which serve as definitive hosts. Despite their significance, data on the occurrence and distribution of Sarcocystis spp. in Portuguese sheep remain limited. This study analyzed 179 samples collected in central Portugal during 2024, including 41 brain tissues and 88 blood samples from sheep, and 50 stool samples from shepherd dogs, using conventional PCR and bidirectional Sanger sequencing. Sarcocystis sp. closely related to S. tenella was detected exclusively in sheep brain tissue, with a prevalence of 4.9% (2/41; 95% CI: 0.60–16.53), while no parasite DNA was found in blood or dog samples. These results provide the first molecular confirmation of Sarcocystis spp. closely related to S. tenella in Portuguese sheep raised for human consumption and establish baseline data for future epidemiological surveillance and control strategies.
- Toxoplasma Gondii In Shepherds and Cheesemakers – A Case-Control Study on Sheep-Associated Occupational Exposure in Central PortugalPublication . Moreira, Guilherme; Almeida, Daniela; Cruz, Rita; Nóbrega, Carmen; Arede dos Santos, Carla Sofia; Coelho, Catarina; Mega, Cristina; Pereira, Maria; Esteves, Fernando; Vala Correia, Helena Maria; Cardoso, Luís; Lopes, Ana P.; Coelho, Ana C.; Mesquita, João R.Objectives: The primary objective of this study was to determine if workers occupationally exposed (WOE) to sheep, specifically shepherds and cheesemakers in central Portugal, are more likely to be seropositive for anti-Toxoplasma gondii IgG compared to the general population. Additionally, the study aimed to explore potential differences in seropositivity between shepherds and cheesemakers, while evaluating age, gender, and activity as possible risk factors for T. gondii infection. Methods: A total of 96 WOE, including 21 shepherds and 75 cheesemakers, were tested for anti-T. gondii IgG using a commercial enzyme-linked immunosorbent assay (ELISA). The control group consisted of 192 sera samples from blood donors matched by age, gender, and residence. Chi-square tests with Yates correction were used to compare seroprevalence between WOE and the general population, and between shepherds and cheesemakers. Univariate and multivariable logistic regression analyses were performed to evaluate potential associations between T. gondii seropositivity and factors such as activity, gender, and age. Results: The overall seroprevalence was 63.5% in the WOE and 52.6% in the general population, with no statistically significant difference (p = .101). Among WOE, 52.4% of shepherds and 66.7% of cheesemakers were seropositive, with no significant difference between the two groups (p = .344). Univariate and multivariable analyses indicated neither activity, age, nor gender were significant risk factors for seropositivity in the case population. Conclusion: The study did not find a significant increased risk of T. gondii seropositivity among shepherds and cheesemakers compared to the general population. While high seroprevalence was observed in both groups, other factors unrelated to occupational exposure may be influencing the risk of T. gondii infection. More research is needed, particularly focusing on cheesemakers, to further explore potential occupational health risks related to T. gondii.
- Assessing Q Fever Exposure in Veterinary Professionals: A Study on Seroprevalence and Awareness in Portugal, 2024Publication . Guilherme Moreira; Mário Ribeiro; Miguel Martins; José Maria Cardoso; Esteves, Fernando; Sofia Anastácio; Sofia Duarte; Vala Correia, Helena Maria; Cruz, Rita; Mesquita, João R.Due to their frequent contact with animals, veterinarians may be at preferential risk of Coxiella burnetii exposure due to occupational contact with livestock. This study assesses the seroprevalence and risk factors associated with C. burnetii seropositivity in Portuguese veterinarians. A cross-sectional study compared IgG anti-C. burnetii in veterinarians’ sera to a demographically matched control group. Univariate and multivariate logistic regression analyses evaluated associations between the demographic, occupational, and biosecurity factors and seropositivity. Seroprevalence among veterinarians was 33.7%, significantly higher (p = 0.0023) than in the controls (17.39%). Univariate analysis identified higher seropositivity in the northern region (p = 0.03), though this association was not significant after adjustment (p = 0.07). Protective measures, including isolating aborting animals from the rest of the herd (adjusted OR [aOR]: 0.35, p = 0.03) and wearing gloves during sample collection (OR: 0.28, p = 0.009), were significantly associated with lower infection risk. Veterinarians face increased C. burnetii exposure, but specific biosecurity practices reduce risk. Strengthening preventive measures, including personal protective equipment (PPE) use and biosecurity training, is essential to mitigate occupational and public health risks. Further research should explore vaccination strategies and molecular epidemiology to improve risk reduction efforts.
