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Abstract Background Little is known on significance, diversity and characteristics of gut E. coli in goats despite their importance as food animals globally. We characterized the temporal dynamics in diversity of E. coli in fecal samples from a cohort of goat kids and adult meat goats on pasture over a one-year period. Isolates were characterized based on phylogenetic grouping, virulence genes; shiga toxins 1 and 2 (Stx1&Stx2) (STEC), intimin (eaeA), hemolysin (hly) and select important sero-groups (026, 045, 0103, 0126 and 0146) using molecular methods. Results A total of 516 E. coli isolates were screened. Prevalence of virulence genes and STEC was 65 and 56% respectively. Prevalence of virulence genes and STEC was significantly higher in goat kids less than six months (76% /66%) than adults (48% /28%). Isolates with virulence profiles of two or more genes were also higher in young goat kids (50%) than adults (20%). Entero-pathogenic E. coli (EPEC-eaeA gene only) were mostly from pre-weaned goat kids while hly gene only isolates were significantly higher in adults. The stx1, stx2 and hly genes peaked around weaning (60, 63 and 52%) respectively. Goats kids were mostly hosts to group D (59%) while adults older than one year had B1 (75%) isolates. Group D isolates were most abundant at weaning (64%) and diarrhea samples (74%). Group B2 isolates overall (6%) were mostly detected around weaning (63%) while A isolates were 4% overall. Twenty-four isolates belonged to sero-groups 026, 0103 and 0146 with 70% of the isolates detected around weaning. Nineteen of these isolates were STEC with most harboring the stx1/stx2/hly/eae (25%) profile. Most belonged to O26 sero-group (75%) and phylogroup D (75%). Conclusion To our knowledge this is the first study to highlight longitudinal age related differences in E. coli phylogenetic diversity, abundance of virulence genes and select important sero-groups in goats. Differences detected suggest a possible role of age and weaning stress in influencing E. coli diversity in the gut of goats. The findings are relevant to both animal and public health to advise on further studies on caprine E. coli isolates as animal and human pathogens.

This report contains a partial summary of a literature review dealing with the effect of noise on wildlife emphasizing the effects on birds. Beginning with studies in the Netherlands and, later, in the United States, a series of studies have indicated that road noise has a negative effect on bird populations (particularly during breeding) in a variety of species. These effects can be significant with ‘effect distances’ (i.e., those within which the density of birds is reduced) of two to three thousand meters from the road. In these reports, the effect distances increase with the density of traffic on the road being greatest near large, multilane highways with high densities. A similar effect has been reported for both grassland and woodland species. It is important to note that 1) not all species have shown this effect and 2) some species show the opposite response, increasing in numbers near roads or utilizing rights-of-way. It is important to determine the cause of this effect and to utilize additional or alternative methods beyond population densities as the sole measure of effect distance, because the latter is susceptible to variation due to changes in overall population density. Recommendations for further study are given, including alternative measures of disturbance in birds.

There is a scarcity of information on antibiotic resistance in goats. To understand shedding of resistant Escherichia coli in pastured goats, we collected fecal samples from a mixed age cohort over a one-year period. No antibiotic had been used on the study animals one year prior to and during the study period. Resistant isolates were detected in all age groups and prevalence in goat kids was significantly higher than adults; 43−48% vs. 8−25% respectively. The proportion of resistant isolates was higher when animals were congregated near handling facility than on pasture. Most isolates were resistant to tetracycline (51%) and streptomycin (30%), but also to antibiotics that had never been used on the farm; ampicillin (19%). TetB, bla-TEM, (aadA and strpA/strpB) genes were detected in 70%, 43%, (44% and 24%) of tetracycline, ampicillin, and streptomycin resistant isolates respectively. Resistant isolates also harbored virulent genes and some belonged to D and B2 phylogenetic groups. Thus, pastured goats, despite minimal exposure to antibiotics, are reservoirs of resistant E. coli that may contaminate the environment and food chain and spread resistant genes to pathogenic bacteria and some that are potential animal and human pathogens. Environmental sources may play a role in acquisition of resistant bacteria in pastured goats.

