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This paper presents a comprehensive comparison of the phase control (PC) and time-proportional control (TPC) schemes, which are commonly used for power control of alternating current (AC) loads with alternating current triodes (TRIACs). Although these control schemes have already been individually studied, our work aims to extend the comparisons in terms of spectral content, quality metrics, and electromagnetic compatibility (EMC), considering both theoretical and experimental perspectives, for residential applications. Based on the obtained results, it was verified that the TPC exhibits better characteristics than the PC scheme. Therefore, the TPC scheme becomes a viable alternative for controlling higher power loads while complying with the requirements established in the IEC 61000-3-2, CISPR 11, and IEC 61000-3-3 standards. [ABSTRACT FROM AUTHOR]

We aim to describe the parasitic population in vicuñas from three Andean communities and its relationship with fiber quality using 115 fecal and 22 fiber samples, classified according to sex, age, body condition score, and management system. Coproparasitologic diagnostic revealed that 84.4% of animals presented at least one type of parasite egg/oocyst. Most frequent parasite egg/oocyst were Strongyle-type eggs (54.8%) and Eimeria punoensis (38.3%). Wild vicuñas had a higher prevalence of Strongyle-type eggs (91.4%) than semi-captive (38.8%) animals, and age was significative to Eimeria infection; crias had the highest frequency (100%) when compared to yearlings (84.2%) and adults (49.4%). Larvae identification revealed a strong influence of domestic animals on vicuña parasite community, presenting the first report of Bunostomum phlebotomum and Gaigeria pachyscelis in vicuñas from southeastern Peru. Females had a significantly finer diameter of fiber (13.05 ± 0.73 μm) than males (14.22 ± 1.22 μm), and infection with Eimeria spp. affected negatively fiber diameter and resistance. Our results provide data for disease surveillance and encourage further parasitological studies in vicuñas. [ABSTRACT FROM AUTHOR]

Bovine cysticercosis (BCC) is the most frequently detected zoonosis in Brazilian slaughterhouses and is considered a problem for public health and beef production chain, requiring epidemiological studies focusing on evaluating its prevalence, spatial distribution, and economic losses in order to improve and adopt specific strategies for BCC control. Thus, this study focused to establish BCC prevalence and spatial distribution in the state of Rio Grande do Sul, Brazil, and estimate the economic losses for cattle farmers suppliers of one exporter slaughterhouse. A set of 70,591 bovine carcasses were postmortem inspected from 2019 to 2020, which came from 134 municipalities located in eight distinct regions in the state of Rio Grande do Sul. The prevalence found was 3.44% (C.I. 95% 3.30–3.57%), and animals infected with unviable cysticerci were more frequently detected (70.56%) than those carrying viable ones (29.44%). The most frequent destination of carcasses and viscera was non-export (65.48%), followed by freezing/salting (25.41%), heat treatment (8.74%), and rendering (0.37%), resulting in a total economic burden of at least US$ 167,868.53 for cattle farmers. Some regions had higher risk for BCC occurrence, such as Porto Alegre, Caxias do Sul, Santa Maria, Ijuí, and Passo Fundo (OR > 1, p < 0.05), respectively. These results highlight the need of adopting prophylactic measures, mainly in specific areas, in order to control BCC and reduce the economic losses for beef production chain. [ABSTRACT FROM AUTHOR]

Bovine viral diarrhea virus (BVDV) infects ruminants as primary hosts. However, other animals like pigs are susceptible. This study was conducted to investigate seroprevalence and risk factors associated with the detection of BVDV antibodies in pig herds. A total of 1.705 serum samples of 33 finisher herds, from seven Brazilian states, were collected in slaughterhouses. The samples were tested by virus neutralization (VN) test. In total, 5.35% (91/1.705) were positive and 64% (21/33) of the herds had positive animals. A significant association with “trucks are not cleaned and disinfected” and “visitors do not respect 72-h interval between visits to farms” (P < 0.05) was found in association with detection of BVDV-2 antibodies. This study suggests that important biosecurity gaps are present in Brazilian pig farms, as the presence of BVDV antibodies in pigs suggests (direct or indirect) contact with population(s) of ruminant species. Closing biosecurity gaps prevents spread of BVDV and other pathogens such as foot-and-mouth disease virus (FMDV) between pig and ruminant farms. This data should be taken in account by CSF surveillance programs, once cross-reaction in serologic tests between classical swine fever virus (CSFV) and BVDV antibodies has been shown to occur. [ABSTRACT FROM AUTHOR]

Swine influenza (SI) is a seasonal infectious disease highly important to the world pig industry. Loss of daily weight gain, increased costs for the prevention and treatment of secondary infections are the main economic losses associated with the presence of this disease. However, some epidemiological features of SI remain quite unclear. This study focused on assessing the prevalence of swine influenza virus (SIV) infection in intensive and extensive pig herds and associating risk factors. A set of 601 blood samples of five intensive farrow-to-finish farms and 361 blood samples from 56 extensive farms were analyzed using an indirect ELISA kit CIVTEST SUIS INFLUENZA®, Hipra (Amer, Spain), in order to detect anti-SIV antibodies. In total, 24.13 % of samples from intensive herds were positive, while no positive samples were detected in extensive rearing herds. Sow and weaning piglets had the highest prevalence values. In the intensive rearing system, occurrence of reproductive disorders and exposure to recently introduced animals were positively associated with the disease occurrence in swine herds. The findings highlight the importance of sows in the epidemiology of the disease and bring information about risk factors involved in the occurrence of swine influenza in intensive herds. [ABSTRACT FROM AUTHOR]

Brucella suis has been recognized as the major etiological agent of human brucellosis in areas free from Brucella melitensis infection. However, with changes in swine management, the occurrence of swine brucellosis has decreased as has the human incidence of B. suis infection. A swine brucellosis outbreak within a herd from Jaboticabal (São Paulo, Brazil) was detected in July 2006. The herd comprised approximately 300 sows and 1,500 finishing animals. Many sows within this herd experienced abortions, while others exhibited vaginal discharge; three sows suffered posterior paralysis. Among 271 sows, 254 (93.7%) tested positive for brucellosis by complement fixation, and among 62 randomly bled finishing animals, 17 (27.4%) also tested positive. The B. suis biovar 1 was cultured from 14 aborted fetuses and six sows. Brucella was identified using routine methods. Fourteen farm workers were tested using agglutination tests, with three workers showing evidence of Brucella antibody titers. A 39-year-old woman, who worked with maternal pigs and had direct contact with aborted fetuses, presented an agglutinating titer of 480 IU/mL and displayed clinical signs of infection. Our findings suggest that despite a reduction of swine brucellosis throughout Brazil, B. suis infection still occurs, thereby posing a zoonotic risk. [ABSTRACT FROM AUTHOR]