BACKGROUND: Omega-3 fatty acids can be conducive toreducing the harmful effects of physiological stress through reducing the stimulatory activity of glutamatergic neurons.OBJECTIVES: The aim of this study was to investigate the effects of omega-3 fatty acids on performance, blood parameters, and the profile of fatty acids in the egg yolks of laying hen under stress.METHODS: This study was performed using 96 LSL-Lite laying hens in a 2 × 3 factorial experiment with 2 factors, namely stress (no dexamethasone and 1.5 mg/kg of diet dexamethasone) and omega-3 fatty acids (the levels of 0, 0.24 and 0.48 % of diet), in a completely randomized design for 70 days from 35 to 44 weeks of age.RESULTS: Physiological stress reduced the feed intake, the percentage of egg production, and egg mass in laying hens (P<0.05). Omega-3 fatty acid supplements had no effects on these traits. The groups receiving 0.48 % of omega-3 fatty acids had the lowest heterophil:lymphocytes (P<0.05), and there was no difference between stressed and non-stressed groups. The ratio of omega-6 to omega-3 fatty acids was higher in birds previously affected by stress (P<0.05). Feeding with omega-3 fatty acids in birds increased omega-3 fatty acids in egg yolk and reduced the ratio of omega-6 fatty acids to omega-3 in laying hens (P<0.05).CONCLUSIONS: Based on the results of this experiment, physiological stress had a negative effect on performance traits, and the use of omega-3 fatty acids in laying hens under stress had no effect on performance traits. Physiological stress altered the profile of fatty acids and increased the proportion of omega-6 to omega-3 fatty acids in egg yolk. The use of omega-3 fatty acids reduced the negative effects of stress and improved the profile of fatty acids in egg yolk.

BACKGROUND: Urea is a non-proteinaceous nitrogen source, often used as a substitute for raw ration protein in order to reduce the feeding cost of livestock. OBJECTIVES: The purpose of this study was to investigate the effects of substitution of different levels of slow-release urea with soybean  meal on feed intake, milk production and composition, and blood parameters of lactating cows in early lactation. METHODS: Twelve Holstein cows were selected at the third birthday, milk production of more than 30 kg per day, and from 10 to 100 days after birth, with four diets, the treatments included 0, 23, 0.46 and 0.69  % of slow-release urea was replaced by soybean meal. Feed intake was measured daily. The milk sample was taken on the day of the start of the experiment and was taken at intervals of 14 days. To measure glucose, urea, cholesterol, triglycerides, high density lipoprotein, and low blood levels, were determined  from the start of the test to the end of the test every two weeks. RESULTS: Consumption of feed, milk production and composition did not differ from experimental treatments. Glucose concentration and blood parameters (cholesterol, high and low density lipoprotein) did not differ between experimental treatments, but triglyceride and lipoprotein showed a very low density at zero (P <0.05). CONCLUSIONS: The results of this study showed that adding slow-release urea to the level of 0.69% had no negative effect on feed consumption, milk production and composition, and blood parameters.

BACKGROUND: Comparison between Infectious Bursal Disease vaccines. OBJECTIVES: Comparison between foreign and Iranian intermediate uncloned Gumboro vaccines on feed conversion ratio. METHODS: Three hundred and thirty day-old chicks were purchased and for determination of vaccination time by Deventer formula, thirty chicks were randomly bled and the remaining chicks divided into 3 equal groups, each group was divided into 4 equal subgroups with the same mean weight. On the basis of Elisa results and vaccine instructions, chicks of group 1 and 2 were vaccinated by uncloned intermediate Gumboro vaccine manufactured by Lohman Company, Germany and Razi Vaccine and Serum Research Institute, Iran subsequently at 16 and 23 days by drinking water. One group was kept as unvaccinated control group. Mean feed intake, weight gains, feed conversion ratio and B:B ratio of 3 groups  were determined at 16, 23 and 42 days. At the end of experiment B:B ratio was measured in 3 groups. RESULTS: This study showed that foreign and Iranian intermediate uncloned Gumboro vaccines had negative effect on mean weight gains and both vaccines atrophied bursa of Fabricius, but had no effect on mean feed intake and feed conversion ratio. CONCLUSIONS: This study showed that foreign and Iranian intermediate uncloned Gumboro vaccines had no effect on feed conversion ratio.

