• Asian-Australasian Journal of Animal Sciences
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• v.20 no.1
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• pp.60-69
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• 2007

Ruminants eating dry forage secrete large volumes of saliva which results in decreased plasma volume (hypovolemia) and the loss of $NaHCO_3$ from the blood. The present research investigated whether or not hypovolemia and the loss of $NaHCO_3$ from the blood in goats brought about by dry forage feeding actually depresses feed intake and saliva secretion, respectively. The present experiment consisted of three treatments (NI, ASI, MI). In the control treatment (NI), a solution was not infused. In the ASI treatment, i.v. infusion of artificial parotid saliva was initiated 1 h before feeding and continued for the entire 2 h feeding period. In the MI treatment, iso-osmotic mannitol solution was infused. The NI treatment showed that hematocrit and plasma total protein concentration were increased due to decreased circulating plasma volume brought about by feeding. In the ASI treatment, the fluid and $NaHCO_3$ that were lost from the blood because of a feeding-induced acceleration of saliva secretion was replenished with an intravenous infusion of artificial parotid saliva. This replenishment lessened the levels of suppression on both feeding and parotid saliva secretion. When only the lost fluid was replenished with an intravenous infusion of iso-osmotic mannitol solution in the MI treatment, the degree of feeding suppression was lessened but the level of saliva secretion suppression was not affected. These results indicate that the marked suppression of feed intake during the initial stages of dry forage feeding was caused by a feeding-induced hypovolemia while the suppression of saliva secretion was brought about by the loss of $NaHCO_3$ from the blood due to increased saliva secretion during the initial stages of feeding.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.3
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• pp.366-370
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• 2002

The objective of this study was to examine whether feeding induced hypovolemia (decrease in plasma volume) acts on the regulation of feed intake in goats fed on dry forage. In order to prevent feeding induced hypovolemia, a 2 h intravenous infusion (16-18 ml/min) of isotonic mannitol solution was begun 1 h prior to feeding and continued until 1 h after the start of the 2 h feeding period. The intravenous infusion of isotonic mannitol solution (MI) decreased plasma osmolality by 1.0%, plasma total protein concentration by 4.2% and hematocrit by 5.9%, respectively. In comparison with no infusion (NI), MI significantly decreased thirst level by approximately 13%. At the completion of the 2 h feeding period, cumulative feed intake had been increased by 43% by MI. In conclusion, feeding induced hypovolemia in goats fed on dry forage increased thirst level more than the increase in plasma osmolality did. The results demonstrate that feeding induced hypovolemia is one of the factors controlling feed intake in goats fed on dry forage.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.3
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• pp.230-234
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• 1996

This study was conducted to compare the intake, digestibility and utilization of nitrogen by goats consuming high and low tannin diets. Low tannin diets were 100% grass(GS) and 50% grass + SO% alfalfa (GA), and high tannin diets were 50% grass + 50% lespedeza(GL) and 50% grass + 50% oak browse(G0). Dry matter intake did not differ among all diets, but digestibility of dry matter, cellular constituents, NDF and ADF showed slightly lower for high tannin diets(GO) than low tannin diets(GS and GA), but those were not differ between GL and low tannin diets with the exception of ADF digestibility. Total faces and urinary N were lower for high tannin diets than for low tannin diets. Apparently digested N was high in GA diets, but low in GO diets(P

• Asian-Australasian Journal of Animal Sciences
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• v.8 no.2
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• pp.107-111
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• 1995

An experiment was conducted at Pabna milkshed area under Bathan condition during November, 1992 to February 1993 with 16 milking cows fed legume forage with straw supplementation (treated group) and 8 milking cows fed legume forage only (control group). From the study, the results revealed that supplementation of straw with leguminous diet increases the total dry matter intake (DMI) of 11.83 kg/d/cow for the treated group and 11.53 kg/d/cow for the control group. The average daily legume forage intake was $37.39{\pm}8.67kg/d/cow$ and $49.62{\pm}10.57kg/d/cow$ for the treated and control group respectively and the difference was significant (p < 0.05). The results also exhibited that due to the supplementation of straw, the legume forage intake reduced by 12 kg/d/cow. The forage dry matter intake (DMI) kg/d/cow for the treated and control groups were $6.18{\pm}1.44kg$ and $8.38{\pm}1.95kg$ respectively. The milk production was $8.64{\pm}1.15litre/day$ for the treated group which was significantly (p < 0.05) higher than the control group ($7.74{\pm}1.24litre/day$). The average initial body weight of the supplemented and control groups were $338.06{\pm}39.32kg$ and $329.87{\pm}48.03kg$ respectively. Whereas, the final body weight of supplemented group was $344.33{\pm}35.90kg$ and control group was $330.35{\pm}37.28kg$. It may be concluded that straw supplementation with legumes diet could save legume forage for further use as well as increase milk production.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.8
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• pp.1126-1130
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• 2003

