Effects of supplementation with sodium caseinate of early lactation diet on performance, digestibility, microbial nitrogen flow, and nitrogen efficiency in Holstein cows

Performance, digestibility of nutrients, microbial nitrogen flow [MNF] and nitrogen efficiency [NE] in early lactating Holstein cows were investigated by diet supplementation with sodium caseinate [CN]

Multiparous lactating Holstein cows [n = 15] with an average body weight of 638 kg and 21 days in milk were assigned to a completely randomized design [five cows per treatment] and fed a basal diet with different CN levels [treatments 1, 2, and 3, contained 0, 50, and 100, g/d/head CN, respectively]. The study lasted 49 days [first 14 days for adaptation and the last 35 days for collection of data]

There were no statistical differences in dry matter intake, milk yield, milk lactose yield, and protein yield with CN supplementation

3.5% fat corrected milk yield was increased by CN supplementation [P<0.05] Digestibility of ADF was increased by CN supplementation [P<0.05]

The higher level of CN affected MNF was estimated by spot urine sampling technique [P<0.05]

Predicted N excretion through urine was affected [P<0.05]; however, there was no effect of CN supply on predicted N excretion through faeces. In conclusion, the results indicated that although supplementation with CN improved MNF, negligible effects on performance of the cows were observed. Furthermore, increased milk urea nitrogen [MUN] concentration and predicted urine N excretion revealed the lower NE in early lactating dairy cows supplemented with CN compared with control treatment?

[ effects of saccharomyces cerevisiae and lactic acid producing bacteria on digestibility, rumen and blood parameters of sheep]

Various probiotic products have been used in ruminant nutrition over the past decade. Some of them had positive effects on animal production. Present study was conducted to investigate the effects of Saccharomyces cerevisiae, Lactobacillus acidophilus, Lactobacillus casei, Enterococcus faecium, Bacillus subtilis mixture on digestibility, rumen and blood parameters of 4 fistulated varamini sheeps. Animals fed with 4 diets during 4 periods using a 2x2 factorial arrangement in a change-over design. First factor included two sources of forages [alfalfa hay and corn silage] and second factor included two levels of above probiotic mixture [0 and 5 gr/day/head]. Digestibility of diets were measured by acid insoluble ash as marker. Blood samples were taken at 0 and 4 hours after feeding via jugular vein to determine concentration of CO2, pH, LDH and Glucose. Also ruminal liquor samples were taken at 0 and 4 hours after feeding to determine rumen pH and concentration of N-NH3 and volatile fatty acids. The results showed that digestibility of acid detergent fiber, neutral detergent fiber, organic matter and dry matter of diets were not significantly different among diets. However, digestibility of crude protein and ether extract in diets containing corn silage were lower and higher than alfalfa hay, respectively. There was no significant difference on blood metabolites of sheep fed various diets. Total volatile fatty acids in sheep fed microbial mixture were more than control group. Diets containing alfalfa hay had higher propionate and acetate concentrations than diets containing corn silage. Ruminal ammonia concentration decreased in sheep fed diets containing microbial mixture [P<0.05]. We concluded that present microbial mixture improved ruminal fermentation but could not significantly affect digestibility and blood metabolites of sheep

[Effects of natuzyme dietary supplements on feedlot performance, feed digestibility and rumen metabolities in Varamini male lambs]

Different supplementary enzymes have used widely in diets for ruminants and non-ruminants over the past decade. The present study investigated the effect of feeding natuzyme [enzyme supplement] on feedlot performance, feed digestibility and rumen metabolites of Varamini male lambs. Twenty-four Varamini male lambs [initial body weight 22 +/- 1.5 Kg with 3 to 4 months age] used in a completely randomized design for 84 days. The lambs were randomly allocated to three rations of 1] without enzyme, control diet, 2] with 0.5 g/kg of feed natuzyme, 3] with 1 g/kg of feednatuzyme with 8 replication. Basal diet was formulated according to CNCPS for sheep. Daily dry matter intake and monthly average gain of lambs recorded and digestibility of basal diet measured with chromic oxide as external marker. At the end of examination, rumen liquid samples collected from lambs and its pH and ammonia nitrogen were measured. The results showed that diets did not make significant effect on the average daily gain, dry matter intake and feed conversion ratio in lambs. Meanwhile, digestibility of crude protein, ether extract, dry matter, organic matter, neutral detergent fiber and acid detergent fiber of basal diet, ruminal pH and ammonia nitrogen did not show difference between diets. We concluded that use of 0.5 or 1 g/kg of feed natuzyme did not make significant effect on the performance of Varamini male lambs

[Survey of blood selenium dependent glutathione peroxidase activity in grazing ewes]

This study was conducted to determining the GPX, Hemoglobin concentration [Hb] and hematocrite percentage [Hct] in blood samples of young ewes were gathered at different places of Zagheh Salman pastures in Qom province. 15 blood samples were gathered through 8 flocks during autumn, winter and spring seasons randomly. At first the measures of GPX, Hb and Hct were determined and then GPX concentration in the basis of unit per gram of hemoglobin and unit per milliliter of hematocrite were calculated. Data were analyzed using SPSS software. Results showed that the ratios of GPX to hemoglobin concentration [GPX/Hb] and hematocrite percentage [GPX/Hct] were higher than their marginal levels significantly.There were significant differences between three seasons for hematocrite percentage and the ratios of GPX to hemoglobin [GPX/Hb] and hematocrite [GPX/Hct].The mean of hematocrite percentage had a maximum level in spring and minimum in winter. The ratios of GPX to hemoglobin and hematocrite had a maximum level in autumn and minimum in spring. The results of this research indicate that, despite of differences between flock and seasons all of flock had higher amounts of mentioned blood factors than their marginal levels and they had no deficiency aspects for these blood factors