Protection against myxomatosis and rabbit viral hemorrhagic disease with recombinant myxoma viruses expressing rabbit hemorrhagic disease virus capsid protein

Two myxoma virus-rabbit hemorrhagic disease virus (RHDV) recombinant viruses were constructed with the SG33 strain of myxoma virus to protect rabbits against myxomatosis and rabbit viral hemorrhagic disease. These recombinant viruses expressed the RHDV capsid protein (VP60). The recombinant protein, which is 60 kDa in size, was antigenic, as revealed by its reaction in immunoprecipitation with antibodies raised against RHDV. Both recombinant viruses induced high levels of RHDV- and myxoma virus-specific antibodies in rabbits after immunization. Inoculations by the intradermal route protected animals against virulent RHDV and myxoma virus challenges

Feeding behaviour of the growing rabbit fed freely or restricted, and impact on performances and digestive organs

[EN] This study aimed to determine how rabbits feeding and drinking behaviour was influenced by a feed restriction programme, and how performance and the morphometry of the digestive tract and lymphoid organs were influenced. At weaning (28 d old), 432 rabbits were housed in cages of 6, and allotted to 2 groups according to feed intake level: ad libitum feeding (AL group) from 28 to 72 d old, and feed intake (R group) restricted to 70% of AL intake from 28 till 49 d old, followed by ad libitum feeding from 50 till 72 d old. During the restriction, the R group intake was 36% lower than that of the AL group. When returning to an ad libitum feeding, the R group intake increased by 270%, thus exceeding the AL intake by 26% (P=0.03). The daily weight gain was reduced by 28% for R group during the restriction (40.0 vs. 55.7 g/d; P<0.001), whereas the feed conversion was improved (-11%, 1.86 vs. 2.09; P<0.001). The restriction led to a shorter intestine (-15%, 202 vs. 233; P<0.05) and lighter spleen (-15%, 4.8 vs. 5.9; P<0.05), whereas the number of Peyer patches was not influenced. Most of the growth delays of lymphoid tissues observed at the end of the restriction period in the R rabbits remained until the end of the experiment. The feeding activity of AL rabbits mainly occurred during the dark period (19:00-09:00), with 16% of rabbits eating. The R group strongly and massively started their feeding activity at feed distribution time (8:30-09:00), with 65% of rabbit eating at the start, then 35% still eating half an hour later. Feeding activity of R group remained high for 8 h after the feed distribution, with 28% of rabbits having a feeding activity between 9:30 and 17:00. R group had a higher number of meals (+30%) and drinks (+28%), and a longer meal duration (+30%) compared to AL group. R group consumed 63% of the intake within 6-7 h compared to ad libitum fed rabbits, which spread their intake over 15 h. No changes in social behaviour (access to feed or drinking, resting, aggressiveness) were detected, suggesting that this restriction programme did not impair welfare compared to that of ad libitum fed animals.Martignon, M.; Burel, C.; Guinebretière, M.; Postollec, G.; Huonnic, D.; Boilletot, E.; Michel, V.... (2022). Feeding behaviour of the growing rabbit fed freely or restricted, and impact on performances and digestive organs. World Rabbit Science. 30(2):119-130. https://doi.org/10.4995/wrs.2022.14513OJS11913030

Effect of low dose of fumonisins on pig health: Immune status, intestinal microbiota and sensitivity to Salmonella

The objective of this study was to measure the effects of chronic exposure to fumonisins via the ingestion of feed containing naturally contaminated corn in growing pigs infected or not with Salmonella spp. This exposure to a moderate dietary concentration of fumonisins (11.8 ppm) was sufficient to induce a biological effect in pigs (Sa/So ratio), but no mortality or pathology was observed over 63 days of exposure. No mortality or related clinical signs, even in cases of inoculation with Salmonella (5 x 10(4) CFU), were observed either. Fumonisins, at these concentrations, did not affect the ability of lymphocytes to proliferate in the presence of mitogens, but after seven days post-inoculation they led to inhibition of the ability of specific Salmonella lymphocytes to proliferate following exposure to a specific Salmonella antigen. However, the ingestion of fumonisins had no impact on Salmonella translocation or seroconversion in inoculated pigs. The inoculation of Salmonella did not affect faecal microbiota profiles, but exposure to moderate concentrations of fumonisins transiently affected the digestive microbiota balance. In cases of co-infection with fumonisins and Salmonella, the microbiota profiles were rapidly and clearly modified as early as 48 h post-Salmonella inoculation. Therefore under these experimental conditions, exposure to an average concentration of fumonisins in naturally contaminated feed had no effect on pig health but did affect the digestive microbiota balance, with Salmonella exposure amplifying this phenomenon

Effect of lactic acid bacteria based product on broilers from the farm to the processing plant

Effect of lactic acid bacteria based product on broilers from the farm to the processing plan

Progression-free survival in children with optic pathway tumors: dependence on age and the quality of the response to chemotherapy--results of the first French prospective study for the French Society of Pediatric Oncology.

PURPOSE: To evaluate a strategy aimed at avoiding radiotherapy during first-line treatment of children with progressive optic pathway tumors (OPT), by exclusively administering multiagent chemotherapy during 16 months. PATIENTS AND METHODS: Between 1990 and 1998, 85 children with progressive OPT were enrolled onto this multicenter nationwide trial. Chemotherapy alternating procarbazine plus carboplatin, etoposide plus cisplatin, and vincristine plus cyclophosphamide was given every 3 weeks. At the time of relapse or progression, second-line chemotherapy was authorized before recourse to radiotherapy. RESULTS: Objective response rate (partial response [PR] + complete response [CR]) to chemotherapy was 42%. Five-year progression-free survival (PFS) and overall survival rates were 34% and 89%, respectively. The 5-year radiotherapy-free survival rate was 61%. In the multivariate analysis of the 85 patients that entered onto the study, factors associated with the risk of disease progression were age younger than 1 year at diagnosis (P =.047) and absence of neurofibromatosis type 1 (P =.035). In the multivariate analysis of the 74 patients that remained on study after the first cycle of chemotherapy, factors associated with the risk of disease progression were age younger than 1 year at diagnosis (P =.0053) and no objective response to chemotherapy (P =.0029). Three-year PFS was 44% in infants < or = 1 year versus 66% in children older than 1 year. Three-year PFS was 53% in the absence of an objective response to chemotherapy versus 68% after a PR or CR. CONCLUSION: A significant proportion of children with OPT can avoid radiotherapy after prolonged chemotherapy. Deferring irradiation with chemotherapy protocols did not compromise overall survival of the entire population or visual function.Journal ArticleMulticenter StudyResearch Support, Non-U.S. Gov'tinfo:eu-repo/semantics/publishe