Iranian Journal of Veterinary Research
Volume:13 Issue: 4, Autumn 2012

Nowadays، uncontrolled and frequent use of antibiotics may cause emergence of microbial resistance among pathogenic agents. Therefore، the use of new synthetic and natural antimicrobial compounds is inevitable. One source of natural compounds in this respect comes from plants. The purpose of this study as to examine the antibacterial effects of peel extracts from sour and sweet pomegranate. Methanolic extracts of sour and sweet pomegranate peels and aqueous solutions of tetracycline and chloramphenicol were prepared. Antibiogram tests using disk diffusion technique and serial dilution method were performed against ten pathogenic bacteria isolated from animals، and relative minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) values were also determined for the above compounds. The greatest zone of inhibition induced by the action of pomegranate peel extracts was obtained for Staphylococcus aureus (about 25 mm) and the smallest zone of inhibition was obtained for Pasteurella multocida (about 9 mm). In addition، the lowest MIC and MBC values of pomegranate peel extract were obtained for Staphylococcus aureus (7. 8 and 62. 5 mg/ml، respectively). Results of serial dilution tests indicate that bactericidal effect of sour pomegranate peel extract was more than that for sweet pomegranate peel extract; and sweet pomegranate peel extract exerts a bacteriostatic action against bacteria. The antibacterial effect was greater against Gram-positive bacteria compared to that for the Gram-negative bacteria. Effects of these extracts were considerably lower than those for tetracycline and chloramphenicol. In conclusion، methanolic extracts of pomegranate peels exhibit relatively good bacteriostatic and bactericidal effects.

This study was conducted to evaluate the effects of inoculation of homo-fermentative lactic acid bacteria (LAB) on ensiling characteristics and nutritive value of low dry matter corn silage (LDMCS). Corn forage was harvested at milk stage (22. 8 ± 0. 9% DM)، chopped at theoretical length of cut (TLC) 2. 5 cm، and stored in eighteen 3. 8 L mini silos for each treatment. The following treatments were used، 1) control (uninoculated)، 2) ecosyl (treated with ecosylTM corn silage inoculants containing Lactobacillus plantarum)، and 3) biotal (treated with biotalTM corn silage inoculants containing Lactobacillus plantarum، Pediococcus pentosaceus and Propionibacter freudenreichii). Triplicate silos for each treatment were opened and sampled for chemical analyses after 3، 6، 12، 16، 21 and 90 days of ensiling. Neither ecosyl nor biotal improved fermentation characteristics of LDMCS compared to the control silage. Neutral detergent fiber (NDF)، acid detergent fiber (ADF)، crude protein (CP)، water soluble carbohydrate (WSC) contents and lactic acid (LA) concentration were not affected significantly by inoculants (P>0. 05). Acetic acid concentration of control silages was higher; however، ethanol concentration was lower than the other silages. Biotal treated silages had the highest ammonia-N (NH3-N) concentrations compared to the control (P<0. 05). In vitro dry matterdisappearance (IVDMD) of control silage was higher than treated silages (P<0. 05). In conclusion، the results showed that homo-fermentative LAB inoculants used in this experiment did not improve the fermentation characteristics and nutritive value of LDMCS.

The present study evaluated the effects of diets enriched in saturated and polyunsaturated fatty acids (n-3 and n-6) on reproductive indices، metabolic hormones and metabolites prior to ram introduction in oestrus synchronized ewes. Zel ewes (n=188) were assigned to 4 groups. Ewes in the control group (CON) did not receive fat. Ewes in the 3 other groups received 3% oil/DM/day of palmolein oil (PLM)، safflower seed (SAF)، or flaxseed (FLX). Fat supplementation was carried out for 31 days (day 0 = initiation of fat supplementation). Oestrus was synchronized using CIDR for 14 days starting from day 16 of fat supplementation. Rams were introduced 24 h after CIDR removal. Blood samples were collected on days 0،30، and 39. There was no difference in oestrus expression and mating parameters among groups. There was no difference in non-esterified fatty acids (NEFAs)، insulin and insulin-like growth factor-1 (IGF-1) between day 0 and day 30 among groups. However، changes in cholesterol and LDL concentrations during the same occasions were greater in PLM، SAF، and FLX groups than in CON (P<0. 05). There was no difference in reproductive indices، including: fertility rates، prolificacy and sex ratio of lambs among groups. In conclusion، diets enriched in n-6 and n-3 polyunsaturated fatty acid prior to mating did not affect reproductive performance، insulin، IGF-1 and progesterone in Zel sheep.