Short communication: Effects of a commercial triple-strain Bacillus-based probiotic on cecal colonization with Salmonella Enteritidis in commercial layer pullets.

A commercial triple-strain Bacillus-based probiotic was tested to determine its effect on the colonization of the ceca by Salmonella Enteritidis (SE) in commercial layer pullets. Two treatments were tested, each with containing 128 day-of-hatch LSL layer chicks. On top of a standard diet: 1) no supplement (Control, CON), and 2) Probiotic (GalliPro® Fit, 500 g/MT, 1.6 × 106 CFU/g of finished feed, PRO). Environmental swabs were collected from each treatment group and tested to ensure freedom from SE prior to challenge. At 21 days of age, the SE challenge strain was administered orally at a dose of 3.3 × 108 CFU/bird. Pullets from each treatment group (n=32) were euthanized at 6-, 10-, 14-, and 18-days post infection (dpi). Contents from the ceca were aseptically collected and assessed for presence and abundance of SE. No differences in the prevalence of SE positive ceca following oral inoculation (P>0.05) were observed between treatment groups at 6-, 10-, 14-, or 18-dpi. Counts of SE in the ceca of the PRO group were not significantly different (P>0.05) from those of CON at 6- or 10-dpi. However, significantly lower counts of SE in the ceca of the PRO group were observed at 14-dpi (P<0.05) and 18-dpi (P<0.05) compared with CON. SE counts were 1.24 and 1.34 logs lower than CON at 14- and 18-dpi, respectively. In conclusion, supplementation of the triple-strain Bacillus-based probiotic resulted in lower cecal counts of SE compared to those that did not receive an effective probiotic, thereby reducing the risk of foodborne pathogens prior to harvest through sustainable, natural methods.

Effects of a mannan-rich yeast cell wall-derived preparation on cecal concentrations and tissue prevalence of Salmonella Enteritidis in layer chickens.

Salmonella Enteritidis (SE) has been the most common Salmonella serotype associated with foodborne infections in the last several years. Dietary applications of yeast-based preparations in feed have shown to reduce Salmonella colonization in chickens augmenting SE control strategies. This study was conducted to evaluate the effects of a mannan-rich yeast cell wall-derived preparation (Actigen®) administered in feed at a rate of 400 g/ton on SE colonization in the cecum and internal organs of commercial layer chickens. Sixteen week-old layer pullets were orally challenged with a selected nalidixic acid resistant SE strain at a dose of 1.7×10^9 colony forming units (CFU) per bird. SE colonization was assessed by evaluating isolation rates from ovary and pooled liver/spleen samples as well as enumeration of SE in cecal pouches one week post-challenge. Recovery rates of SE from the ovaries of directly challenged birds receiving Actigen® were significantly lower (P <0.02) than those in directly challenged birds fed an unsupplemented control diet. Recovery rates of SE from pooled liver/spleen samples were not significantly different between Actigen®-treated pullets and controls (P = 0.22). Using direct plate count methods, cecal SE concentrations were 1 log10 lower (P <0.001) in challenged pullets in the Actigen®-supplemented group than in the challenged controls. The SE concentration distributions in the ceca were similar in groups testing positive and groups testing negative for SE in the ovaries and liver/spleens tissues. As a result, SE concentrations in the ceca could not be directly related to the occurrence or prevalence of SE in these tissues. In conclusion, Actigen® supplementation appears to decrease the prevalence of SE in ovarian tissue and concentrations of SE in cecal contents and may be useful as a tool for reducing the risk of eggshell contamination and transovarian transmission of SE in eggs.

What evidence do economic evaluations in dental care provide? A scoping review.

OBJECTIVE: To collate the body of evidence in economic studies of different dental interventions. METHODS: Eligible English studies after 1980 were sourced from MEDLINE using MeSH terms and reviewed independently by 4 teams. Studies were grouped according to the type of dental intervention and their quality appraised using Drummond's Checklist. RESULTS: The number of dental economic studies increased from 1980 to 2016. A total of 91 studies were identified following the search strategy. Most studies were conducted in the United States (n=23), followed by Germany (n=14), Australia (n=10) and the United Kingdom (n=9). Preventative dental interventions comprised 37% of included studies (n=34), followed by restorative (n=14), prosthodontic (n=13) and periodontal interventions (n=12). Cost effectiveness analyses (n=68) comprise 75% of full economic evaluation (EE) studies, followed by cost-utility (n=17) and cost-benefit (n=6). Quality assessment checklists identified 60 studies as good, 23 as moderate and 8 as poor. Common methodological limitations were identified in EE studies. Comparison of studies identified trends and common findings within each dental intervention. CONCLUSION: High quality economic studies are important in directing resources and funding by policy makers. Standardisation of reporting outcome measures will improve the potential for interpretation and comparison between studies. Research adhering to recommended quality assessment checklists will improve the overall quality of evidence to better identify cost-effective treatments for different dental interventions.

