Sandra Nizza

Productive performance and blood profiles of laying hens fed Hermetia illucens larvae meal as total replacement of soybean meal from 24 to 45 weeks of age

&NA; The aim of the research was to study the effects of an insect meal from Hermetia illucens larvae (HILM) as complete replacement of soybean meal (SBM) on productive performance and blood profiles of laying hens, from 24 to 45 wk of age. A total of 108 24‐week‐old Lohmann Brown Classic laying hens was equally divided into 2 groups (54 hens/group, 9 replicates of 6 hens/group). From 24 to 45 wk of age, the groups were fed 2 different isoproteic and isoenergetic diets: the control group (SBM) was fed a corn‐soybean meal based diet, while in the HILM group the soybean meal was completely replaced by Hermetia illucens larvae meal. Feed intake, number of eggs produced, and egg weight were recorded weekly along the trial. At 45 wk of age, blood samples were collected from 2 hens per replicate. The use of HIML led to a more favorable (P < 0.01) feed conversion ratio in hens but lay percentage, feed intake, average egg weight, and egg mass were higher (P < 0.01) in hens fed the SBM diet. Hens fed insect meal produced a higher percentage of eggs from small (S), medium (M), and extra‐large (XL) classes (P < 0.01) than SBM, while the SBM group had a higher percentage of eggs from the large (L) class (P < 0.01). The levels of globulin and albumin to globulin ratio were, respectively, higher and lower (P < 0.05) in HILM than the SBM group. Cholesterol and triglycerides were higher (P < 0.05 and P < 0.01, respectively) in hens from SBM than in the HILM group. Blood levels of Ca were higher (P < 0.01) in hens fed insect meal, while creatinine was higher (P < 0.01) in blood of hens fed SBM. Hermetia illucens larvae meal can be a suitable alternative protein source for laying hens even if the complete replacement of soybean meal needs further investigation to avoid the negative effects on feed intake.

Effect of dietary mannan‐oligosaccharides on in vivo performance, nutrient digestibility and caecal content characteristics of growing rabbits

To evaluate the effect of mannan-oligosaccharides (MOS) on in vivo performance, nutrient digestibility, fermentation characteristics and caecal microbial populations of rabbits, 144 thirty-five days old hybrid Hyla were equally divided into three groups, one of which was fed the same diet without additives (control group), one with antibiotics (colistin sulphate, 144 mg/kg; tylosin, 100 mg/kg; oxytetracyclin, 1000 mg/kg) and one with MOS (1 g/kg of diet). Mortality rate, live weight, feed intake and feed conversion ratio were recorded up to 62 days of age. At 60 days nutrient digestibility was measured by acid insoluble ash method. The caecal content of 10 rabbits per group was collected at 62 days and analysed for volatile fatty acids production, ammonia content and microbial count. Rabbits from the control group had a significantly (p < 0.01) lower body weight at 62 days (1638.9 g vs. 1779.4 g and 1862.5 g, respectively for the control, MOS and antibiotic groups) while the antibiotic group showed a higher (p < 0.05) feed intake than the control group (127.9 g/day vs. 109.3 g/day). Rabbits from the MOS group had a higher apparent digestibility of cellulose (34.27% vs. 29.61% and 27.49%, respectively for the MOS, control and antibiotic groups) and, as a consequence a higher level of acetate in the caecal content (39.93 mmol/l vs. 34.21 mmol/l and 23.09 mmol/l, respectively for the MOS, control and antibiotic groups). Caecal microflora of the MOS group rabbits also had a higher fermentative activity in respect of protein source, as demonstrated by the higher productions of branched chain fatty acids. MOS and antibiotics significantly reduced the colonies of Coliformis (2.32 vs. 3.20 vs. 2.40 logCFU/g, respectively for the MOS, control and antibiotic groups, p < 0.01). Mannan-oligosaccharides at 1 g/kg of diet can be used as an alternative to antibiotics during the rabbits growth period.

Innate immune response in human keratinocytes infected by a feline isolate of Malassezia pachydermatis

Malassezia pachydermatis is a normal inhabitant of canine and feline skin that can spread to other pets. The outer layer or epidermis is made up primarily of keratinocytes, which are capable of releasing various factors and expressing receptors that are significantly involved in the immune regulation. Little is known about the mechanism by which M. pachydermatis overcomes the natural barrier of the skin. The aim of this study was to evaluate the direct in vitro interaction between human keratinocytes and a clinical strain of live M. pachydermatis isolated as a pure culture from an otitic cat. Human keratinocytes (HaCat) were infected with M. pachydermatis to analyse the modulation of the innate immune response. Gene expression was analysed by real-time PCR. We demonstrated that M. pachydermatis invaded HaCat cells and modulated the expression of TLR2 after 24h infection, while HBD-2, IL-1β TNF-α, IL-6 and IL-8 were modulated both at 24 and 48 h. Thus, our results demonstrated that M. pachydermatis is able to stimulate the innate immune response in infected human keratinocytes indicating a possible role of this yeast as a human opportunistic pathogen.

