Ticks are blood-feeding arthropods and transmit a variety of medically important viral, bacterial, protozoan pathogens to animals and humans. Ticks also harbor a diverse community of microbes linked ...to their biological processes, such as hematophagy, and hence affect vector competence. The interactions between bacterial and/or protozoan pathogens and the tick microbiome is a black-box, and therefore we tested the hypothesis that the presence of a protozoan or bacterial pathogen will alter the microbial composition within a tick. Hence, this study was designed to define the microbial composition of two tick species, Hyalomma (H.) anatolicum and Rhipicephalus (R.) microplus. We used a combination of PCR based pathogen (Anaplasma marginale and Theileria species) and symbiont (Wolbachia species) identification followed by metagenomic sequencing and comparison of the microbial communities in PCR positive and negative ticks. A total of 1786 operational taxonomic units was identified representing 25 phyla, 50 classes, and 342 genera. The phylum Proteobacteria, Firmicutes, Actinobacteriota, and Bacteroidota were the most represented bacteria group. Alpha and beta diversity were not significantly affected in the presence or absence of Theileria sp. and A. marginale as see with H. anatolicum ticks. Interestingly, bacterial communities were significantly reduced in Theileria sp. infected R. microplus ticks, while also exhibiting a significant reduction in microbial richness and evenness. Putting these observations together, we referred to the effect the presence of Theileria sp. has on R. microplus a “pathogen-induced dysbiosis”. We also identify the presence of Plasmodium falciparum, the causative agent of human malaria from the microbiome of both H. anatolicum and R. microplus ticks. These findings support the presence of a “pathogen-induced dysbiosis” within the tick and further validation experiments are required to investigate how they are important in the vector competence of ticks. Understanding the mechanism of “pathogen-induced dysbiosis” on tick microbial composition may aid the discovery of intervention strategies for the control of emerging tick-borne infections.
Background
Haemonchosis is a fatal disease of small ruminants caused by the parasite
Haemonchus contortus
(
H. contortus
). The most common drugs used in the treatment of
H. contortus
include ...albendazole, oxfendazole, and ivermectin. However, as previously reported in the treatment of haemonchosis, these medicines have acquired drug resistance problems over time. Interestingly, natural plant compounds have demonstrated promising effects in the treatment of
H. contortus
. Therefore, the current study evaluated the effects of plant extract,
Ferula asafetida
, against common drugs such as albendazole, oxfendazole, ivermectin, and closantel for the treatment of haemonchosis in small ruminants.
Methodology
The current study was conducted on different small ruminant farms in Kasur District, Punjab, Pakistan. The positive animals (
n
= 720) after coprological examination were selected in this study and divided into two major groups (
n
= 360 goats and
n
= 360 sheep). Further, animals were divided into five treatment groups (A–E) and one control group with no treatment (F). Albendazole, oxfendazole, ivermectin, closantel, and
Ferula asafetida
were administered orally to groups A–E, respectively. The eggs per gram feces (EPG) were determined through the McMaster technique on days 0, 7th, and 14th of treatment.
Results
The results showed a significantly higher efficacy of closantel and
Ferula asafetida
against
H. contortus
in both goats (100% and 70%;
p
< 0.05) and sheep (99% and 87%;
p
< 0.05), respectively. No correlation was observed between EPG reduction with age and gender in both goats and sheep.
Conclusion
Allopathic drug closantel and herbal drug,
Ferula asafetida
, have been proved an effective dewormer against
H. contortus
in small ruminants
.
Coxiella burnetii
, an intracellular zoonotic bacterium, causes query (Q) fever in ruminants. Its role has never been elucidated in small ruminants from Pakistan. The current study is designed to (a) ...determine the prevalence of coxiellosis in small ruminants, (b) evaluate the association of various potential risk factors and biomarkers in the occurrence of
Coxiella burnetii
, (c) and determine phylogeny and genetic variability of its various isolates identified during the study. For this purpose, 320 blood samples from sheep (
n
= 160) and goats (
n
= 160) were collected from 9 Union Councils of district Kasur, Punjab, and processed for DNA extraction.
C. burnetii
was confirmed by amplification of IS1111 transposase gene with an amplicon size of 294 bp. The results showed that the overall positive percentage of
C. burnetii
is 36.87% (sheep: 46.9% and goats: 30%). The phylogenetic tree was also constructed which described the possible origin of this pathogen from environment. Besides, after translation into amino acid, the resultant alignment showed several unique changes at position numbers 18 and 27 in the isolates from goats and at 27 and 66 from those of sheep. These mutations can have major impact on the infectious characteristics of this pathogen. Furthermore, different potential risk factors and clinical biomarkers like age, tick infestation, abortion, mastitis, and infertility were also studied and found that these are significantly (
p
< 0.05) associated with the occurrence of coxiellosis. It is concluded from the study that
C. burnetii
is endemic in small ruminants in Punjab, Pakistan. The outcomes of this study are alarming for scientific community as well as for policy makers because coxiellosis is an emerging threat to both humans and animals in this region due to its interspecies transmission ability.