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Proventriculus from 4 week old broiler chicken diagnosed with TVP. Photomicrograph showing necrotic debris in dilated glandular lumen (black arrows); replacement of glandular epithelium by hyperplastic ductal epithelium (white arrows); infiltration of lymphoid cells (asterisks). Hematoxylin and eosin.
Source publication
The aim of the study was to investigate the possibility of Transmissible Viral Proventriculitis (TVP) occurrence in broiler chickens in Poland. In march 2016 proventriculi samples were collected from broiler chickens showing poor uniformity and decreased body weight, accompanied by enlarged proventriculi. Histopathological examination of affected p...
Citations
... The glandular part of the stomach (proventriculus) of the birds is functionally equivalent to the mammals' stomach, and development of various pathological processes in its structure clinically manifests in digestion impairments, and this in turn leads to decreased productivity parameters of the birds. The pathohistological changes we observed in the proventriculus of the ill birds are consistent with the studies of foreign authors (Goodwin et al., 1996;Grau-Roma et al., 2010;Śmiałek et al., 2017), who reported the same processes during TVP. The causative agent of TVP is yet to be identified, which complicates the instrumental methods of disease diagnostics, though according to most researchers, the histological methods of the study play the main role in diagnosing TVP. ...
Transmissive viral proventriculitis (TVP) is a new avian disease, the etiology and pathogenesis and diagnostics of which remain unidentified, being therefore a subject of an active ongoing discussion among researchers and veterinary doctors. Cases of the disease have been reported and registered in many countries of the world. On poultry farms of Ukraine, this disease started to be diagnosed in 2019, according to the characteristic pathognomic changes. The article presents the results of pathoanatomical, histological and electronic-microscopical studies of the glandular part of the stomach of 62 ill broiler chickens aged 24-28 days and 7 clinical healthy broiler chickens of the same age. The samples of the proventriculus from the infected and clinically healthy chickens were fixated in 10% aqueous solution of neutral formalin and in 1.5% solution of glutaraldehyde in 0.2 molar cacodylate buffer (рН 7.2). Pathoanatomic necropsy of the infected broiler chickens revealed overall anemia, decrease in the volume of the spleen, thymus and fecal sac. In the glandular part of the stomach, the wall was slightly thickened, non-homogenously stained on the section, the mucous membrane being swollen, covered by dense whitish mucous. According to the histological study, the proventriculus of the broiler chickens had lymphocytic necrotizing proventriculitis. In the tubular-alveolar structures of the mucous membrane, there prevailed alteration of the secretory epithelium, with its transformation into ductal epithelium, combined with lymphocytic infiltration of the interstitium. Intensive necrosis of most glandular (oxynticopeptic) cells was accompanied by their exfoliation from the basal membrane of the secretory parts, with desquamated cells accumulating in enlarged lumens of alveoli and excretory ducts. Further, necrotized oxynticopeptic cells in the tubular-alveolar glands were actively replaced by cylindrical ductal cells, and also their hyperplasia and hypertrophy occurred. Diffusive and multifocal interalveolar round-cell infiltrates were mostly presented by lymphocytes, among which there occurred plasmocytes, macrophages, and heterophils. Ultrastructural studies of secretory cells revealed presence of pathogen virions in nucleus and cytoplasm. Based on the morphological changes in the birds’ proventriculus, we diagnosed transmissive viral proventriculitis, which had not been recorded in Ukraine before.
... It has recently been estimated that body weight gains can decrease in the course of TVP by more than 30% over 14 days post infection (Śmiałek et al. 2020). Since the first description of TVP in 1978, when it was diagnosed in the Netherlands, cases have been identified and described in the USA, Australia, China, South Korea, Spain, France, the UK, and Poland (Kouwenhoven et al. 1978, Goodwin et al. 1996, Yu et al. 2001, Dormitro et al. 2007, Grau-Roma et al. 2010, Marquerie et al. 2011, Hafner and Guy, 2013, Kim et al. 2015, Śmiałek et al. 2017. ...
Transmissible Viral Proventriculitis (TVP) is a disease of chickens which contributes to significant production losses. Recent reports indicate the role of chicken proventricular necrosis virus (CPNV) in the development of TVP. However, the relationship between CPNV and TVP is inconclusive and it has been addressed in just a few reports. Given the above, a study was conducted to identify the relationship between TVP and CPNV prevalence in broiler chickens in Poland. The study was carried out on 35 proventriculi samples sent for histopathological (HP) examination to the Faculty of Veterinary Medicine in Olsztyn between 2017 and 2019. After HP examination, TVP positive samples were processed for CPNV identification by RT-PCR. TVP was the most common pathological condition of proventriculi (23 cases). CPNV was identified in 10 out of those 23 cases. The average HP score, and the average necrosis and infiltration score for CPNV-positive samples was significantly higher than in CPNV-negative ones. The average age of the CPNV-positive chickens was significantly lower than in CPNV-negative birds. Our study confirms the role of CPNV in TVP pathogenesis and it seems that preservation of the proventriculi in the early stages of the disease, when the lesions are more pronounced, should result in a greater probability of CPNV detection.