Effects of feed-borne Fusarium mycotoxins on performance, serum chemistry, and intestinal histology of New Zealand White fryer rabbits.

The objective of the present study was to determine the effects of feeding diets containing grains naturally contaminated with Fusarium mycotoxins to fryer rabbits. The efficacy of a glucomannan mycotoxin adsorbent (GMA) was also examined. Thirty 5-wk-old male New Zealand White rabbits were fed a control diet, a contaminated diet, or a contaminated diet + 0.2% GMA for 21 d. Experimental diets contained deoxynivalenol (DON; vomitoxin) at a concentration of 0.25, 4.3, and 4.9 µg/g, respectively. Feed intake was measured daily and water intake was measured every 3 d. At the end of the feeding period, blood was collected for evaluation of serum chemistry and hematology. Visceral organs were excised, weighed, and processed for histopathological examination. Body weight gain and water intake were greater in rabbits fed the contaminated diet (P = 0.075 and 0.020, respectively) and those fed the contaminated + GMA diet (P = 0.026 and 0.002, respectively) compared with controls. Rabbits fed the contaminated + GMA diet had significantly increased serum urea concentrations (P = 0.023) and decreased serum alkaline phosphatase activity (P = 0.020) compared with controls. Increase in BW gain of rabbits fed the contaminated diets was caused by increased water consumption. There was no effect (P > 0.05) of diet on relative organ weights, but decreased infiltrations with eosinophilic granulocytes were observed in different regions of the intestine in rabbits fed the contaminated or the contaminated + GMA diet. It was concluded that rabbits could be adversely affected by feed-borne Fusarium mycotoxins but appear to be less sensitive than other mammalian species. Supplementation with GMA did not reduce many of the effects of feed-borne mycotoxins.

Effects of dietary Fusarium mycotoxins on intestinal lymphocyte subset populations, cell proliferation and histological changes in avian lymphoid organs.

An experiment was conducted to investigate the effects of dietary Fusarium mycotoxins on gut immunity, cell proliferation, and histology of avian lymphoid organs. The efficacy of a polymeric glucomannan mycotoxin adsorbent (GMA) was also determined. Seventy-two one-day-old male turkey poults were fed corn, wheat, and soybean meal-based diets for 21 days. Diets included control grains, contaminated grains and contaminated grains +0.2% GMA. The major contaminant was deoxynivalenol (3.9 µg/g) with lesser amounts of zearalenone (0.67-0.75 µg/g), 15-acetyl-deoxynivalenol (0.34 µg/g) and HT-2 toxin (0.078-0.085 µg/g). T- and B-lymphocyte populations and crypt cellular proliferation in duodenum, jejunum, ileum and cecal tonsil were measured immunohistochemically on day 14 and 21. Histological changes were recorded after 14 and 21 days of feeding. Feeding contaminated grains significantly increased the percentage of B-lymphocytes in ileum on day 14, and reduced (P<0.05) the percentages of CD8(+)-lymphocytes in cecal tonsil on day 21. GMA supplementation prevented these effects. The feeding of contaminated diets also caused a reduction (P<0.05) in ileal crypt proliferating cells and a significant increase in spleen secondary follicle on day 21. It was concluded that the feeding of grains naturally contaminated with Fusarium mycotoxins results in adverse effects on gut immunity and mucosal cell proliferation.

Morphologic changes in the intestine of broiler breeder pullets fed diets naturally contaminated with Fusarium mycotoxins with or without coccidial challenge.

The effects of feeding diets containing grains naturally contaminated with Fusarium mycotoxins on intestinal histology were studied in chickens raised to 10 wk of age in the absence or presence of coccidial challenge. Experimental diets included the following: controls, diets containing grains naturally contaminated with Fusarium mycotoxins, and diets containing contaminated grains + 0.2% polymeric glucomannan mycotoxin adsorbent. Contaminated diets contained up to 3.8 microg/g deoxynivalenol (DON), 0.3 microg/g 15-acetyl DON, and 0.2 microg/g zearalenone. An optimized mixture (inducing lesions without mortality) of Eimeria acervulina, Eimeria maxima, and Eimeria tenella was used to challenge birds at 8 wk of age. Intestinal tissues were collected from duodenum, jejunum, and ileum prior to challenge; at the end of the challenge period (7 days postinfection; PI); and at the end of the recovery period (14 days PI). Mean villus height (VH) in the duodenum of birds fed the contaminated diets in the absence of coccidial challenge was significantly lower than that of the controls. Mean VH in the jejunum and ileum of the same birds was significantly higher compared to controls, indicating a compensatory mechanism. Fusarium mycotoxins retarded duodenal recovery from coccidial lesions, as indicated by lower duodenal VH and apparent villus surface area comparing challenged birds fed the contaminated diets to challenged controls of the same age. Increased VH was frequently associated with cryptal hyperplasia and increased numbers of mitotic figures in crypts. It was concluded that diets contaminated with Fusarium mycotoxins below levels that negatively affect performance could alter intestinal morphology and interfere with intestinal recovery from an enteric coccidial infection.

