R. J. Hudson

Bio: R. J. Hudson is an academic researcher. The author has contributed to research in topics: Spotted deer & Dry matter. The author has an hindex of 2, co-authored 3 publications receiving 15 citations.

Voluntary Intake, Digestibility and Nitrogen Balance in Spotted Deer (Cervus nippon) Fed Forest By-product Silage, Oak Leaf Hay and Commercial Mixed Ration

Abstract: Forest by-product silage (FPS) comprised of foliage, shrubs, and wild grasses was prepared to examine feeding value as sole roughage source for spotted (sika) deer. This diet was compared with imported oak leaf hay (OLH) and a commercial mixed ration (CMR) in digestion balance trials with spotted deer. Dry matter intake was highest (p 0.05). Digestibility of dry matter was highest (p<0.05) for CMR. Digestibility of crude protein was highest in CMR and lowest in OLH and there were significant differences (p<0.05) among diets. Average daily gain, digestible dry matter intake and digestibility of crude fiber did not differ significantly among diets. Nitrogen intake, urinary and digestible nitrogen were highest (p<0.05) in CMR. However, nitrogen retention was not significantly different. Consequently, FPS is a good roughage source for deer having high digestibility, dry matter intake and availability of nitrogen.

A Study on the Seasonal Comparison of Dry Matter Intake, Digestibility, Nitrogen Balance and Feeding Behavior in Spotted Deer (Cervus nippon) Fed Forest By-products Silage and Corn Silage

Abstract: The purpose of this experiment was to assess seasonal variation of feed utilization by feed sources and to obtain information on the use of feed resources by comparing seasonal changes of dry matter intake, digestibility, nitrogen balance and feeding behavior in spotted deer (Cervus nippon) fed forest by-product silage (FBS) and corn silage (CS). Dry matter intake (DMI) of FBS was higher than that of CS in both winter and summer. While DMI of both diets was higher in summer, this was not significant at the 5% level. In contrast to DMI, digestible dry matter intake (DDMI) was higher for CS than for FBS in both seasons, but the difference was not significant. Digestibility of dry matter and crude protein was significantly higher (p 0.05) was found between the two seasons and diets for nitrogen intake (NI), 18.7 g/d in summer and 19.4 g/d in winter for FBS, 17.7 g/d in summer and 17.7 g/d in winter for CS. Fecal nitrogen was higher (p<0.01) for FBS than for CS and varied little seasonally. There was significant difference (p<0.01) between two seasons in urinary nitrogen, which was little difference between two diets. Retained nitrogen (RN) was different significantly (p<0.01) between two diets in both seasons, but there was little difference between seasons. Deer usually spent longer time on eating FBS than eating CS. Eating FBS took 221 min in summer and 187 min in winter, whereas eating CS took 113 min in summer and 109 min in winter. Deer spent less time on eating food in winter than in summer. Time spent on rumination was longer for FBS than for CS: for FBS, 504 min in summer and 456 min in winter, for CS, 423 min in summer and 279 min in winter. Time varied seasonally with both diets. (Asian-Aust. J. Anim. Sci. 2004. Vol 17, No. 1 : 80-85)

Influence of Berseem and Lucerne Silages on Feed Intake, Nutrient Digestibility and Milk Yield in Lactating Nili Buffaloes

Abstract: This study was conducted to evaluate feeding value of berseem and lucerne silage as a replacement for conventional fodder (berseem fodder) in lactating Nili buffaloes. Fifteen early lactating multi-parous Nili buffaloes, five buffaloes in each group were allotted three experimental diets. Berseem and lucerne fodders were ensiled at 30% DM (wheat straw was used to adjust the DM of fodders) with molasses (at the rate of 2% of fodder DM) in two bunker silos for 30 days. The diets contained 75% DM from berseem fodder (BF), 75% DM from berseem silage (BS) and 75% DM from lucerne silage (LS). Each diet contained 25% concentrate DM. Diets were mixed daily and fed twice a day at ad libitum intakes. Dry matter intake (DMI) was significantly higher (13.8 kg/d) in buffaloes fed BF diet than those fed LS (12.5 kg/d) and BS (11.9 kg/day) diets. The differences in digestible DMI and DMI as percent body weight were significant between fodder and silage based diets but non-significant when BS and LS were compared. Lower DMI with silage-based diets was probably because of low silage pH. Intake of NDF (NDFI) was higher (5.68 kg/d) in buffaloes fed BF diet followed by those fed LS (5.50 kg/d) and BS (5.00 kg/d) diets. The difference was significant (p<0.05) across fodder and silage based diets but NDFI was non-significant across both silage-based diets. The apparent DM digestibility was significantly different (p<0.05) between fodder and silage-based diets but was non-significant between LS and BS diets. Four percent fat corrected milk yield was significantly different (p<0.05) between fodder and silage-based diets but was non-significant between LS and BS diets. Higher milk yield with fodder based diet was because of more digestible nutrient intake (Table 3) compared with silage based diets. Milk CP, TP and NPN and SNF did not show any treatment effects. The present results indicated that the berseem and lucerne fodder ensiled at 30 %D M level with 2% molasses could safely replace (75% DM) the conventional leguminous fodder in the diets of lactating Nili buffaloes. (Asian-Aust. J. Anim. Sci. 2005. Vol 18, No. 4 : 475-478)

