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The infection caused by porcine epidemic diarrhea virus (PEDV) is associated with high mortality in piglets worldwide. Host factors involved in the efficient replication of PEDV, however, remain largely unknown. Our recent proteomic study in the virus-host interaction network revealed a significant increase in the accumulation of CALML5 (EF-hand protein calmodulin-like 5) following PEDV infection. A further study unveiled a biphasic increase of CALML5 in 2 and 12 â€‹h after viral infection. Similar trends were observed in the intestines of piglets in the early and late stages of the PEDV challenge. Moreover, CALML5 depletion reduced PEDV mRNA and protein levels, leading to a one-order-of-magnitude decrease in virus titer. At the early stage of PEDV infection, CALML5 affected the endosomal trafficking pathway by regulating the expression of endosomal sorting complex related cellular proteins. CALML5 depletion also suppressed IFN-ß and IL-6 production in the PEDV-infected cells, thereby indicating its involvement in negatively regulating the innate immune response. Our study reveals the biological function of CALML5 in the virology field and offers new insights into the PEDV-host cell interaction.

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Tripartite motif-containing proteins (TRIMs), exhibiting ubiquitin E3 ligase activity, are involved in regulation of not only autophagy and apoptosis but also pyrotosis and antiviral immune responses of host cells. TRIMs play important roles in modulating signaling pathways of antiviral immune responses via type I interferon, NF-κB, Janus kinase/signal transducer and activator of transcription (JAK/STAT), and Nrf2. However, viruses are able to antagonize TRIM activity or evenly utilize TRIMs for viral replication. This communication presents the current understanding of TRIMs exploited by viruses to evade host immune response.

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Pigeon paramyxovirus type I (PPMV-1) causes regular outbreaks in pigeons and even poses a pandemic threat among chickens and other birds. The birds infected with PPMV-1 mainly show a pathological damage in the respiratory system, digestive system, and nervous system. However, there were few reports on the efficiency of the virus entering the host via routes of different systems. In the present study, a PPMV-1 strain was obtained from a dead wild pigeon in 2016 in Beijing, China. The mean death time (MDT) and the intracerebral pathogenicity (ICPI) of our isolate showed medium virulence. Phylogenetic analysis based on F gene sequence showed that the isolate belonged to subgenotype VIb, class II, which dominated in China in recent years. Then, we evaluated the infection efficiency of different routes. Pigeons were randomly divided into five groups of six as follows: intracephalic (IC), intranasal (IN), and intraoral (IO) infection routes, cohabitation infection (CO), and negative control (N negative). All pigeons were inoculated with 100 µl·106 EID50 PPMV-1 virus. After infection, pathological lesions, virus shedding, body weight change, survival rate, and tissue tropism were tested to compare the efficiency of the different infected routes. The mortality of groups IC, IN, IO, and CO were 100, 66.7, 50, and 33.3%, respectively. Weight loss in group IC was higher than the other groups, followed by groups IN and IO. The lesions observed in PPMV-1-infected pigeons were severe, especially in the lung and intestine in group IC. Viral shedding was observed from 2 dpi in groups IC and IN, but the shedding rate was higher in group IN than group IC. The longest period was in group CO. Tissue tropism experiment showed that our isolate has a wide range of tissue distribution, and the virus titer in the heart and intestine of group IC and in the brain of group IN was higher. Our data may help us to evaluate the risk of transmission of PPMV-1.

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The experiment was conducted to evaluate the effects of five rubber seed oil (RSO) levels (0, 1%, 2%, 4%, and 6%) on hens laying performance, egg quality, and yolks fatty acid composition and cholesterol contents. Three hundred and sixty 30-week-old Lohmann Brown laying hens were allotted to 5 groups. The results showed that the egg production was increased in 4% RSO group (P < 0.05), but egg quality parameters and the contents of dry matter, lipid, and protein in yolks were not influenced among treatments (P > 0.05). Yolk cholesterol contents were reduced in RSO supplemental groups (P < 0.05). The concentration of total n-3 PUFA in yolks increased gradually while the ratio of n-6/n-3 decreased gradually with increasing dietary RSO levels (P < 0.001). In conclusion, dietary RSO supplementation increased yolk n-3 PUFA levels, improved yolk color, and reduced yolk cholesterol contents without negative influence on laying performance parameters.

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Trichomonas gallinae is a globally distributed protozoan parasite, mainly affect the upper avian digestive tract and can bring huge economic losses to pigeon industry. The objective of the present study was to determine the prevalence and genotypes of T. gallinae in Beijing, China. A total of 569 samples of throat swabs of pigeon were collected from pigeon farms in Shunyi District, Fangshan District, Daxing District and Miyun District of Beijing. The overall prevalence was 28.30%. The significant difference in infection rates was not observed between regions, but was found between age groups. The highest prevalence was nestling pigeons (33.16%), followed by adolescent pigeons (30.05%) and breeding pigeons (20.59%). Moreover, genotype A and B of T. gallinae were identified by sequencing the ITS1/5.8S/ITS2 regions and phylogenetic analysis. To our knowledge, this is the first report to display the prevalence and genotype of T. gallinae from Beijing, China.

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822 fecal samples from cattle in six areas of Beijing were examined with microscopy for Cryptosporidium oocysts and Giardia cysts. The overall infection rates for Cryptosporidium spp. and Giardia duodenalis were 2.55% and 1.09%, respectively. Cryptosporidium was only detected in calves and heifers, whereas G. duodenalis was found in all age groups. Cryptosporidium spp. were characterized with a PCR-restriction fragment length polymorphism analysis and DNA sequence analysis of the small subunit (SSU) rRNA gene. Two Cryptosporidium species were identified: Cryptosporidium parvum (n=12) and Cryptosporidium andersoni (n=9). Six C. parvum isolates were successfully subtyped with the gp60 gene and three subtypes were detected: IIdA19G1 (n=1), IIdA17G1 (n=1), and IIdA15G1 (n=4). Subtype IIdA17G1 is reported for the first time in cattle worldwide. Nine G. duodenalis isolates were analyzed by sequencing the triosephosphate isomerase (tpi) gene, and only G. duodenalis assemblage E was identified. Therefore, the predominance of C. parvum detected in calves was identical to that found in the Xinjiang Uyghur and Ningxia Hui Autonomous Regions, but differed considerably from that in Henan, Heilongjiang, and Shannxi Provinces. In contrast, the predominance of G. duodenalis assemblage E was more or less similar to its predominance in other areas of China or countries. Our findings confirm the unique character of the C. parvum IId subtypes in China. More systematic studies are required to better understand the transmission of Cryptosporidium and G. duodenalis in cattle in China.

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Enterocytozoon bieneusi is a zoonotic pathogen of the phylum Microspora that infects humans as well as a variety of animal species worldwide. While molecular epidemiologic studies have characterized this parasite in various hosts, isolates from many susceptible hosts have not yet been examined. In this study, E. bieneusi was isolated from 47 Pere David's deer (Elaphurus davidianus) in Henan, China and characterized via PCR analysis of the internal transcribed spacer (ITS) gene. E. bieneusi was detected in 16 out of 47 (34.0%) fecal specimens examined. Sequence analysis of the ITS revealed six known genotypes: type IV (4), EbpC (4), EbpA (4), BEB6 (2), COS-I (1), and COS-II (1). Of these, type IV, EbpC, and EbpA are known to cause human microsporidiosis worldwide, whereas the remaining genotypes are generally specific to ruminants. The present study indicated that Pere David's deer are naturally infected with E. bieneusi, predominantly with zoonotic genotypes, and may pose a risk for human transmission.

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