Intracranial hemorrhage after use of tissue plasminogen activator for coronary thrombolysis.

Tissue plasminogen activator (tPA), an approved coronary thrombolytic agent, can cause serious bleeding. We report the cases of six patients with intracranial hemorrhage after tPA treatment for acute myocardial infarction. None of the patients were hypertensive at admission, and only one was hypertensive during therapy. Intravenous tPA, 100 mg, was followed by continuous intravenous heparin infusion; intracranial hemorrhage occurred between 2 and 14 hours after tPA infusion ended and between 3 and 17 hours after heparin therapy was started. The partial thromboplastin time (PTT) was excessively prolonged (from 81 s to more than 150 s) in all patients at onset of intracranial hemorrhage. The intracerebral hematomas were predominantly of lobar location, and two patients had multiple simultaneous hemorrhages. Four patients died from massive intracranial hemorrhage; the mechanism for these hemorrhages was unclear. Factors possibly related to hemorrhage include a systemic fibrinolytic state or a platelet anti-aggregant effect produced by tPA and enhanced hemorrhagic tendency caused by the combined effects of tPA and heparin. Local vascular changes at the bleeding site remain as potential contributing factors for isolated intracranial hemorrhage.

Intracerebral hemorrhage and phenylpropanolamine use.

Two patients developed intracerebral hemorrhage within hours from first-time ingestion of phenylpropanolamine-containing medications. One patient had marked hypertension, presented with three intracerebral hematomas, and developed a fourth hemorrhage 10 days later. Angiogram in one patient revealed "beading" of intracranial arteries, an abnormality also detected in a third patient who developed severe headache, vomiting, and acute hypertension following a single dose of phenylpropanolamine. These cases and others reported in the literature strongly suggest an association between phenylpropanolamine ingestion and hemorrhagic stroke. Direct questioning of use of this medication in cases of unexplained intracranial hemorrhage in previously healthy young individuals may reveal an unsuspected high frequency of this association.

Translatability of rat kidney mRNA after mercury administration.

Young male rats received an intraperitoneal injection of 0.5 mg HgCl2/kg body weight and 16 h later the kidneys were removed and homogenized to prepare the polysomal fraction from which the poly(A)+ RNA was obtained. The activity of this fraction was assessed by translating the poly(A)+ RNA in a mRNA-dependent rabbit reticulocyte lysate and the activity was markedly elevated relative to preparations from control rat kidneys. The incorporation of labelled leucine and cysteine, but not phenylalanine, into a low molecular weight protein (approximately 10 000 as judged by denaturing polyacrylamide gel electrophoresis) accounted for the increased mRNA activity. The mobility during electrophoresis of the denatured labelled product and carboxymethylated product, as well as their acidic isoelectric points, provided evidence that it is metallothionein mRNA which exhibits increased translatability in preparations derived from mercury-treated rats.

Does lead exposure influence liver protein synthesis in rats?

The liver and serum of rats was studied 18 hr following the i.p. administration of 0.5 mg Pb2+/100 g body wt. The incorporation of [14C]leucine into proteins was measured in ribosomal and mRNA fractions incubated in vitro and was markedly stimulated in the Pb2+ treated rats. Similar results were found when the proteins of liver and serum were labelled by the injection in vivo of [14C]leucine. The increased mRNA activity appears to be chiefly for acid serum proteins of approx. Mr 44,000, 41,000, 33,000 and 18,000.

Protein synthesis in rat brain following neonatal exposure to lead.

(1) Suckling rats were exposed to lead through the milk of their dams who received a diet of 4% lead carbonate and weanling rats were exposed to 2 injections of 5.0 mg Pb2+/100 g body weight. The brains were used to prepare the following homogenate fractions: postmitochondrial supernatant, postmicrosomal supernatant, ribosomes, initiation factors. (2) The postmitochondrial supernatant fractions were tested in vitro for protein synthesizing activity using the incorporation of labelled phenylalanine, and phenylalanyl-tRNA into peptide. The preparations from the lead-exposed rats had a significant reduction in activity. (3) Peptide formation with the brain ribosomes was not changed in the lead-exposed rats. (4) The aminoacyl-tRNA synthetase reaction was significantly reduced and accounted for most of the reduced peptide formation with brain homogenates from lead-exposed rats. (5) The binding of methionyl-tRNAfMet to ribosomes was increased using initiation factor preparations from the brain of lead-exposed rats.