Effect of dietary inclusion of ascorbic acid and palm oil on the performance of laying hens in a hot tropical environment

1. Two experiments were conducted to evaluate the effects of including ascorbic acid (AA), palm oil or a combination of both in the diets of laying hens during the hot months in a tropical environment.

2. The inclusion of AA improved egg production, food intake and efficiency of utilisation, and decreased the cost of food per kg egg. The addition of 400 mg AA/kg diet gave the most efficient performance.

3. Palm oil inclusion reduced the effect of heat stress and increased egg production, egg weight, food intake and efficiency of utilisation.

4. When 200 mg AA and 50 g palm oil/kg were used, additive responses were obtained with further improvements in egg production, food cost and efficiency.

5. Ascorbic acid and palm oil when fed alone or in combination reduced the incidence of cracked eggs.

6. Thus, 400 mg ascorbic acid/kg of diet, 50 g palm oil or 200 mg AA plus 50 g palm oil/kg diet ameliorated the effects of heat stress in laying hens.     

Clinical,pathologic, and toxicologic characterization of Salvia reflexa (lance-leaf sage) poisoning in cattle fed contaminated hay

Salvia reflexa (lance-leaf sage)-contaminated alfalfa hay was fed to ~500 mixed-breed beef cattle. Within hours of exposure, nearly half of the cattle developed lethargy, anorexia, depression, and recumbency, followed by bellowing, colic, and death. Even though the uneaten contaminated hay was removed the first day, nearly 100 animals died within the first 48 h. Three of these cattle were examined postmortem, and tissues and hay samples were collected for microscopic and chemical analysis. Several days later, a smaller number of the clinically poisoned cattle developed neurologic disease with aberrant behavior, aggression, icterus, blindness, exhaustion, and death. A total of 165 cattle were fatally poisoned. Poisoned cattle had swollen, dark, mottled livers that had a prominent nutmeg-like lobular pattern on cut section. Histologically, there was severe centrilobular-to-panlobular hepatic necrosis with marked hepatocellular swelling, degeneration, and necrosis. The surviving cattle developed liver disease characterized by altered serum biochemical analyses and microscopic hepatocellular degeneration and necrosis. In subsequent biopsies and analysis, these lesions resolved within 6–7 mo. After confirming toxicity of the hay in cattle, goats, and mice, followed by a mouse bioassay–guided chemical fractionation process, Salvia reflexa was identified as the contaminant in the hay responsible for the hepatotoxicity. S. reflexa has not been reported previously to cause fatal hepatotoxicity in livestock in North America, to our knowledge.     

Description of a new procedure to estimate the carbon stocks of all forest pools and impact assessment of methodological choices on the estimates

Forest ecosystems play a major role in atmospheric carbon sequestration and emission. Comparable organic carbon stock estimates at temporal and spatial scales for all forest pools are needed for scientific investigations and political purposes. Therefore, we developed a new carbon stock (CS) estimation procedure that combines forest inventory and soil and litter geodatabases at a regional scale (southern Belgium). This procedure can be implemented in other regions and countries on condition that available external carbon soil and litter data can be linked to forest inventory plots. The presented procedure includes a specific CS estimation method for each of the following forest pools and subpools (in brackets): living biomass (aboveground and belowground), deadwood (dead trees and snags, coarse woody debris and stumps), litter, and soil. The total CS of the forest was estimated at 86 Tg (185 Mg ha^?1). Soil up to 0.2 m depth, living biomass, litter, and deadwood CSs account, respectively, for 48, 47, 4, and 1 % of the total CS. The analysis of the CS variation within the pools across ecoregions and forest types revealed in particular that: (1) the living biomass CS of broadleaved forests exceeds that of coniferous forests, (2) the soil and litter CSs of coniferous forest exceed those of broadleaved forests, and (3) beech stands come at the top in carbon stocking capacity. Because our estimates differ sometimes significantly from the previous studies, we compared different methods and their impacts on the estimates. We demonstrated that estimates may vary highly, from ?16 to +12 %, depending on the selected methods. Methodological choices are thus essential especially for estimating CO₂ fluxes by the stock change approach. The sources of error and the accuracy of the estimates were discussed extensively.     

Abnormal Sysmex XT‐2000iV DIFF scattergram in a cat with a prominent mastocytemia

A 2‐year‐old neutered male domestic shorthair cat was presented to the emergency service of the National Veterinary School of Toulouse (France) for acute vomiting and diarrhea with lethargy, inappetence, and adypsia for the past 48 hours. Complete blood counts were performed with the ProCyte DX at the emergency department and with the Sysmex XT‐2000iV at the laboratory 2 weeks later. The scattergrams from the two analyzers revealed similar unusual and abnormal dot plots. The Sysmex XT‐2000iV DIFF scattergram also showed no clear separation between different leukocyte populations. The eosinophil cluster was in an abnormal location compared with that of the “typical” location in a normal cat. A blood smear evaluation revealed the presence of numerous mast cells. Thus, we hypothesized that the Sysmex XT‐2000iV had detected the mast cell population, and this led to errors in the differential counts. To explore this hypothesis, we manually gated on the DIFF scattergram and performed a manual differential on the blood smear. With this new gating strategy, the Sysmex XT‐2000iV and manual differentials were similar. Thus, in the case of systemic mastocytosis, mast cells can be located between the lymphocyte, monocyte, and eosinophil clusters on scattergrams.     

