Hakan Biricik

Effects of synchronizing starch and protein degradation in rumen on fermentation, nutrient utilization and total tract digestibility in sheep

Abstract The objective of this experiment was to investigate the effects of synchronizing the dietary starch and crude protein (CP) degradation in the rumen on nutrient utilization, fermentation, and total tract digestibility in sheep. The four diets were formulated with different rates of starch and CP release in the rumen but with similar metabolic energy, starch, and CP. The diets were slowly degradable starch, slowly degradable protein; slowly degradable starch, rapidly degradable protein; rapidly degradable starch, rapidly degradable protein; and rapidly degradable starch, slowly degradable protein. The diets were fed to four cannulated sheep ad libitum in two equal portions, using a 4x4 Latin square design. Dry matter intake (DM) was not influenced by either the rate of starch or protein degradation. There was no significant effect of dietary treatment on the digestibility of DM, organic matter, starch, CP, neutral detergent fiber or acid detergent fiber in the rumen and total tract. Ruminal pH was greater for sheep fed slowly degradable starch diets than rapidly degradable starch (P< 0.05). Ruminal total volatile fatty acid concentrations were not affected by treatments but the molar proportions of propionic acid were greater for sheep fed rapidly degradable starch diets than slowly degradable starch diets (P< 0.05). The ratios of acetic acid (A) to propionic acid (P) were higher for sheep fed slowly degradable starch diets than rapidly degradable starch diets (P< 0.05). Ruminal ammonia-N concentrations were not affected from the degradability characteristics of protein. Rumen pH and A:P were higher in diets containing slowly degradable starch than in diets rapidly degradable starch. Propionic acid was higher in diets containing rapidly degradable starch than in diets containing slowly degradable starch. Rumen fermentation and utilization of nutrients in the rumen affected starch degradability more than protein degradability. Synchronizing starch and protein degradation in rumen had no effect on the intake, digestibility of nutrients in sheep.

The effect of dry corn gluten feed on chewing activities and rumen parameters in lactating dairy cows

Abstract The objectives of this research were to evaluate the effects of increasing levels of dry corn gluten feed (DCGF) on dry matter intake (DMI), chewing activity, and rumen fermentation when used to replace a portion of corn silage in diets for lactating Holstein cows. Eight lactating Holstein primiparous cows averaging 98±20 d in milk and weighing 515±20 kg were randomly assigned in a 4x4 Latin square design with 4 week periods. Dietary treatments were 1) a control diets (C) of 50% forage (corn silage and wheat straw, 35%, 15% DM basis, respectively), 2) a low DCGF diet (L-DCGF) in which 10% of the same corn silage was replaced by DCGF, 3) a medium DCGF diet (M-DCGF) in which 18% of the same corn silage was replaced by DCGF, and 4) a high DCGF diet (H-DCGF) in which 25% of the same corn silage was replaced by DCGF. The proportion of particles retained on the 19.0 mm screen and physical effectiveness factor of the H-DCGF was lower (P<0.05) than in the other groups. Increasing the level of DCGF did not change DMI. Cows fed the C diet spent significantly more time ruminating and chewing per day compared with the M-DCGF and H-DCGF diets (483.88, 435.63, 431.25 min/d, P<0.05; and 818.38, 753.00, 745.75 min/d respectively, P<0.05). Cows fed the C diet had ruminal pH values higher than the cows fed the M-DCGF and H-DCGF diets (6.02, 5.95, and 5.91, P<0.05). The total volatile fatty acid and propionate levels of H-DCGF fed cows were higher than the control (P<0.05). The changes in acetate (A) and propionate (P) concentrations resulted in a decrease in A/P ratio, when corn silage was replaced by DCGF, which led to a reduction in the particle size of the diets (P<0.05). It was concluded that when ratio 18 and 25% DCGF were substituted for corn silage, rumination time, chewing activities and ruminal pH are negatively affected. The optimum level for the addition of DCGF was found to be below 18% of the diet for a healthy rumen and a chewing behaviour in dairy cows.

Effects of supplemental humic acid on ruminal fermentation and blood variables in rams

In this study, we particularly aimed to research the effect of supplemental humic acid on ruminal fermentation and blood variables in rams. A trial was conducted to evaluate the effect of humic acid (HA) on protozoa count, percentages of different protozoa types and blood parameters. Three male Kivircik rams with ruminal cannula were used in a Latin square design, during 22 days periods (15 days for adaptation, 7 days for collection). They received 0 control group (CG), 5 g/day or 10 g/day of HA (HA5, HA10, assay groups). HA were added to the ration with grain diet. Ration was consisted of 5% grain diet and 95% alfalfa hay. Rumen contents collected before and, 3h and 6h after morning feeding on days 1 and 7 in each collection period were analyzed. Blood samples were also collected the same days. No significant difference in biochemical and hematological parameters (except eosinophils levels, P<0.05), variables of ruminal fluid (except sodium levels before feeding) and species of rumen protozoa organism (except the percentage Epidinium spp.) were evidenced with the addition of HA. In conclusion, we think that they might have been true the widely use in animal food of humates which don’t have any negative effect on biochemical and hematological parameters in particular.

The effect of partial replacement of corn silage on rumen degradability, milk production and composition in lactating primiparous dairy cows

Abstract The objective of this experiment was to evaluate the effects of partial replacement of corn silage with long alfalfa hay and/or coarse chopped wheat straw on neutral detergent fibre (NDF) rumen degradability, milk yield and composition in late lactating dairy cows fed diets with 50% forage on dry matter basis. Twelve late lactating Holstein primiparous cows including four cows equipped with a rumen cannula, averaging 210 ± 20 d in milk and weighing 575 ± 50 kg were randomly assigned in a 4x4 Latin square design. During each of four 21-d periods, cows were fed 4 total mixed diets that were varied in the forage sources: 1) 50% corn silage (CS), 2) 35% corn silage + 15% wheat straw (CSW), 3) 35% corn silage + 15% alfalfa hay (CSA), 4) 25% corn silage + 10% wheat straw + 15% alfalfa hay (CSWA). The production of milk averaged 18.55, 20.41 and 20.06 kg/d for unadjusted milk production, 4% fat corrected milk and solid corrected milk, respectively, and was not affected by treatments. Likewise, milk composition or production of milk components was not affected by diets and averaged 4.69% fat, 3.66% protein, 4.51% lactose, 866 g/d fat, 665 g/d protein, 824 g/d lactose. Treatments had no effect on in situ NDF soluble, degradable and potential degradability of all diets, whereas the effective degradability (ED) of NDF was greater for cows fed CS diet than for cows fed CSW, CSA and CSWA diets (P<0.05). These values suggested that the partial replacement of corn silage with alfalfa hay and/or wheat straw has no unfavourable effect on the productive parameters.