... The first reports on TVP date back to 1978 and come from the Netherlands [2], when Kouwenhoven et al. reported a case of proventriculitis in commercial chicken broilers and proved that TVP was induced by an infectious factor. Since then, TVP cases have been identified and reported in the USA, Australia, China, South Korea, Spain, France, the UK, and Poland, among other countries [3][4][5][6][7][8][9][10]. ...
... Given the recent cases of TVP recorded in Poland [9], a laboratory-conditions study was undertaken that attempted to reproduce the clinical course of TVP in broiler chickens by inoculating them with a homogenate of proventriculi from a confirmed TVP field case. The research was also aimed at identifying the etiological factor in domestic cases of TVP. ...
... Proventriculi from the first described Polish case of TVP [9] were used for the experimental infection. The proventriculi that were used for the experimental infection in our study were collected from 5-week-old Ross 308 broiler chickens from a commercial farm and they were confirmed by histopathological examination to be TVP-positive. ...
Transmissible viral proventriculitis (TVP) of chickens is manifested in decreased body weight gains, poor feed conversion and weight diversity. Although TVP etiology has not been defined, a Birnaviridae family member, named chicken proventricular necrosis virus (CPNV) is considered as a potential factor of a disease. This study was undertaken in order to reproduce TVP and to evaluate its etiology. Broiler chickens of the TVP-infected group were inoculated with TVP positive proventriculi homogenate on the 24th day of life. Samples were collected, on infection day and 14 days post-infection (dpi). The 14 dpi anatomo- and histopathological evaluation, revealed that we have succeeded to reproduce TVP. TVP-infected birds gained 30.38% less body weight. In the TVP-infected group a seroconversion against picornaviruses, fowl adenoviruses (FAdV) and infectious bursal disease viruses (IBDV) was recorded with an ELISA test. Using RT-PCR and PCR, CPNV was detected in proventriculi and FAdV in spleens and livers of infected birds, 14 dpi. Our study supports that CPNV is involved in the development of TVP. We did not record the presence of IBDV in TVP or control birds, despite our recording of a seroconversion against IBDV in TVP infected birds. CPNV and IBDV belong to the same family, which allows us to assume serological cross-reactivity between them. The role of FAdV needs further evaluation.
... The rst reports on TVP date back to 1978 and come from the Netherlands [2], when Kouwenhoven et al. reported a case of proventriculitis in commercial chicken broilers and proved that TVP was induced by an infectious factor. Since then, TVP cases have been identi ed and reported in the USA, Australia, China, South Korea, Spain, France, the UK, and Poland among other countries [3][4][5][6][7][8][9][10]. ...
... Given the recent cases of TVP recorded in Poland [9], a laboratory-conditions study was undertaken that attempted to reproduce the clinical course of TVP in broiler chickens by inoculating them with a homogenate of proventriculi from a con rmed TVP eld case. The research was also aimed at identifying the etiological factor in domestic cases of TVP. ...
... Proventriculi from the rst Polish case of TVP [9] were used for the experimental infection. After homogenization, proventriculus samples were processed through three freeze-thaw cycles. ...
Background
Transmissible viral proventriculitis (TVP) is an infectious disease reported in all production types of chickens. TVP is manifested in decreased body weight gains, wide weight diversity of birds in the flock and poor feed conversion. Histopathological examination seems to be the most reliable method for confirming the disease. Although TVP etiology has not been explicitly defined, a novel virus identified as a member of the Birnaviridae family, named chicken proventricular necrosis virus (CPNV) has been isolated from clinical cases of TVP and it is now considered as a potential factor of a disease. The study was undertaken in order to reproduce the disease under laboratory conditions and to evaluate the etiology of first described Polish case of TVP.
Results
Anatomopathological and histopathological evaluation reveled that we've succeeded to reproduce TVP in broiler chickens. Within 14 days after infection birds gained approximately 30,38% less body weight in comparison to Control group. In TVP infected group a seroconversion against FAdV and IBDV was recorded 14 days post infection (dpi). 14 dpi CPNV was detected in proventriculi, while FAdV in spleens and livers of infected birds.
Conclusions
We have demonstrated that CPNV was involved in the development of the disease. We did not record the presence of IBDV in the TVP or control birds, despite our recording a strong seroconversion against IBDV in the birds from the TVP group. CPNV belongs to the same family as IBDV, which allows us to assume serological cross-reactivity between them. This possibility of CPNV infections affecting IBDV antibody levels detected by commonly available ELISAs should be taken into account under poultry field conditions and diagnosis. The role of FAdV in the development of TVP needs further evaluation.