The conditions of measurement for the determination of bulk density were evaluated to assess the bulkiness of 8 kinds of forage. The bulkiness of the forages was determined with 4 different sizes of forage samples with 7 different pressure application under air-dry and wet conditions. The dry bulk density (DBD) curvilinearly regressed with the pressure applied. The particle size of the samples and kinds of forage used in the present study did not affect changes in values of DBD determined under pressures over $20g/cm^2$ up to $200g/cm^2$. The values of the wet bulk density (WBD) increased as an increment of particle size, but were not always regressed on the particle size of the 8 kinds of forage. The DBD determined on 8 mm particles showed a higher correlation coefficient with neutral detergent fiber (NDF) contents. The DBD may be a useful tool for the assessment of NDF in forage, when it is determined under condition of a pressure of $100g/cm^2$ or over with a particle size of 8 mm. The WBD may not be utilized for the direct measurement of the physical characteristics of forage, but may be required a thorough consideration on water solubility of forages. Further studies are needed to clarify the DBD contribution to the prediction of forage intake by ruminants.

• Asian-Australasian Journal of Animal Sciences
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• v.20 no.8
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• pp.1182-1189
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• 2007

An intracerebroventricular (ICV) infusion of somatostatin 1-28 (SRIF) was used as a thirst-controlling peptide antagonist to investigate whether or not thirst-controlling peptides are involved in the significant decrease in feed intake during the initial stages of feeding large-type goats on dry forage. A continuous ICV infusion of SRIF was conducted at a small dose of $4{\mu}g$ ml/h for 27 h from day 1 to day 2. Goats (n = 5) were fed roughly crushed alfalfa hay cubes for 2 h twice daily and water was given ad libitum. Feed intake was measured during ICV infusion of artificial cerebrospinal fluid (ACSF) and SRIF. The feed intake during SRIF infusion increased significantly compared to that during ACSF infusion. In comparison to the ACSF treatment, plasma osmolality during the SRIF treatment significantly decreased during the first half of the 2 h feeding period. The factor causing the decrease in plasma osmolality during the ICV infusion of SRIF was a decrease in plasma Na, K, Cl, and Mg concentrations. In comparison to the ACSF infusion treatment, parotid saliva secretion volumes during the 2 h feeding period in the SRIF infusion treatment were significantly larger. While there was no significant difference in cumulative water intake (thirst levels) between the SRIF and the ACSF treatments upon conclusion of the 2 h feeding period, based on the plasma osmolality results it is thought that thirst level increases brought about by alfalfa hay cube feeding in the first half of the feeding period were reduced. It is thought that the somatostatin-induced increases in feed intake during the 2 h feeding period in the present experiment were caused by decreases in plasma osmolality brought about by the somatostatin infusion. As a result, it is suggested that the significant decrease in feed intake during the initial stages of feeding in large-type goats given roughly crushed alfalfa hay cubes, was due to the actions of thirst-controlling peptides.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.9
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• pp.1297-1302
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• 2003

To determine whether the feeding of different species of hay affects the dry-matter intake and the serum cortisol level of sheep, 6 non-pregnant, non-lactating ewes were offered alfalfa (Medicago sativa) hay (Al), oats (Avena sativa) hay (Ot) and perennial ryegrass (Lolium perenne) hay (Pr) under 6 kinds of treatment including 1) change from Al to Ot, 2) Al to Pr, 3) Ot to Al, 4) Ot to Pr, 5) Pr to Al, and 6) Pr to Ot. The experimental design was a 6${\times}$6 Latin square with a 14 day period of which 9 days were a preliminary period and 5 days as a digestion trial period. The change in hay feeding was done abruptly on the first day of each period without an adaptation period. The blood from the jugular vein was collected on the first, third and the last day of each period through a sterile catheter for the analysis of cortisol. The dry-matter intake was recorded daily throughout the period. The mean daily intake of dry matter (DM, g/kg live weight) was significantly different among the 3 species of hay (Al>Ot>Pr; p<0.05). The digestibility of DM for Al and Ot was the same, but that for Pr was significantly lower than Al and Ot (p<0.05). The mean serum cortisol levels were significantly different among the hays (p<0.05). The level for Pr was the highest and that for Al was the lowest. The abrupt change of hay feeding of 6 treatments produced a significant change in the serum cortisol levels. The DM intake was inversely related to the change of the cortisol level. It is suggested that the animal' intake response to different species of hay may be partly motivated by the psychological feelings toward the hay offered.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.4
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• pp.399-406
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• 1997

