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Feline coronavirus (FCoV) is an important virus that can be differentiated into two serotypes: feline enteric coronavirus (FECoV) and feline infectious peritonitis (FIP) virus (FIPV). Researchers have suggested that a mutation of FECoV to FIPV leads to the emergence of FIP, a disease with worldwide distribution and a high mortality rate. Furthermore, in December 2019, a human infectious disease, coronavirus disease-2019 (COVID-19), which is also caused by a coronavirus (severe acute respiratory syndrome coronavirus 2 [SARS-CoV-2]) emerged, and clarity regarding its relationship with FCoV remains lacking. Studies have shown that cats are susceptible to infection with this novel coronavirus (i.e., SARS-CoV-2). The aim of the present study was to detect and semi-quantify the presence of feline antibodies to FIPV in cats examined at the Veterinary Hospital of Santa Cruz State University, microregion of Ilhéus and Itabuna, Bahia, Brazil, between January and April 2018. Blood samples were collected from 68 domestic cats to perform complete blood count (CBC) and biochemical tests, and an indirect fluorescent antibody test (IFAT) was used to detect FCoV infection. Of the 68 samples evaluated, seropositivity was observed in 4.4% (3/68) at titers of 1:20; only one sample remained seropositive at titers of 1:40 and 1:80. Two positive animals exhibited CBC and biochemical values within the normal range, while the other positive animals exhibited a mild decrease in platelet count (173,000 uL-1), mild lymphocytosis (7395 uL-1), and mildly increased alkaline phosphatase level (134 uL-1). Twelve months after the tests, none of the positive animals exhibited clinical signs consistent with FIP. Although the IFAT can facilitate diagnosis of FPIV, it cannot be used to differentiate antibodies for the FECoV and FIPV serotypes. Results of the present study demonstrated that FCoV was present in the population studied, and is an important risk factor for the development of FIP. In addition, the new COVID-19 pandemic highlights the importance of studies investigating FCoV because it was not possible to rule out, until now, the possibility of FCoV mutations in infected cats if it encounters SARS-CoV-2.

The aims of this study were to determine the seroprevalence of Sarcocystis neurona antibodies in equines in the Ilhéus-Itabuna microregion (BA), and identify possible factors associated with infection. The presence of sporocysts/oocysts of Sarcocystis spp. was also verified in Didelphis spp. A total of 669 serum samples were collected from equines in 56 properties located in 12 municipalities in the region. Indirect fluorescent antibody test was performed with slides containing merozoites of the S. neurona, using a cut-off titer of 1:80. Occurrence of 7.92% of anti-S. neurona antibodies was observed in the sampled equines. The purposes trade and work were significantly associated with the presence of antibodies (p

The objectives of this study were to evaluate the dry matter intake (DMI), digestibility, average daily gain (ADG), microbial efficiency, empty body weight (EBW) gain, and body composition of Nellore bulls. Additionally, Nellore bull maturity was estimated, and the prediction equation for DMI, suggested by the Brazilian nutrient requirements system (BR CORTE; Azevêdo et al. 2010), was evaluated. Thirty-three Nellore bulls, with a mean initial weight of 259 ± 25 kg and age of 14 ± 1 months, were used in this study. Five animals were slaughtered at the beginning of the experiment (control group), and the remaining 28 were divided into 4 groups, each slaughtered at 42-day intervals. Their diet was composed of corn silage and concentrate (55:45). The power model was used to estimate muscle tissue, bone tissue, crude protein (CP), mineral matter (MM), and water present in the empty body, while the exponential model was used to estimate adipose tissue and ether extract (EE) present in the empty body. When expressed in kilograms per day, differences were observed (P 0.05) digestibility, with the exception of EE digestibility. The equation suggested by BR CORTE correctly estimates the DMI of Nellore bulls. ADG was not affected (P > 0.05) by time spent in the feedlot. No differences were observed (P > 0.05) for microbial efficiency; a mean value of 142 g microbial crude protein/kg total digestible nutrients was achieved. The muscle and bone tissues, CP, MM, and water present in the empty body increased as the animal grew, although at a lower rate. The adipose tissue and EE present in the empty body increased their deposition rate when the animal reached its mature weight. Maturity is defined as when an animal reaches 22 % EE in the empty body, which corresponds to 456 kg of EBW in Nellore bulls. Therefore, this study can conclude that the feedlot time period does not affect DMI, nutrient intake, ADG, or microbial efficiency. The equation proposed by BR CORTE (Azevêdo et al. 2010) correctly estimates the DMI of Nellore bulls, which reach maturity when an EBW of 456 kg is attained.

The objectives of this experiment were to estimate the endogenous excretion of purine derivatives (PD), the intake and digestibility of nutrients, the urinary excretion of PD from the intake of total digestible nutrients (TDN) and digestible organic matter (DOM) in Nellore heifers. Eight heifers, 267±17 kg body weight (BW), were assigned to two 4 × 4 latin squares. The planned treatments were four dry matter intake (DMI) levels: 10, 14, 18 and 22 g/kg BW. The diet contained 70% corn silage and 30% concentrate. The endogenous losses were obtained by regression between excretion of PD (mmol/BW0.75) and DMI (g/BW0.75). When PD excretion (mmol/d) was related to the intake of DOM and TDN (kg/d), the following equations were obtained: ŶPD= 32.98 + 21.94*DOM and ŶPD= 32.47 + 20.40*TDN, respectively. The excretion of PD (mmol/d) was a function of DMI (kg/d): ŶPD = 0.605 + 0.014 x (r² = 0.46), and 0.60 mmol/BW0.75 was the endogenous fraction of PD. The endogenous losses of PD and nitrogen compounds obtained when the animals were fasted for 5 d, with free access to water, were 0.332 mmol/BW0.75 and 0.384 gN/BW0.75, respectively. The net protein requirement for maintenance was estimated at 2.4 g/BW0.75. Creatinine excretion is not affected by feed restriction.