Effects of Subchronic Copper Poisoning on Cecal Histology and Its Microflora in Chickens

Abstract

Copper (Cu) is an important trace element with a two-sided effect on the growth performance of animals, which depends on the timing and dosage of Cu addition, etc. The purpose of this study was to determine the effects of oral copper sulfate (CuSO4, 350 ppm) on growth performance, cecal morphology, and its microflora of chickens (n = 60) after 30, 60, and 90 days. The results showed that after 90 days of copper exposure, the chickens lost weight, the cecum mucosa was detached, and vacuolation and inflammatory infiltration occurred at the base of the lamina propria. In addition, using the 16S rDNA sequencing method, we observed that copper exposure changed the richness and diversity of intestinal microorganisms. At the phylum level, Proteobacteria and Actinobacteria both significantly increased, while Bacteroidetes significantly decreased in the Cu group compared with control check (CK) group. At the genus level, the relative abundance of Rikenellaceae_RC9_gut_group decreased significantly, while Ruminococcaceae_UCG-014, Lachnoclostridium, and [Eubacterium]_coprostanoligenes_group increased significantly after copper exposure, and the change in microflora was most significant at 90 days. Moreover, the relevance of genus-level bacteria was altered. PICRUST analysis revealed potential metabolic changes associated with copper exposure, such as Staphylococcus aureus infection and metabolic disorders of nutrients. To sum up, these data show that subchronic copper exposure not only affects the growth and development of chickens but also causes the imbalance of intestinal microflora, which may further induce metabolic disorders in chickens.

Gut Microbiota and Serum Metabolite Potential Interactions in Growing Layer Hens Exposed to High-Ambient Temperature

“…Our results show that the influence of heat stress was not manifested as changed alpha diversity of gut microbiome, but changed beta diversity in a time-dependent manner, showing that CHE could alter the structure and composition of cecal microbiota in hens ( 69 ). Going a step further, our result showed the two main dominant phyla altogether comprise above 80% of all the bacterial sequences at the end of the experiment, which agrees with previous studies of gut microbial profiles in birds ( 70 , 71 ). The balance of Firmicutes and Bacteroidetes is measured as a ratio, Firmicutes / Bacteroidetes (F/B), which is a predictive marker reflecting gut microbiota dysbiosis ( 72 , 73 ).…”

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“…Our results show that the influence of heat stress was not manifested as changed alpha diversity of gut microbiome, but changed beta diversity in a timedependent manner, showing that CHE could alter the structure and composition of cecal microbiota in hens (69). Going a step further, our result showed the two main dominant phyla altogether comprise above 80% of all the bacterial sequences at the end of the experiment, which agrees with previous studies of gut microbial profiles in birds (70,71). The balance of Firmicutes and Bacteroidetes is measured as a ratio, Firmicutes/Bacteroidetes (F/B), which is a predictive marker reflecting gut microbiota dysbiosis (72,73).…”

An Overview of Copper Toxicity and Public Health Concerns with Mitigation Strategies

“…Supplementation of Cu in excess amount reduced the feed intake, growth and feed conversion ratio in birds (Hashem et al 2021). Numerous studies have verified the harmful effects of copper on birds (Yigit et al 2012;Hefnawy and El-khaiat 2015;Huang et al 2021). Moreover, by adding 325 ppm in poultry feed leads to initiate the muscle atrophy and growth retardation (Cinar et al 2014).…”