Transmissible viral proventriculitis (TVP) is a disease previously described only in broiler chicken of 4 to 5 weeks. Still, recently it has also been known to affect broiler breeder and commercial layer hens of 9–20 weeks. Symptoms include proventricular enlargement, stunted growth, poor feed conversion ratios, and impaired feed digestion. This disease can be diagnosed only by inflammation and enlargement of the proventriculitis and histopathological evidence of the proventriculus glands necrosis. Increasing evidence suggests the possible presence of TVP in broiler chickens in Algeria. In this study, proventriculitis was diagnosed in April 2020 on multiage broiler chickens farm in eastern of Algeria. Clinical signs mostly consisting of impaired growth and reduced uniformity of birds, the postmortem findings were enlarged proventriculi, widening of the gastric isthmus, a thickened wall with dilated gland openings, and white foci on the serosal surface. Histopathological examination of affected proventriculi showed typical lesions of TVP (severe lymphocytic infiltration, replacement of glandular epithelium by hyperplastic ductal epithelium, and glandular necrosis). To our knowledge, this is the first case indicating the presence of TVP in Algeria and North Africa.
We investigated the occurrence and pathologic findings of transmissible viral proventriculitis (TVP) associated with the chicken proventricular necrosis virus (CPNV) in commercial broiler chickens in southeastern Brazil. Seventy-three broilers, 25–36 d old, with a history of reduced growth, were referred to our veterinary pathology services from 2013 to 2017. Broilers were clinically examined, weighed, and euthanized for postmortem examination. Broilers of different ages with proventricular histologic lesions were positive for CPNV by RT-PCR; however, the intensity of histologic lesions was higher among 33-d-old animals, and viral RNA detection was more frequent among those that were 28 d old. In the proventriculi of 35 of 73 (48%) broilers, lesions were characterized by glandular epithelial necrosis, lymphoplasmacytic and histiocytic infiltrates, and metaplasia of glandular epithelium to ductal epithelium. In 24 of 73 (36%) broilers with histologic TVP-compatible lesions, CPNV was detected by RT-PCR for the viral protein 1 ( VP1) gene. Broilers with histologic lesions were lighter than expected compared to the Cobb 500 standard weight. TVP has not been reported previously in broiler chickens in Brazil, to our knowledge.
Transmissible viral proventriculitis (TVP) is a disease of chickens, mostly in broilers of 2–8 wk of age. Chicken proventricular necrosis virus (CPNV), a birnavirus, is the etiologic agent. Characteristic gross lesions are enlargement, atony, and pallor of the proventriculus. Cases diagnosed in California between 2000 and 2018 (n = 477), originating from 93 different farms representing all major companies in the region, were analyzed. Frequency of cases varied widely between years, with no recognizable seasonality. The flocks were between 6 and 61 days of age; the average age was 34.0 days, and the median age was 35 days. In 166 cases, between 6.3% and 100% of the submitted birds had gross lesions in the proventriculus. The most common findings were enlarged or dilated proventriculi, thickened walls, and pale or mottled serosal appearance. Histopathologically, inflammation of the glands was the most frequent finding. Other lesions included necrosis, hyperplasia, or both conditions of the glandular epithelium; dilated glands; and occasionally fibrin deposition, fibrosis, and hemorrhages. Twenty-three proventriculi from six cases were tested by immunohistochemistry for the presence of CPNV antigen; 21 stained positive. In 209 cases, birds also had lesions in the bursa fabricii attributed to infectious bursal disease, but with no significant difference in the mean percentage of birds with gross lesions in the proventriculus between cases with or without lesions in the bursa fabricii. The results show that TVP is a common disease of broiler flocks in California and confirms that CPNV is the likely causative agent.
Flock health monitoring program is an important system, used in the poultry
industry worldwide to minimize the production cost, detect clinical and
subclinical diseases and acquire data to make comparisons among the farms
and identify the future research area. The present study was aimed to
investigate the broiler health status through a flock health monitoring program
using the lesion scoring method. For this purpose, a total of 540 broiler birds
were collected from four different places from January to December 2017 and
necropsied. Five body systems including gastrointestinal, respiratory, immune,
skeletal, and integumentary were monitored with their 33 parameters during
the study period. All the scores obtained from different parameters were
analyzed and summarized. Among the body systems, lesion scores percentages
were more prevalent in the parameters of the gastrointestinal, respiratory, and
immune systems. Regarding age groups, 2nd (0-84.4%) and 3rd weeks (0-
78.3%) had most of lesion scores percentage compared to 4th weeks (0-70.6%).
With respect to season, lesion scores percentages were highest in summer (0-
87.2%) and winter season (0-76.7%) respectively than monsoon season (0-
68.3%). Based on different scores, zero was scored by the most number of
birds ranged from 22.6-100%, while one was scored in 0-66.9%, two in 0-
15.2%, three in 0-5.9%, and four in 0-0.4% of birds, respectively. Flock health
monitoring program is a mirror of flock health status that can be a great
alternative for the poultry industry and manager. Thus, the flock monitoring
program mainly emphasizes poultry health which can be a good approach for
future disease prevention.
