Marìa Antonia Mariezcurrena-Berasain

Effects of exogenous enzymes, Lactobacillus acidophilus or their combination on feed performance response and carcass characteristics of rabbits fed sugarcane bagasse

Abstract The aim of this study was to evaluate the effect of Lactobacillus acidophilus (LAC), exogenous enzymes of ZAD® (exogenous enzyme preparation) or their combination on feed conversion, and dressing of rabbits fed different treatments of sugarcane bagasse (SCB). Five rations were allotted randomly to five groups of New-Zealand White (NZW) rabbits ( n =10) with initial live body weight of (838±42.4) g and 5 weeks of age. Rabbits were fed on diets with different sources of fiber as follows, (i) a control diet composed of 100% berseem hay and 0% SCB, (ii) 50% berseem hay and 50% untreated SCB (USCB), (iii) 50% berseem hay and 50% SCB treated with L. acidophilus (LAC), (iv) 50% berseem hay and 50% SCB treated with ZAD® (ZAD), and (v) 50% berseem hay and 50% SCB treated with a combination of LAC+ZAD® (LZ). Treatments of SCB with L. acidophilus , ZAD® and LAC+ZAD® had the highest feed conversion ratio than both USCB and control. The dressing percentage of rabbits that fed the LAC and LZ diets was higher ( P P P L. acidophilus , exogenous enzymes of ZAD® or their combination improved feed conversion and performance with more positive effects with L. acidophilus than the other treatments.

Effect of Organic Selenium-Enriched Yeast Supplementation in Finishing Sheep Diet on Carcasses Microbiological Contamination and Meat Physical Characteristics

The aim of the current study was to evaluate the effect of feeding Pelibuey sheep on diet supplemented with different doses of organic selenium (Se)-enriched yeast on carcasses microbiological contamination and meat physical characteristics. The experiment was conducted during the finishing stage of 18 female sheep and lasted for 60 days. In a complete randomized design, sheep were distributed to one of three treatments: the control without Se-yeast (T1), the control supplemented with Se-yeast at 0.35 mg Se/kg DM (T2), and control supplemented with Se-yeast at 0.60 mg Se/kg DM (T3). The yeast product used was Selyeast 3000TM yeast (LFA Lesaffre, Toluca, Mexico) with a Se concentration of 3000 ppm (mg/kg). Lambs were slaughtered at the end of the experiment at an average weight of 39.5±4.41 kg and samples were taken for microbiological analysis. There were no differences between treatments (P>0.05) and the aerobic plate counts for T1, T2 and T3 had indexes of 0.10, 0.08 and 0.08 log10CFU/cm2, respectively. Total coliform counts obtained were 0.13, 0.10 and 0.09 log10 CFU/cm2 for T1, T2 and T3, respectively, and the faecal coliform counts were 0.09 log10CFU/cm2 for T1, 0.06 log10CFU/cm2 for T2 and 0.07 log10 CFU/cm2 for T3. No significant effects (P>0.05) were observed for carcasses physical characteristics of microbial growth, initial and ultimate pH and temperature, colour values and water holding capacity. It can therefore be concluded that organic Se-enriched yeast did not affect carcasses bacterial proliferation or meat physical characteristics.

Role of dose dependent Escherichia coli as ruminal anti-microflora agent to mitigate biogases production in prickly pear cactus flour based diet

The present investigation was conducted to evaluate the effects of Escherichia coli against the ruminal microflora fermentation activities in the mitigation of CH4 and CO2 production as well as ruminal fermentation kinetics by substituting dietary corn grain with prickly pear cactus (PC) flour. Three total mixed PC rations were prepared (/kg DM): 0 g (Control), 75 g (PC75), and 150 g (PC150). Besides, E. coli was supplemented at four different levels (dose): 0, 10, 20, and 40 mg/g DM of substrates. The in vitro rumen GP, CH4, and CO2 were estimated to be affected due to various doses of E. coli up to 72 h of incubation. Asymptotic GP, fractional rate of GP, and lag time were influenced significantly (P < .05) in the presence of ration. However, E. coli doses showed minor impact on the rate of GP as well as lag time. The asymptotic CH4 production was decreased linearly (P = .005) at the ration PC150. E. coli doses reduced the asymptotic CH4 production at 10 and 20 mg/g DM. The asymptotic CO2 production was linearly (P < .001) decreased by different levels of PC. The cubic (P = .023) effect of E. coli doses as well as significant (P = .002) ration × E. coli doses impact were reported on asymptotic CO2 production. The fractional rate of GP was quadratically (P < .05) influenced by PC and E. coli doses. The rations, dose, and rations × E. coli dose interaction had no influence (P > .05) on lag time. In a nutshell, PC flour inclusion in diet has the potentiality to replace the existing conventional feedstuffs for ruminant. Most importantly, revealing the first report, PC flours along with E. coli supplementation at varied doses mitigated the ruminal biogases production. This was as consequence to the antimicrobial impacts of E. coli against ruminal microflora, and that could certainly be a promising approach in order to improve ruminants diet constituents.

Sensitivity of Coriandrum sativum extract on bacterial pathogens isolated from digestive system of rabbits, and its role on in vitro cecal gas production and fermentation

The present context was aimed to investigate the antibacterial potency of aqueous extract of coriander (Coriandrum sativum L.) leaves against bacterial pathogens isolated from the organs associated with digestive system of rabbit. This study also evaluated the influence of varied doses of aqueous extract of C. sativum (AECS) leaves on in vitro gas production (GP), methane (CH4) production, and some other pivotal fermentation parameters from caecal sample of rabbits. The pathogenic bacteria were isolated from mouth, caecum, and anus of rabbits, and further identified through morphological, biochemical, and molecular tools. The growth inhibitory characteristics of AECS against pathogens were determined using disc diffusion assay. Surprisingly, the result revealed lack of antibacterial potential at tested concentrations. Further, in order to demonstrate the in vitro GP and fermentation parameters in rabbits, four treatments comprising of 0, 0.6, 1.2, and 1.8 mL extract/g dry matter (DM) of AECS were used. Results showed no linear or quadratic effect (P > 0.05) on in vitro GP and CH4 production after the supplementation of AECS in the feeding diet. However, the inclusion of AECS at the concentration of 1.8 mL/g DM exhibited the lowest asymptotic CH4 production and initial delay prior to CH4 production. Similarly, the addition of AECS at 1.8 mL/g DM concentration reduced asymptotic GP as well as CH4 production, and improved fermentation parameters of rabbits when compared with the control and other tested doses. In a nutshell, the tested doses of AECS showed lack of antibacterial trait against the pathogenic bacteria isolated from mouth, caecum, and anus of rabbits. Besides, the AECS exhibited the unique potentiality of reducing GP and improving diversified fermentation parameters in rabbits, thereby suggesting its plausible role as an alternative to commercially available growth promoters in livestock industries.