Growth indices were examined in 24 identically managed tanks, each containing 120 diploid juvenile rainbow trout (initial mean body weight, 9.3 g), during a 12-week study to examine tank effects associated with tank location in a multi-user research facility. Growth indices included mean body weight, feed intake, feed conversion index, and specific growth rate. The null hypothesis that tank effect had no effect on growth over the 12-week period was rejected (P = 0.038), and mean weight in individual tanks differed by as much as 18.7%. During the study, it was determined that the proximity of tanks to common-use walkways in the facility could affect growth indices. This was indicated by significant differences in the mean fish weights among blocks of tanks served by different header tanks after 4 (P = 0.001) and 8 (P = 0.024) weeks. The block containing tanks of fish with the highest mean weight was nearest to the 2 common-use walkways in the facility. Fish in this block of tanks, compared with those in other blocks, had significantly greater feed intake but no significant differences in conversion efficiency. Compensatory growth, a well known growth attribute in fishes, diminished the difference in mean weight between these blocks of tanks by the end of the study. Comparison of paired tanks within header tank blocks indicated that fish in those located nearest to walkways had higher feeding rates over the 12-week period (P = 0.048), but less efficient teed conversion (P = 0.040) than did fish in matched tanks located farthest from walkways. However, there were no differences in mean weight of fish. Results of this trial document the risks involved in identifying fish in a tank as the experimental unit when treatments are administered to the tank of fish, the latter being the true experimental unit.

Sixteen healthy ponies were inoculated IV with Ehrlichia risticii-infected P388D1 mouse monocytes. Of the 16 ponies, 15 developed clinical signs of equine ehrlichial colitis. Twenty-four hours after onset of fever (rectal temperature > 38.8 degrees C), 7 ponies were treated with 25 mg of erythromycin stearate/kg of body weight and 10 mg of rifampin/kg, given orally every 12 hours for 5 days. The remaining 8 ill ponies served as nontreated controls. All ponies were observed for progression of clinical signs typical of equine ehrlichial colitis. Within 12 hours of initiation of treatment, 4 of the 7 treated ponies had rectal temperature < 38.4 C and, within 24 hours, 6 of the 7 ponies had rectal temperature < 38.3C. In contrast, all control ponies had rectal temperature > 39.2 C at 24 hours (P < 0.05). Of the 7 treated ponies, 4 no longer had signs of mental depression after the second day of treatment, and only 1 of the 7 ponies had mild signs of depression after the third day of treatment. In contrast, control ponies had high mental depression score during the observation period (P < 0.05). Feed intake improved in ponies of the treatment group, with feed intake of 4 of the 7 ponies returning to normal; the other 3 ponies were only mildly anorectic by the second day of treatment. Control ponies progressively decreased their feed intake during the observation period (P < 0.05). One control pony and 2 treated ponies developed diarrhea before the treatment/observation period began. Only 1 treated pony developed diarrhea after treatment began. Of the 8 control ponies, 7 developed diarrhea. Profound decrease in borborygmal sounds with silent periods lasting longer than 3 minutes was observed in 7 of the 8 control ponies. Only 1 of the 7 treated ponies had such profound decrease in borborygmi (P < 0.05). The decrease in borborygmal sounds progressed in the control ponies during the observation period. None of the treated ponies continued to have decreased borborygmi after treatment day 2 (P < 0.05). Of the 8 control ponies, 2 were euthanatized; all treated ponies survived. In survivors, signs lasted 8 to 17 (mean, 10) days in control ponies but only 1 to 5 (mean, 2.9) days in treated ponies.