A comparative evaluation of methicillin-resistant staphylococci isolated from harness racing-horses, breeding mares and riding-horses in Italy

OBJECTIVE To investigate the prevalence of methicillin-resistant staphylococci (MRS) which is a potencial risk factor of transmission between animals and humans in different types of horses (harness racing-horses, breeding mares and riding-horses) and to compare the antimicrobial resistance of the isolates. METHODS A total of 191 healthy horses, housed at different locations of the Campania Region (Italy), were included in the study. Nasal swab samples were collected from each nostril of the horses. The mecA gene was detected by a nested PCR technique. Antibiotic susceptibility was tested for each isolate. RESULTS MRS was isolated from nasal samples of 68/191 (35.6%; 95% CI: 28.9%-42.9%) healthy horses. All isolates were coagulase-negative with the exception of two coagulase-positive MRS strains, identified as Staphylococcus aureus and Staphylococcus pseudintermedius, 2/83 (2.4%; 95% CI: 0.4%-9.2%). Interestingly, both coagulase-positive MRS isolates were from harness racing-horses. These horses also presented a significantly higher positivity for MRS (53.3%; 95% CI: 40.1%-66.1%) than the breeding mares and riding-horses groups. Antibiotic susceptibility testing showed difference between isolates due to different origins except for an almost common high resistance to aminopenicillins, such as ampicillin and amoxicillin. CONCLUSIONS It can be concluded that harness racing-horses may act as a significant reservoir of MRS as compared to breeding mares and riding-horses.

Growth performance, blood profiles and carcass traits of Barbary partridge (Alectoris barbara) fed two different insect larvae meals (Tenebrio molitor and Hermetia illucens)

To investigate the effect of two insect meals (from Hermetia illucens, HI and Tenebrio molitor, TM larvae) on productive performance and blood profiles of Barbary partridge, ninety, seven days old partridges were divided into 5 groups (6 replicates, 3 partridges/replicate). Up to 64d, the groups fed 5 isoproteic and isoenergetic diets: the control fed a corn-soybean meal diet (SBM group); in TM25 and TM50 groups the 25 and 50% of SBM proteins were substituted by the protein from TM, respectively; in HI25 and HI50 groups the 25 and 50% of SBM were substituted by the protein from HI, respectively. The birds fed TM25 and both the HI levels reached a higher (P<0.01) live weight at 64d than the control. Considering the entire experimental period the TM groups had a more favorable FCR than SBM. The carcass weights of all the insect groups were higher (P<0.01) than the control. The weight of the full digestive tract in SBM group was the highest (P<0.01). The caecal weight, the intestinal and caecal length were the highest (P<0.01) in the SBM group. The SBM group the highest value of albumin/globulin (P<0.01) and creatinine (P<0.05). TM seems to be more effective than HI in improving FCR. The reduced albumin/globulin ratio in the insect meal fed groups could be ascribed to the chitin content and this result was not affected by the amount of chitin intake, suggesting that also the lowest values are able to express their potential effects in partridges.

Effect of spray application of Lactobacillus plantarum on in vivo performance, caecal fermentations and haematological traits of suckling rabbits

Two days before kindling, 228 New Zealand White rabbit does were homogeneously divided into two groups (114 does per group) and fed the same diet. After delivery, the litters were equalized to 8 pups. From 1 to 35 days of age (weaning), the control group (CONT) did not receive any treatment while in the experimental group (LAC) the nests were sprayed with a commercial product containing lyophilized Lactobacillus plantarum dissolved in water (12 g/L). L. plantarum was sprayed on the litters (5 mL per rabbit) once a day during seven consecutive days after delivery. After one week of rest, the treatment was repeated for another week according to the same experimental protocol. Mortality rate, recorded on all the litters (912 rabbits per group) was significantly lower in the LAC group (9.9 vs 17.2%; P<0.05). There were no significant differences in in vivo performance of the 24 litters per group, and rabbits of both groups reached a similar weight at weaning (938 vs 932 g for LAC and CONT groups, respectively). Rabbits from the LAC group showed fermentative activity of caecal microflora (total volatile fatty acids 24.8 vs 14.5 mmol/L; P<0.01) and higher percentage of lymphocytes (73.7 vs 63.9% of total white blood cells; P<0.05). Among the microflora population of rabbit caecal content from the LAC group, it was possible to identify L. plantarum (1.25×106 CFU/g). It might be supposed that the changes in caecal microflora can affect our results and improve the sanitary status of Lactobacillus-sprayed rabbits in the period 1–35 days of age.

