Two experiments were conducted to study the effects of variety and maturity stage on chemical composition and in vitro dry matter degradability of oat and barley forages. In exp1, four oat varieties and one barley var...Two experiments were conducted to study the effects of variety and maturity stage on chemical composition and in vitro dry matter degradability of oat and barley forages. In exp1, four oat varieties and one barley variety were harvested at three maturity stages: stage 1, Two weeks before stage 2; stage 2, Mid-dough for oat and early-dough for barley; stage 3, One week after stage 2. All samples were analyzed for DM, CP, ether extract, ash, ADF(acid detergent fiber), NDF(neutral detergent fiber), ADL(acid detergent lignin), NDICP(neutral detergent insoluble crude protein) and IVDMD(In vitro dry matter digestibility). There was no difference in chemical components and IVDMD among oat variety. But maturity stage had a profound influence on some nutrient contents and IVDMD. With maturity advancing, CP decreased from15.5% to 11.03% and from 14.7% to 10.9% at stage 1 and stage 2 for oat and for barley, respectively, and IVDMD decreased slowly from 72.0% to 64.9% and from 73.5% to 68.8% for oat and for barley, respectively. For fiber fractions, NDF declined before stage 2 and then level off after stage 2, while ADF changed little throughout maturation. The ADL trended to increase with increased maturity. The results from the present experiment revealed that Bailor has relatively greater IVDMD value and kept lower ADL content than any other cultivars. The observed variation in chemical composition and ruminal digestibility among various oat cultivars would allow breeders choose suitable oat forages for cattle diet. In experiment. 2, the DaisyⅡ incubator was used to compare IVDMD values of forages of seven oat cultivars using rumen fluid or faecal liquor as the inoculum source. There was a strong linear relationship between the two estimates (R 2 = 0.809; P < 0.001), which indicated that fecal liquor method has the potential to be used instead of rumen fluid for estimation of in vitro digestibility of forage. It is suggested the method for determination of IVDMD using faecal liquor was appropriate for batch operation with precision and efficiency.展开更多
The captive white-tailed deer industry has an estimated impact of 1.6 billion USD in the state of Texas alone. However, nutritional requirements for cervids are determined through research based on sheep and goats. Th...The captive white-tailed deer industry has an estimated impact of 1.6 billion USD in the state of Texas alone. However, nutritional requirements for cervids are determined through research based on sheep and goats. The objective of this study was to determine the effects of zinc on differences in dry matter digestibility in vitro for white-tailed does (Odocoileus virginianus). Deer (n = 2) were ethically harvested, rumens were collected, and placed into a cooler containing warm water. Rumen contents were agitated, and fluid was filtered using cheese cloth while applying CO2. Fluid was placed into four separate incubator jars with filter bags containing a 1:1 alfalfa to coastal hay blend. Zinc doses of 0.073 mg/kg/d equivalents were added to two of the jars ( Zn), and the additional two jars received 0.00 mg/kg/d (CON). Following 48 h of incubation, in vitro true digestibility (IVTD) showed no significant differences between the control and the treatment groups. Average dry matter digested in vitro was 91.87% and 95.13%, respectively. There were no differences detected in ADF, NDF, IVTD, or OM between the treatment groups. While no detectable differences were observed in this study, this methodology did prove to be viable and functional for microbial digestion in vitro. This study can be replicated with multiple experimental units to confirm the observations of increased digestibility. Formal nutritional guidelines can be created to allow for more efficient feeding of cervids thereby reducing feed costs and continuing the growth of the captive deer industry.展开更多
文摘Two experiments were conducted to study the effects of variety and maturity stage on chemical composition and in vitro dry matter degradability of oat and barley forages. In exp1, four oat varieties and one barley variety were harvested at three maturity stages: stage 1, Two weeks before stage 2; stage 2, Mid-dough for oat and early-dough for barley; stage 3, One week after stage 2. All samples were analyzed for DM, CP, ether extract, ash, ADF(acid detergent fiber), NDF(neutral detergent fiber), ADL(acid detergent lignin), NDICP(neutral detergent insoluble crude protein) and IVDMD(In vitro dry matter digestibility). There was no difference in chemical components and IVDMD among oat variety. But maturity stage had a profound influence on some nutrient contents and IVDMD. With maturity advancing, CP decreased from15.5% to 11.03% and from 14.7% to 10.9% at stage 1 and stage 2 for oat and for barley, respectively, and IVDMD decreased slowly from 72.0% to 64.9% and from 73.5% to 68.8% for oat and for barley, respectively. For fiber fractions, NDF declined before stage 2 and then level off after stage 2, while ADF changed little throughout maturation. The ADL trended to increase with increased maturity. The results from the present experiment revealed that Bailor has relatively greater IVDMD value and kept lower ADL content than any other cultivars. The observed variation in chemical composition and ruminal digestibility among various oat cultivars would allow breeders choose suitable oat forages for cattle diet. In experiment. 2, the DaisyⅡ incubator was used to compare IVDMD values of forages of seven oat cultivars using rumen fluid or faecal liquor as the inoculum source. There was a strong linear relationship between the two estimates (R 2 = 0.809; P < 0.001), which indicated that fecal liquor method has the potential to be used instead of rumen fluid for estimation of in vitro digestibility of forage. It is suggested the method for determination of IVDMD using faecal liquor was appropriate for batch operation with precision and efficiency.
文摘The captive white-tailed deer industry has an estimated impact of 1.6 billion USD in the state of Texas alone. However, nutritional requirements for cervids are determined through research based on sheep and goats. The objective of this study was to determine the effects of zinc on differences in dry matter digestibility in vitro for white-tailed does (Odocoileus virginianus). Deer (n = 2) were ethically harvested, rumens were collected, and placed into a cooler containing warm water. Rumen contents were agitated, and fluid was filtered using cheese cloth while applying CO2. Fluid was placed into four separate incubator jars with filter bags containing a 1:1 alfalfa to coastal hay blend. Zinc doses of 0.073 mg/kg/d equivalents were added to two of the jars ( Zn), and the additional two jars received 0.00 mg/kg/d (CON). Following 48 h of incubation, in vitro true digestibility (IVTD) showed no significant differences between the control and the treatment groups. Average dry matter digested in vitro was 91.87% and 95.13%, respectively. There were no differences detected in ADF, NDF, IVTD, or OM between the treatment groups. While no detectable differences were observed in this study, this methodology did prove to be viable and functional for microbial digestion in vitro. This study can be replicated with multiple experimental units to confirm the observations of increased digestibility. Formal nutritional guidelines can be created to allow for more efficient feeding of cervids thereby reducing feed costs and continuing the growth of the captive deer industry.