Effects of potential probiotic <Emphasis Type="Italic">Lactococcus lactis</Emphasis> subsp. <Emphasis Type="Italic">lactis</Emphasis> on digestive enzymatic activities of live feed <Emphasis Type="Italic">Artemia franciscana</Emphasis>

In the present study, cellulase, protease, lipase and amylase activities were performed to investigate the effects of Lactococcus lactis subsp. lactis CF4MRS bioencapsulation of Artemia franciscana. Our results show that cellulase activities (total cellulase—FPase activity, exoglucanase and endoglucanase—CMCase activity) were significantly higher (P < 0.05) in A. franciscana tissue homogenates compared to those in the control group after 8 h of L. lactic bioencapsulation. Notably, an exception case was found in β-D-glucosidase activity, whereby the cellulase activity was not significantly different (P > 0.05) compared to the control group. Administrations of L. lactis at cell concentration of 10⁸ CFU mL^?1 showed considerable improvement of other important enzymatic activities such as amylase, protease and lipase in A. franciscana. The amylase/protease ratio in probiotic-treated A. franciscana was recorded at 0.343, approximately two times higher than those without probiotic administration (0.184). In contrary, amylase/lipase ratio showed half of a reduction (0.330) in L. lactis-administrated A. franciscana compared to the control (0.614). Our study suggests that important digestive enzymes, e.g., cellulase, amylase, protease and lipase, can be enhanced through bioencapsulation of A. franciscana with L. lactis subsp. lactis, which could in turn lead to further stimulation of endogenous enzymes in the fish and shrimp larvae.     

Rescue of dystrophic muscle through U7 snRNA-mediated exon skipping

Most mutations in the dystrophin gene create a frameshift or a stop in the mRNA and are associated with severe Duchenne muscular dystrophy. Exon skipping that naturally occurs at low frequency sometimes eliminates the mutation and leads to the production of a rescued protein. We have achieved persistent exon skipping that removes the mutated exon on the dystrophin messenger mRNA of the mdx mouse, by a single administration of an AAV vector expressing antisense sequences linked to a modified U7 small nuclear RNA. We report the sustained production of functional dystrophin at physiological levels in entire groups of muscles and the correction of the muscular dystrophy.     

Risk factors for Listeria monocytogenes contamination in French laying hens and broiler flocks

The objective of this study was to identify potential risk factors for Listeria monocytogenes contamination in French poultry production. Eighty-four flocks of layer hens kept in cages and 142 broiler flocks were included in this study. For each production type, a questionnaire was submitted to farmers and fecal samples were taken to assess the L. monocytogenes status of the flocks during a single visit to the farm. Two logistic regression models (specific to each production) were used to assess the association between management practices and the risk of L. monocytogenes contamination of the flock. The prevalence of L. monocytogenes-positive flocks was 30.9% (95% CI: 21.0; 40.9) and 31.7% (95% CI: 24.0; 39.4) for cage-layers and broiler flocks, respectively. For layer flocks, the risk of L. monocytogenes contamination was increased when pets were present on the production site. When droppings were evacuated by conveyor belt with deep pit storage, the risk of L. monocytogenes contamination decreased significantly. Feed meal was found to be associated with a higher risk of L. monocytogenes contamination than feed crumb. For broiler flocks, the risk of L. monocytogenes contamination was increased when farmers did not respect the principle of two areas (clean and dirty) at the poultry house entrance. A first disinfection by thermal fogging and the absence of pest control of the poultry house before the arrival of the next flock was found to increase the risk of contamination. When litter was not protected during storage and when farm staff also took care of other broiler chicken houses, the risk of L. monocytogenes contamination increased significantly. In the case of the watering system, nipples with cups were found to decrease the risk of contamination.     

Period of susceptibility of almonds to aflatoxin contamination during development in the orchard

Almonds can be contaminated with aflatoxins, produced mainly by Aspergillus flavus and A. parasiticus. Infection can be facilitated by insect injuries during hull split, which begins four to six weeks before harvest. Within this period, it is unknown which kernel stages are most susceptible to aflatoxin contamination. Developing almonds of the Nonpareil cultivar were inoculated weekly with a spore suspension of A. flavus or A. parasiticus for five weeks after hull split in 2013. The almonds were infested with eggs of the lepidopteron navel orangeworm (NOW) (Amyelois transitella) before each spore inoculation. Aflatoxin levels were quantified at harvest using HPLC. Aflatoxin contamination was consistently higher in NOW-damaged kernels, although aflatoxins were also detected in undamaged kernels at each inoculation date. Insect injury is not required for kernel infection but it is a key risk factor for high aflatoxin contamination. Laboratory inoculations were also performed on Nonpareil almond kernels collected during the summers of 2013 and 2015. Aflatoxin levels were significantly lower on dried almonds but the ability to produce aflatoxins was restored when almonds were incubated with high humidity or when the Aspergillus species were inoculated on almond meal agar amended with ground kernels. Therefore, aflatoxins can accumulate in kernels with low a_w, should sufficient moisture favors aflatoxin production. In our field experiment, the orchard micro-climate had sufficient humidity to enable aflatoxin production in both damaged and undamaged dried kernels.