Streptococcus constellatus-associated pyoderma in a dog.

This report describes a case of chronic and deep pyodermitis in a 4-year-old male dog with a 3-month skin problems history that had been treated unsuccessfully with fluoroquinolone therapy, prescribed by a private medical veterinary practice, without an early diagnosis. Microbiological examination and antimicrobial susceptibility testing were performed in our laboratory (Faculty of Veterinary Medicine) and a diagnosis of Streptococcus constellatus-associated pyoderma in the dog was made. A new antimicrobial treatment, with tetracyclines, was designed after the definitive diagnosis and antimicrobial susceptibility testing performed by the Kirby-Bauer disc diffusion method. The dog remained free of clinical illness at completion of therapy. To our knowledge, this is the first case of a canine pyoderma caused by S. constellatus, a commensal organism which may also cause pyogenic infections. Furthermore, this study confirms that a fluoroquinolone represents a poor empirical choice for initial therapy of canine pyoderma.

In vitro growth versus inhibition of growth of Malassezia pachydermatis in the presence of the antibacterial drug gentamicin.

Malassezia pachydermatis is part of the normal cutaneous microbiota of most warm-blooded vertebrates and is associated with otitis externa and seborrhoeic dermatitis in dogs and cats. In this study, we evaluated the growth capacity of nine M. pachydermatis strains on Sabouraud medium in the presence of a high concentration of gentamicin. Strains of M. pachydermatis cultured on Sabouraud medium in the presence of 50 and 100 µg gentamicin ml(-1) displayed different growth patterns such as growth or lack of growth. We hypothesized that this difference in growth of M. pachydermatis strains was correlated with the different genotypes of the strains. Random amplification of polymorphic DNA (RAPD) was applied for genetic typing of M. pachydermatis isolates, derived from the external ears of house pet cats suffering from otitis externa. The M. pachydermatis strains were cultured on commercial or home-made Sabouraud medium supplemented or not with gentamicin. RAPD analysis demonstrated a genetic heterogeneity between each strain. In particular, five out of nine strains tested were able to form colonies in the presence of gentamicin. However, a correlation between M. pachydermatis genotype and growth capacity in the presence of gentamicin was not widely demonstrated.

Prediction of digestible energy and gross energy digestibility of feeds and diets in ostriches.

Abstract 1. The aim of this study was to assess regression equations able to predict the digestible energy (DE) and gross energy digestibility (GEd) of feed ingredients and diets for ostriches. 2. Results of chemical-nutritional characteristics from 17 ingredients (two varieties of maize, two barleys, oat, triticale, wheat bran, soybean meal, sunflower meal, beet pulp, maize silage, alfalfa hay, 4 alfalfa meals and lupin) and 12 experimental diets were used in a stepwise procedure. 3. Acid detergent lignin (ADL) was the first independent variable included in the model to predict the DE of all the samples (R2 = 0.65 and Residual Standard Deviation (RSD) 1.02). When the concentration of ash, acid detergent fibre (ADF) and crude fibre were included in the model, the R2 value of the regression equation increased (from 0.65 to 0.85) and RSD decreased (from 1.02 to 0.48). 4. The ADL concentration was also the first independent variable chosen by the stepwise regression analysis for the estimation of GEd from chemical-nutritional characteristics of feeds, explaining 57% of the total GEd variation. The concentrations of crude protein and ADF included at the second and third steps in the model increased the R2 (up to 0.70 and 0.73, respectively) and decreased the RSD values (from 0.29 to 0.21 and 0.20, respectively). When other variables as crude fibre, ash and gross energy were included in the model, the coefficient of determination and the RSD strongly improved (0.85 and 0.12, respectively).

Estimated prevalence of Johne’s disease in herds of water buffaloes (Bubalus bubalis) in the province of Caserta

Paratuberculosis is a chronic infection of domestic and wild ruminants, caused by Mycobacterium avium subsp. paratuberculosis. The persistence of paratuberculosis infection for months up to years without exhibiting any clinical signs makes the diagnosis and control program a difficult proposition. Limited informations on prevalence of paratuberculosis in water buffaloes (Bubalus bubalis) are available. We carried out a study on 1350 buffaloes belonging to 56 herds in the Caserta province, of Campania region, Italy. The prevalence of infected buffalo dairy herds was estimated by a commercial ELISA kit of individual blood samples of animals over 24 months of age. On the basis of performance (sensitivity 43%, specificity 99.3%) of ELISA test on serum, the resulting true prevalence at animal level and at herd level was 4% (95% CI 3% to 5%) and 74,1% (95% CI 71.8% to 76%). Considering the paucity of epidemiological reports in the region our results could be a useful contribution towards the prevention of buffalo paratuberculosis in the area.