Cancers of the lymphatic system are broadly classified into Hodgkin and non-Hodgkin types. Although lymphomas can be effectively treated with chemotherapy, this approach is associated with the risk of adverse side effects. High intake of certain vegetables and fruits is associated with a reduced risk of cancer development. We hypothesized that Annona fruit, which is rich in fibers and phytochemicals that are known to possess anticancer properties, can be effective in inhibiting lymphoma growth. The Annona fruit's fractions were extracted with water, methanol, or chloroform and then assayed for total phenolic, flavonoids, and tannins content; antioxidation activities; and inhibition of in vitro cell proliferation using the Ramos-1 lymphoma cells. The methanol fractions contained the highest phenolics, flavonoids, and tannins content, and antioxidation activity. However, the methanol extracts of skin, pulp, and seeds had a moderate whereas the chloroform extracts of pulp and seeds had strong effects on Ramos-1 cell proliferation. Our findings suggest that Annona fruits may be effective in the prevention or treatment of lymphoma., Competing Interests: All authors declare no conflict of interest., (© 2019 The Authors. Food Science & Nutrition published by Wiley Periodicals, Inc.)

Accurate prediction of the thermal destruction rate of foodborne pathogens is important for food processors to ensure proper food safety. When bacteria are subjected to thermal stress during storage, sublethal stresses and/or thermal acclimation may lead to differences in their subsequent tolerance to thermal treatment. The aim of the current study was to evaluate the thermal tolerance of Escherichia coli O157:H7, Listeria monocytogenes , Salmonella enterica , and Staphylococcus aureus that are incubated during overnight growth in tryptic soy broth at four temperatures (15, 25, 35, and 45°C). Following incubation, the bacteria were subjected to thermal treatments at 55, 60, and 65°C. At the end of each treatment time, bacterial survival was quantified and further calculated for the thermal death decimal reduction time ( D- value) and thermal destruction temperature ( z- value) using a linear model for thermal treatment time (min) vs. microbial population (Log CFU/ml) and thermal treatment temperature (°C) vs. D- value, respectively, for each bacterium. Among the four bacterial species, E. coli generally had longer D- values and lower z- values than did other bacteria. Increasing patterns of D- and z- values in Listeria were obtained with the increment of incubation temperatures from 15 to 45°C. The z- values of Staphylococcus (6.19°C), Salmonella (6.73°C), Listeria (7.10°C), and Listeria (7.26°C) were the highest at 15, 25, 35, and 45°C, respectively. Although further research is needed to validate the findings on food matrix, findings in this study clearly affirm that adaptation of bacteria to certain stresses may reduce the effectiveness of preservation hurdles applied during later stages of food processing and storage., Competing Interests: The authors declare no conflict of interests., (© 2019 The Authors. Food Science & Nutrition published by Wiley Periodicals, Inc.)

There is a scarcity of information on antibiotic resistance in goats. To understand shedding of resistant Escherichia coli in pastured goats, we collected fecal samples from a mixed age cohort over a one-year period. No antibiotic had been used on the study animals one year prior to and during the study period. Resistant isolates were detected in all age groups and prevalence in goat kids was significantly higher than adults; 43-48% vs 8-25% respectively. The proportion of resistant isolates was higher when animals were congregated near handling facility than on pasture. Most isolates were resistant to tetracycline (51%) and streptomycin (30%), but also to antibiotics that had never been used on the farm; ampicillin (19%). TetB , bla - TEM , ( aadA and strpA / strpB ) genes were detected in 70%, 43%, (44% and 24%) of tetracycline, ampicillin, and streptomycin resistant isolates respectively. Resistant isolates also harbored virulent genes and some belonged to D and B2 phylogenetic groups. Thus, pastured goats, despite minimal exposure to antibiotics, are reservoirs of resistant E. coli that may contaminate the environment and food chain and spread resistant genes to pathogenic bacteria and some that are potential animal and human pathogens. Environmental sources may play a role in acquisition of resistant bacteria in pastured goats.