- Integrated Soil Management: Food Supply, Environmental Impacts, and Socioeconomic FunctionsPublication . Pereira, José Luís da Silva; Pereira Domingues Martinho, Vítor JoãoThis Editorial refers to the Special Issue “Integrated Soil Management: Food Supply, Environmental Impacts, and Socioeconomic Functions”. The Special Issue highlights bringing a broader perspective on soil management, namely in its relationship with food supply, environmental dimensions, and socioeconomic activities. From a total of twenty-six manuscripts submitted for consideration and peer review, fourteen were accepted for publication and inclusion in this Special Issue (two reviews and twelve articles). The published contributions are listed below followed by a description review to encourage the reader to explore them.
- Targeted-Amplicon NGS for Blastocystis sp. in Shepherd Dogs of Portugal Discriminates Co-Colonization with Multiple Zoonotic SubtypesPublication . Sara Gomes-Gonçalves; Maria João Feiteiro; Guilherme Moreira; Rita Cruz; Fernando Esteves; Helena Vala; João R. Mesquita; Cruz, Rita; Esteves, Fernando; Vala Correia, Helena Maria
- Greenhouse Gas Emissions and Ryegrass Yield after Application of Solid-Liquid Pig Slurry and Biochar to an Agricultural SoilPublication . Pereira, José Luís da Silva; Perdigão, Adelaide; Bonifácio, Gabriel; Figueiredo, Vitor; Marques, Francisco; Trindade, Henrique; Ferreira Wessel, DulcineiaBackground: The application of animal slurry to the soil improves its quality, as manure contains many nutrients for plants. However, this could negatively impact the environment. Objective: This field study investigated the effects of the addition of biochar after the mechanical separation of Whole pig Slurry (WS) into Solid (SF) and Liquid Fractions (LF) on Greenhouse Gases (GHG) emissions (N2O, CO2, and CH4) and ryegrass (Lolium multiflorum Lam. cv magnum) yield. Methods: Biochar (1.0 kg m-2) was applied in plots alone or together with each of the three slurries (80 kg N ha-1) in a total of eight treatments with three replications, including just soil with and without biochar as controls. Soil properties, Greenhouse Gas (GHG) fluxes, and yield were measured during theautumn/winter growing season. Results: The results showed that the addition of biochar to these three slurries significantly increased the soil pH and showed no impact on the other physicochemical properties. The GHG emissions were not significantly different between treatments with and without biochar. The N use efficiency increased significantly in SF > WS > LF, whereas no differences were observed among these three slurries with and without biochar. Conclusion: It can be concluded that the addition of biochar combined with WS or SF/LF to sandy-loam soil appears to have no impact on GHG emissions and ryegrass yield during the autumn/winter season. Overall, this finding suggests that amounts higher than 1.0 kg m-2 of biochar combined with SF may need to be applied to soil to reduce GHG emissions and nitrate leaching and increase N use efficiency and crop yield
- Production and characterization of powder from drone brood of honeybees (Apis mellifera)Publication . Goncalves, J. C.; Vouga, Beatriz; Costa, Cristina Amaro Da; Gonçalves, Fernando Jorge; Coelho, Catarina; Guiné, Raquel; Correia, PaulaDrone bee brood are a natural source of food with potential for human nutrition. This work aims to investigate the production and extraction of the drone bee brood (larvae and pupae), as well as the production of powder from this insect for food applications. To produce the drone brood (DB), in some hives of the colony appropriate empty frames were placed. Some measurements were done in the hive to monitor the global wellbeing of the colony, namely, temperature, relative humidity, and weight. After approximately one month, the frames were removed from the hives and frozen. The yield of DB by frame was 38%. For the extraction of the drone brood, different methods were tested, being the best ones the cold room extraction (∼ 6.5 °C), on a cold surface extraction (∼ 11 °C), and in boiling water extraction (100 °C). The results show that the extraction efficiencies were 74.3% (336.3 s), 62.5% (246.8 s) and 84.9% (332.0 s), for extraction in a cold room, on a cold surface, and in boiling water, respectively. After extraction, two drying processes were tested: evaporation and freeze-drying, being the last one the recommended, preserving in a better way the appearance and composition of the DB. DB powders presented different colour characteristics according to the extraction method used. The powder obtained by boiling extraction was darker than the one produced with cold extraction. Powders are rich in protein, fat and carbohydrates, being the fat content quite high for DB powders produced by boiling extraction method.