Renal mass was surgically reduced in 78 dogs by uninephrectomy or by combined renal infarction and uninephrectomy. Renal clearance of inulin and renal clearance of exogenous creatinine were determined simultaneously, and the creatinine to inulin clearance (C/I) ratio was calculated. Clearance procedures were performed 2 to 3 months after reduction of renal mass, and were repeated at intervals thereafter. Overall, the C/I ratio was 1.008 +/- 0.007 for 192 determinations, with a highly significant correlation (R2 = 0.994, P < 0.0001) between creatinine clearance and inulin clearance. There was no significant effect of gender of dogs, time after partial renal ablation, or dietary protein intake on C/I ratios. Degree of renal ablation did not affect C/I ratios. The results indicated that exogenous creatinine clearance is a valid measure of glomerular filtration rate in both male and female dogs with reduced renal mass.

An experiment was conducted to study the effect of citric acid supplementation on growth performance of weaned LWY pigs up to market weight at 205 days. Thirty LWY weaned pigs were selected, divided randomly into five experimental groups and fed with five iso-nitrogenous and iso-calorie ad libitum diets, that contained citric acid at 0, 0.5 %, 1 % and 1.5 % and 2 % of feed. Feed intake was measured daily and body weight was recorded at fortnight intervals. The Escherichia coli count of excreta was estimated for all the weaned pigs for initial, middle and end of the experimental period. The weight gain was significantly (p&lt;0.01) increased by 2.61, 4.59 and 4.74 % at 1 %, 1.5 % and 2 % citric acid supplemented groups than control. The feed intake decreased (p&lt;0.05) and feed conversion efficiency improved (p&lt;0.01) in citric acid supplemented groups as compared to control. Best feed efficiency was observed in 1.5 and 2 % citric acid supplemented groups. The Escherichia coli count in feces was significantly (p&lt;0.01) decreased in citric acid supplemented groups than control and best results were observed in 1.5 and 2 % citric acid supplemented groups. It was concluded that the minimum level of citric acid supplementation at 1.5 % improved the growth performance and cost effectiveness to the maximum extent with lower faecal E. coli count in LWY pigs.

The objective of this study was to evaluate the association between ketonemia and serum paraoxonase-1 (PON1), malondialdehyde (MDA), and other blood components in tail and mammary veins of dairy cows. Forty-two Holstein dairy cows with decreased feed intake were divided into HIGH (≥ 1.2 mM; n = 31) and LOW (< 1.2 mM; n = 11) groups based on the β-hydroxybutyrate concentration in plasma collected from the tail vein. The HIGH group had a significantly greater plasma non-esterified fatty acid (NEFA) concentration, but significantly lower serum PON1 activity and phospholipid concentration, and a tendency to have a lower cholesterol ester concentration than the LOW group. Serum PON1 activity was not correlated with the MDA concentration but was positively correlated with serum concentrations of cholesterol esters and phospholipids, and negatively correlated with the plasma NEFA concentration. These results suggest that serum PON1 activity is reduced by hyperketonemia and the relevance of PON1 to MDA seems to not be direct, though it is involved.

In Malaysia, Guinea grass (Megathrysus maximus) and Napier grass(Pennisetum purpureum) are considered as good palatable fodder for goats and have been used widely. The objective of this study is to evaluate the potential grasses for goats to have optimum growth performance and optimum feeding cost. Fourteen male Jamnapari goats with an average age of five months were used in this experiment. All animals were individually weighed anddivided equally (seven goats) into two treatment groups. Group 1 was fed with cut and carry Guinea grass while group 2 animals were fed cut and carry Napier grass, and both groups were given the same quality and quantity of PKC and molasses. There was no significant difference observed in the average final weight (AFW), average weight gain (AWG) and average daily gain (ADG) among the two dietary treatment group. However, dry matter intake (DMI) and feed conversion ratio (FCR) showed a significant difference. The group fed with Napier grass showed lower ADMI and FCR. From the viewpoint of economic evaluation, feeding Guinea grass and Napier grass as an animal feed is economincally viable for local farmers.