Acorn-related acquired pseudomelanosis in Calabrian black pigs

Abstract

Background Melanosis of lymph nodes in black pigs has generally been related to regression of congenital melanoma and, occasionally, to ingestion of acorns. The aim of this manuscript is to confirm the hypothesis of a possible acquired acorn-related pseudomelanosis in the Nero Calabrese pig , a swine breed belonging to the group of Italian native breeds and whose coverage area corresponds to the region of Calabria, southern Italy. This pig is characterized by slow-growing subjects, producing, however, high quality meat suitable for the production of sausages and fine hams. The study was carried out on 142 normally slaughtered pigs. All organs were examined. Lymph nodes and intestine (jejunum) were sampled. Histochemistry was performed on deparaffinized histological sections to identify the cell types involved and to characterize the pigment stored. To further confirm the pigmentation disorder, immunohistochemistry was carried out. Total phenolic substances were identified in acorns through the use of a biochemical reaction. Results Lymph node pigmentation appears directly related to acorn ingestion, with a higher incidence in the group which was 70% natural fed (acorn of Quercus virgiliana ). Moreover, findings obtained revealed how different amounts of phenolic substrates present in Q. virgiliana and Q. ilex acorns can influence the incidence of such exogenous pigmentation. Conclusion The findings obtained in this study confirm the acquired nature of the melanin-like pigmentation detected in lymph nodes from acorn-fed swine. Acquired pigmentation must be differentiated from true melanosis as well as from melanosis related to tumor regression of congenital melanoma. This thesaurismosis can be proposed as a marker of wellbeing and quality, confirming that the pigs have been bred and fed in natural conditions. Electronic supplementary material The online version of this article (10.1186/s12917-019-1934-5) contains supplementary material, which is available to authorized users.

Prevalence of Bovine Tuberculosis in Slaughtered Cattle in Sicily, Southern Italy

“…Experimental studies demonstrated that macroscopic lesions may be found in cattle 14 days post-infection [ 45 ], but in some instances, 6–8 weeks are required [ 46 ], and, especially in early infection, lesions are invisible to the naked eye. However, despite its low sensitivity and apparently low contribution in bTB surveillance system, post-mortem inspection at the slaughterhouse allows the detection of residual infection cases [ 21 , 24 , 25 , 47 ], also providing essential epidemiological data on zoonotic diseases [ 48 , 49 ] and allowing the documentation of several pathological findings [ 50 , 51 ].…”