- Exploring the Potential of Machine Learning Algorithms Associated with the Use of Inertial Sensors for Goat Kidding DetectionPublication . Gonçalves, Pedro; Marques, Maria do Rosário; Belo, Ana Teresa; Monteiro, António; Morais, João; Riegel, Ivo; Braz, FernandoThe autonomous identification of animal births has a significant added value, since it enables for a prompt timely human intervention in the process, protecting the young and the mothers’ health, without requiring continuous human surveillance. Wearable inertial sensors have been employed for a variety of animal monitoring applications, thanks to their low cost and the fact that they allow less invasive monitoring process. Alarms triggered by the occurrence of events must be generated close to the events to avoid delays caused by communication latency, which is why this type of mechanism is typically implemented at the network’s edge and integrated with existing auxiliary mechanisms on the Internet. Although the detection of births in cattle has been carried out commercially for some years, there is no solution for small ruminants, especially goats, where the literature does not even report any attempts. The current work consisted of a first attempt at developing an automatic birth monitor using inertial sensing, as well as detection techniques based on Machine Learning, implemented in a network edge device to assure real-time alarm triggering. Thus, two concept drift detection techniques and seven kidding detection mechanisms were developed using data classification models. The work also includes the testing and comparison of learning results, both in terms of accuracy and of computational costs of the detection module, for algorithms implemented. The results revealed that, despite their simplicity, concept drift algorithms do not allow kidding detection, whereas classification-algorithm-based static learning models do, despite the unbalanced character of the dataset and its reduced size. The learning findings are quite promising in terms of computational cost and its suitability for deployment on edge devices. The algorithm demonstrates behavior changes four hours before kidding and allows for the identification of the kidding hour with an accuracy of 61%, as well as the capacity to improve the overall learning process with a larger dataset
- Biochar as an Alternative Litter Additive to Mitigate Gaseous Emissions from Broiler Housing and Subsequent StoragePublication . Pereira, José L.S.; Martins, Filipa; Bonifácio, Gabriel; Garcia, Carla; Teixeira, José; Trindade, HenriqueBroiler farming is a significant source of gaseous emissions. The aim of this study was to assess the effects of different litter additives on the emission of NH3, N2O, CO2, and CH4 during broiler housing and subsequent manure storage. The gaseous emissions from the housing facilities were evaluated during one fattening cycle in environmentally controlled rooms with three different additives applied to the litter material (10% w/w aluminum sulphate or biochar and 2.50 mg m−2 urease inhibitor), as well as a control. A storage experiment was conducted under laboratory conditions for 90 days to evaluate the influence of these three additives on gaseous losses. During broiler housing, the results indicated that NH3 emissions were reduced significantly (40–60%) by litter additives, while global warming potential (GWP) emissions were reduced significantly (31%) by Alum. The addition of Biochar (a 58% reduction) had the same significant effect as Alum (a 60% reduction) to mitigate these losses. The re-application of Urease (a 41% reduction) may be required to reach an equal or higher reduction. During storage, NH3 and GWP emissions were not significantly affected by the litter additives. During broiler housing and subsequent manure storage, NH3 emissions were reduced significantly (22–41%) by litter additives, whereas GWP emissions did not decrease significantly. Globally, it can be concluded that Biochar appears to be a good alternative to Alum due to its equal effectiveness in mitigating NH3 losses, without increasing the GWP potential in the housing and avoiding pollution swapping.