Improper food processing is one of the major causes of foodborne illness. Accurate prediction of the thermal destruction rate of foodborne pathogens is therefore vital to ensure proper processing and food safety. When bacteria are subjected to pH and thermal stresses during growth, sublethal stresses can occur that may lead to differences in their subsequent tolerance to thermal treatment. As a preliminary study to test this concept, the current study evaluated the effect of prior pH and thermal stresses on thermal tolerance of Salmonella and Staphylococcus using a tryptic soy broth supplemented with yeast extract. Bacteria incubated at three pH values (6.0, 7.4, and 9.0) and four temperatures (15, 25, 35, and 45°C) for 24 hr were subjected to thermal treatments at 55, 60, and 65°C. At the end of each treatment time, bacterial suspensions were surface-plated on standard method agar for quantification of bacterial survival and further calculation of the thermal death decimal reduction time ( D -value) and thermal destruction temperature ( z -value). The effect of pH stress alone during the incubation on the thermal tolerance of both bacteria was generally insignificant. An increasing pattern of D -value was observed with the increment of thermal stress (incubation temperature). The bacteria incubated at 35°C required the highest z -value to reduce the 90% in D -values . Staphylococcus mostly displayed higher tolerance to thermal treatment than Salmonella . Although further research is needed to validate the current findings on food matrices, findings in this study clearly affirm that adaptation of bacteria to certain stresses may reduce the effectiveness of preservation procedures applied during later stage of food processing and storage., Competing Interests: The authors declare no conflict of interests.

Surgical implantation of tissues into the brain causes trauma to the region receiving the graft. This study shows that real or simulated striatal trauma in hemiparkinsonian rats leads to increased expression of two trophic factor mRNAs: ciliary neurotrophic factor (CNTF) and brain-derived neurotrophic factor (BDNF). The baseline expression of BDNF mRNA was also markedly lower in dopamine-depleted striatum than in normal striatum in non-traumatized (control) hemiparkinsonian rats. Striatal CNTF message was relatively symmetrical in the non-traumatized (control) hemiparkinsonian rats. Host production of these and other trophic factors may play important roles in the response to tissue grafting, to enhance graft survival and as a stimulus to regenerative collateral axonal sprouting.

We have previously reported that ciliary neurotrophic factor (CNTF) mRNA is upregulated in the rat striatum following trauma and that its peak is coincident with a peak in the number of GFAP-positive astrocytes. CNTF, or other neurotrophic factors present in the traumatized striatum, may be involved in the dopaminergic fiber sprouting seen following cavitation or graft implantation in animal models of Parkinson's disease. This study was undertaken in order to further characterize the neurotrophic activity present following trauma through the use of bioassays. Adult rats underwent stereotaxic biopsy of the right striatum, and gelatin sponge [gelfoam (GF)] was placed in the resultant cavity. GF was collected from 1 to 30 days following trauma and homogenized. GF extracts (with equal protein concentrations) were assayed using dorsal root ganglion (DRG) explants, dissociated ciliary ganglia (CG), and human dopaminergic neuroblastoma cell (SH-SY5Y) cultures. The GF extracts had significant neurite-promoting activity (NPA) for DRG, CG, and SH-SY5Y cells, with the maximum effect seen 7 days after trauma. NPA was not blocked by anti-nerve growth factor (NGF) Ab, but anti-brain-derived neurotrophic factor (BDNF) Ab significantly blocked the activity for DRG. The GF extracts protected the SH-SY5Y cells from the neurotoxins 6-OHDA and MPP+, as did NGF and BDNF. This neuroprotective effect of GF was not blocked by anti-NGF Ab. This study suggests that the neurotrophic activity in GF extracts has CNTF-like and BDNF-like components as well as another, undefined component.

Transplantation of dopaminergic or neurotrophic tissues is an experimental treatment of Parkinson's Disease. However, in animal models sustained recovery may occur after surgical trauma to affected brain areas even in the absence of grafted tissue. Consequently, brain tissue reacting to local trauma in these experiments must be capable of substantial neurotrophic responses. To evaluate the potential of astrocytes in these neurotrophic responses, cultures were obtained from gelatin implants into striatal cavities that were created in hemiparkinsonian rats. The type 1 astrocyte phenotype as determined immunocytochemically was maximal at day 7 in vitro and paralleled the glial reaction in the adjacent brain parenchyma. Neurite-promoting activity of the culture medium was determined in a chick dorsal root ganglion bioassay and also was established by 7 days. Nerve growth factor antibodies neutralized only around 40% of this activity. Neurotrophic activity was absent with assay of media from early or long-term newborn rat astrocytes, and of medium conditioned by a monoyte/macrophage cell line. Passage after several months yielded astrocyte cultures that repeated a surge of neurite-promoting activity. This long-term potential to produce multiple neurotrophic factors indicates that autologous astrocytes in affected brain regions may serve either as targets for or agents of therapy of Parkinsonism.