Erratum to: Building towards a standardised approach to biocorrosion studies: a review of factors influencing Mg corrosion in vitro pertinent to in vivo corrosion (vol 61, pg 475, 2018)

SUMMARYFactors which could be expected to influence levels of ammonia in the rumen were compared in sheep maintained on diets providing 11·4 or 20·7 g N/day.The ruminal fluid volume in sheep given the lower-N ration was 78% of that in sheep maintained on the higher-N diet. The effect of this in diluting rumen ammonia from recycled urea is discussed.Ruminal urease activity was higher in sheep given the lower-N diet, and was confined to the particulate fraction of rumen liquor in animals given either diet. At least 95% of the maximum activity occurred in the range of pH 5·4–7·05, and pH 6·0–7·25 in sheep maintained on the lower- and higher-N diets respectively. Small variations in activity were observed between the morning and evening meals.In vitro rates of net ammonia production in samples of rumen liquor were similar in sheep given either diet; a positive correlation with the initial ammonia concentration was evident. Net utilization of ammonia was detected in some experiments in samples from sheep maintained on the lower-N diet. Starvation for 1 day was associated with increased rates of production and initial concentrations of ammonia.Cellulose, as cotton thread, was digested at similar rates in vivo in sheep given the different diets. This is discussed in relation to the demand for ammonia by cellulolytic bacteria.

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Factors influencing horizontal gene transfer in the intestine

Animal Health Research Reviews ◽

10.1017/s1466252317000159 ◽

2017 ◽

Vol 18 (2) ◽

pp. 153-159 ◽

Cited By ~ 11

Author(s):

Ximin Zeng ◽

Jun Lin

Keyword(s):

Gene Transfer ◽

Horizontal Gene Transfer ◽

Stress Hormones ◽

Critical Role ◽

Ecological Niches ◽

Melting Pot ◽

Effective Strategies ◽

Factors Influencing

AbstractAntibiotic resistance (AR) is ancient. Use of antibiotics is a selective driving force that enriches AR genes and promotes the emergence of resistant pathogens. It also has been widely accepted that horizontal gene transfer (HGT) occurs everywhere and plays a critical role in the transmission of AR genes among bacteria. However, our understanding of HGT processes primarily build on extensivein vitrostudies; to date, there is still a significant knowledge gap regardingin situHGT events as well as the factors that influence HGT in different ecological niches. This review is focused on the HGT process in the intestinal tract, a ‘melting pot’ for gene exchange. Several factors that potentially influencein vivoHGT efficiency in the intestine are identified and summarized, which include SOS-inducing agents, stress hormones, microbiota and microbiota-derived factors. We highlight recent discoveries demonstrating that certain antibiotics, which are widely used in animal industry, can enhance HGT in the intestine by serving as DNA-damaging, SOS-inducing agents. Despite recent progress, research onin vivoHGT events is still in its infancy. A better understanding of the factors influencing HGT in the intestine is highly warranted for developing effective strategies to mitigate AR in animal production as well as in future agricultural ecosystems.

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