Influence of spray-dried rumen fluid supplementation on performance, blood metabolites and cytokines in suckling Holstein calves.

Rumen fluid from slaughtered animals is one of the wastes of slaughterhouses released to the environment that, due to its high nitrogen and phosphorus contents, can lead to soil and groundwater pollution. Meanwhile, it contains ruminal microbes and some bioactive compounds such as enzymes, minerals, vitamins and organic acids. This study was designed to examine the potential of rumen fluid as a feed additive. Therefore, the effects of spray-dried rumen fluid (SDR) with 1% maltodextrin on the performance, blood metabolites and some cytokines of sucking dairy calves during the pre-weaning phase were investigated. Forty male Holstein calves, with a mean weight of 39.4 ± 3.7 kg and 7 ± 1 days old, were randomly assigned to four groups (n = 10 calves per group) in a completely randomized design. Experimental treatments were: control diet with no additive (CON); control diet with 0.5 g/day of SDR (SDR0.5); control diet with 1 g/day of SDR (SDR1); and control diet with 1.5 g/day of SDR (SDR1.5). Daily feed intake and average daily gain of calves were not affected by feeding SDR as a feed additive. Cholesterol concentration was significantly affected by the 20th and 40th days of the experiment and decreased linearly by increasing SDR feeding level. Levels of liver enzymes, including aspartate aminotransferase and alanine aminotransferase, in the blood decreased by feeding SDR at day 40 of the experiment. Serum concentration of interleukin-6 at day 20 was not affected by dried rumen fluid feeding, whereas at day 40, a significant effect was observed among experimental treatments. The lowest value was recorded for SDR1.5 v. control calves. At day 20, the serum concentration of interferon-γ was influenced by supplementing SDR, and the highest value was recorded for SDR1.5 calves. The inclusion of SDR with 1% maltodextrin in suckling dairy calves had beneficial effects on the stimulation of calves' immune system.

Effects of dietary n-3 fatty acids and vitamin C on semen characteristics, lipid composition of sperm and blood metabolites in fat-tailed Moghani rams.

Sixteen fertile rams were randomly allotted to four groups and fed either of the four diets for 14 weeks: (1) control diet (COD) without fish oil (FO) and vitamin C (VC), (2) diet containing 2.5% FO (FOD), (3) diet containing 300 mg/kg DM VC (VCD), and (4) diet containing 2.5% FO and 300 mg/kg DM VC (FCD). Semen was collected at 14-d intervals from 1 April to 10 July (out of the physiologic breeding season in Iran). Semen volume and percentages of motile and progressively motile sperm were increased by FO and VC feeding. A significant interaction was also found between FOD and VCD on motility and progressive motility percentage (P<0.05). HOS-test and percentage of sperm with normal acrosome improved significantly by FO and VC. Rams fed FCD had better HOS-test and higher proportion of sperm with normal acrosome than rams in other groups (82.4 and 93.6%, respectively). Diets containing FO and FO and VC increased the proportion of docosahexaenoic acid in sperm (P<0.05). The activity of lactate dehydrogenase in the seminal fluid was significantly affected by VC and the interaction between FO and VC (P<0.05). Blood metabolites, except glucose, were affected positively by FO. The results showed that dietary supplementation with FO and VC improved seminal quality and may have beneficial effects on fertility in Moghani rams.