RESUMEN
BACKGROUND: The aim of the current study was to assess the prevalence of bovine tuberculosis (BTB) in cattle, goats, and camels, and its zoonotic potential within the traditional livestock raising communities in four regions of Eritrea. The Single Intradermal Comparative Tuberculin Test (SICTT) as indicator of M. bovis infection was conducted on 1077 cattle, 876 goats, and 195 camels. To elucidate possible risk factors for BTB transmission between animals and its potential zoonotic implication, questionnaire based face-to-face interviews were conducted in households of which 232 raised cattle, 128 goats, and 29 camels. RESULTS: The results of the SCITT were interpreted using the OIE standard (> 4 mm cut-off) for positive responses. In cattle, individual animal (n = 1077) and herd (n = 413) prevalences were 1.2% (n = 13) [Confidence Interval (CI) 95% CI, 1.0-1.3%] and 3.2% (n = 13) (95% CI, 3.0-3.4%), respectively. In goats (n = 876), none of the animals was positive. In camels, individual animal (n = 195) and herd (n = 70), BTB prevalences were 1.5% (n = 3) (95% CI,1.4-1.6%) and 2.9(n = 2) (95% CI, 0.9-4.6%), respectively. Overall, male animals were more at risk (OR = 2.6; 95% CI:1.0-8.7) when compared to females. Sharing of water points, introduction of new animals into herds and migration of animals over large distances were common events that may contribute to intra and inter-species transmission of BTB. Consumption of raw milk, lack of BTB transmission awareness, and low levels of education were common in the farming communities. CONCLUSION: The current study highlighted a low prevalence of M. bovis in cattle, goats and camels in extensive traditional livestock in Eritrea. Despite this, the spatial distribution of affected animals across most of the sampled regions and consumption of unpasteurized milk warrants surveillance, cautious and timely control measures for the disease.
Asunto(s)
Camelus/microbiología , Enfermedades de las Cabras/epidemiología , Tuberculosis Bovina/epidemiología , Crianza de Animales Domésticos , Animales , Bovinos , Eritrea/epidemiología , Femenino , Enfermedades de las Cabras/microbiología , Cabras , Ganado/microbiología , Masculino , Prevalencia , Encuestas y Cuestionarios , Prueba de Tuberculina/veterinariaRESUMEN
Scale and intensive development of mixed crop-livestock agriculture is inevitable in North China Plain (NCP), and nitrogen (N) is one of the key elements that linked the crop and livestock production. Here, we used Hebei Jinlong Circular Agriculture Farm as an example, to analyze the N flow and use efficiency, by using data from literature, on-farm survey and modeling. Further, several on-farm N management improvement practices were proposed and evaluated through scenario analysis, to supply technical support and scientific basis not only for achieving higher N use efficiency and productivity at the farm level, but also providing a new model of circular agriculture in NCP. Our results indicated that manure and purchased fertilizer were the main N input in crop production, which amounted to 674.6 kg N·hm-2·a-1 and accounted for 88.3% of the total N input. Of all the N input in crop production system, only 41.5% ended up in the crop products and around 190.7 kg N·hm-2·a-1 surplus. The excess input of synthetic fertilizer was the main reason for low N use efficiency and high N surplus for crop system. Purchased feed was the main N input pathway in livestock production system, and accounted for 83.2% of the total N input. The annual N excretion rate was 776.6 t N, and around 36.3% of the excreted N was recycled to the crop system. The N use efficiency was 19.7% for livestock production system. The N use efficiency was 40.7% at the whole farm level. The scenarios analysis showed that reducing purchased fertilizer N input by 50% (scenario 1) and increasing the total maize production via adjustment of cropping structure (scenario 2) would increase the N use efficiency in cropping system by 18.7% and 9.8%, respectively. The whole farm use efficiency could be increased by 19.1% through optimizing the feed compositions and regimes (scenario 3). Therefore, reducing purchased fertilizer N input, adjustment of cropping structure and optimizing the feed compositions could increase the N production capacity and achieve an environmental friendly mixed crop-livestock production system simultaneously in NCP.