Effect of Additives and Fermentation Periods on Chemical Composition and In situ Digestion Kinetics of Mott Grass (Pennisetum purpureum) Silage

Abstract: This study was conducted to see the influence of additives and fermentation periods on Mott grass silage (MGS) characteristics, its chemical composition and to compare the digestion kinetics of Mott grass (MG) and MGS in Nili buffaloes. Mott grass chopped with a locally manufactured chopper was ensiled using two additives, cane molasses and crushed corn grains each at 2, 4 and 6% of forage DM for 30 and 40 days in laboratory silos. The pH, lactic acid concentration, dry matter (DM), crude protein and fiber fractions of MGS were not affected by the type or level of additive and fermentation periods. The non-significant pH lactic acid concentration, and chemical composition of MGS indicated that the both molasses and crushed corn were utilized at similar rate for the growth of lactic acid bacteria and production of organic acids. The MG ensiled with molasses at 2% of fodder DM for 30 days was screened out for in situ digestion kinetics in Nili buffaloes. Ruminal DM and neutral detergent fiber (NDF) degradabilities of MGS were significantly (p<0.05) higher than that of MG. The DM and NDF rate of degradation, lag time and extent of degradation was non-significant between MGS and MG. The higher ruminal degradation of DM and NDF of MGS than MG was probably a reflection of fermentation of MG during ensilation that improved its degradability by improving the availability of easily degradable structural polysaccharides to ruminal microbial population. The results in the present study have indicated that MG ensiled with either 2% molasses or 2% crushed corn for 30 days has better nutritive value for buffalo.

Urea kinetics in wethers exposed to different ambient temperatures at three dietary levels of crude protein

Abstract: Eighteen Suffolk wether lambs (BW = 24 kg) were chronically exposed to temperatures of cold (2°C) or warm (22°C). The experimental design consisted of a 2×3 factorial with a single crossover of environment treatment. The sheep were closely shorn and were housed in individual metabolic crates in controlled environment rooms. Sheep consumed pelleted diets ad libitum, which consisted of mainly barley grain and brome grass, and diets contained 7, 11 or 14% crude protein (CP). Animals were catheterized via one jugular vein with a PVC catheter and received a single injection of 60-65 Ci of ( 14 C)urea. Plasma urea-N (PUN), urinary urea (UU), and carbon specific radioactivity were measured. Urea metabolism was not affected by environment. Percent urea recycling and urea space clearance were highest (p<0.05) on the low nitrogen diet. Urea pool was increased (p<0.10) for the 14% CP diet. Both UU and PUN concentration were positively related (p<0.01) with diet CP content. Therefore, dietary CP content significantly influenced urea metabolism, however, cold exposure did not alter those parameters. (Asian-Aust. J. Anim. Sci. 2005. Vol 18, No. 6 : 795-801)

Silage from Agricultural By-products in Thailand: Processing and Storage

Abstract: Processing and storage of the silage from agricultural by-products were studied in two experiments. The first experiment was conducted to investigate the chemical composition and degradability of various silages with varying ensiling times. The experiment was a 5×3 factorial design, completely randomized, with factor A as the different formulated mixtures by varying level of urea addition (0, 0.5, 1.0, 1.5 and 2.0%) and factor B as the time of ensiling. Chemical composition changed little with time and varied only slightly with levels of urea in the mixtures. Dry matter (DM) degradability increased with increasing cassava levels while crude protein degradability and pH level increased with increasing urea addition. By using 'Flieg point', which relates to organic acid yields, there were no significant difference among ensiled mixtures and times of ensiling. Therefore it can be concluded that the 5th silage formulation is the most appropriate since its DM and crude protein (CP) degradability were highest. The second experiment was carried out to determine the quality of the 5th silage mixtures (from the previous trial) after being stored for up to 6 months. The experiment was a complete randomized design with samples taken at monthly intervals up to 6 months and subjected to laboratory and degradability analyses. The results showed no significant (p>0.05) difference in chemical composition except for increased neutral detergent fiber and acid detergent fiber percentage in association with increasing storage time. There were no significant (p>0.05) differences in 'Flieg point' among times of storage. In conclusion, this experiment showed that the silage from agricultural by-products can be stored for more than 6 months. (Asian-Aust. J. Anim. Sci. 2004. Vol 17, No. 4 : 473-478)