This research was carried out to investigate the effect of zeranol injection on dry matter(DM) and nutrient intake requirement by growth stage of early castrated bull with 3 treatments(bul1, steer, steer+zeranol) with 28 Holstein bull at National Livestock Research Institute. The main results were as follows: DM intake at growing and fatting stage was the highest in steer groups, that the highest in bull groups at finishing stage and overall mean DM intake was 5% lower at steer+zeranol groups compared to bull and steer, respectively. Net energy intake at finishing stage was the highest as 35.49 Mcal at bull groups, while overall mean net energy intake was 101 - 109% of NRC requirement without significant difference. Concentrate intake to body weight was 1.68- 1.82, 1.91 -2.08 and 1.81 -2.05% at growing, fatting and finishing stage, respectively. Overall mean concentrate intake to body weight at steer groups was 1.94%, which is 1.8 and 1.81% higher compared to bull and steer+zeranol groups, respectively. Feed conversion ratio(DM) during overall period was the worst at steer groups as 9.321g, and also net energy conversion ratio was similar to DM conversion ratio.

• Journal of The Korean Society of Grassland and Forage Science
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• v.16 no.3
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• pp.245-252
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• 1996

This experiment was carried out to investigate the effect of feeding order bay-concentrate-silage, concentratehay- silage, silage-concentrate-hay, silage-concentrate-hay, concentrate-silage-hay) on ruminal characteristics change with 3 fistulated dry Holstein cows in a Latin square design. The main results obtained were as follows : DM intake in forage hayconcentrate-silage feeding order was 1.65% of body weight, which is the highest of all treatments, but that in concentrate-hay-silage 1.4%, which is the lowest. The difference between max and min rumen pH in hayconcentrate-silage feeding order was lowest as 0.55, but there is no significant. The mean rumen $NH_3N$ content in silage-concentrate-hay feeding order was highest as 6.12mg/100ml, but that in silageconcentrate-hay feeding order lowest as 4.82mg/100ml. Acetic acid and propionic acid content was highest in forage hay-concentrate-silage feeding order. but there is no significant. The ratio of acetic acid to propionic acid averaged 3.47~3.69(NS). In conclusion, the best feeding order fitted in ruminal physiology was forage hay-concentrate-silage.

• Journal of The Korean Society of Grassland and Forage Science
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• v.17 no.1
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• pp.82-88
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• 1997

A study was carried out to evaluate the values of roughages available in Korea on feed intake and digestibility of Korean native goats and consequently to apply its results to the feeding system of Korean goats as a basic information. The results are as follows. 1. The protein contents in Alfalfa and Acacia leaf were 17.6 and 16.3% respectively 11.7 and 6.8% higher than orchardgrass and pine needle. Ether extract tom pine needle was about two times higher than other roughage sources which are 9.2%. 2. Dry matter intake per day in goats fed alfalfa, acacia leaf and orchardgrass was higher (P < 0.05) at 590.3, 543.8 and 496.58 respectively and 217.lg in pine needle. 3. Dry matter intake per basal weight (DM glkg of B$W^{0.75}$ and DM g/kg of BW%) was higher in goats fed acacia leaf at 68.5 and 3.5% respectively than any other treatments goats fed pine needle showed the lowest (P< 0.05) dry matter intake at 28.6 and 1.5% respectively. 4. Dry matter digestibility was highest (PcO.05) in alfalfa fed goats at 61.4%. Dry matter digestibilities in orchardgrass, pine needle and acacia leaf were 58.0, 46.8 and 46.6% respectively. 5. Total digestible nutrients were highest (P< 0.05) in Alfalfa fed goats at 59.5%. Total digestible nutrients in orchardgrass, pine needle and acacia leaf were 54.2, 50.7 and 47.7% respectively. 6. In conclusion, the value of orchardgrass as feed for goats was as excellent as alfalfa and although acacia leaf had a less value than alfalfa in goats, it is considered to be used as a protein supplement in diets for goats due to its high content of protein and excellent palatability. Intake of pine needle in Korean goats in this study was satisfactory and it indicates the possibility of its use as a supplement in diets for goats. However, fkther investigation will be necessary particularly on the deleterious effects of ether extracts of pine needle