• Asian-Australasian Journal of Animal Sciences
• /
• v.28 no.6
• /
• pp.796-806
• /
• 2015

To evaluate the effects of feeding linseed oil or/and sunflower oil mixed with fish oil on milk yield, milk composition and fatty acid (FA) profiles of dairy cows fed a high-concentrate diet, 24 crossbred primiparous lactating dairy cows in early lactation were assigned to a completely randomized design experiment. All cows were fed a high-concentrate basal diet and 0.38 kg dry matter (DM) molasses per day. Treatments were composed of a basal diet without oil supplement (Control), or diets of (DM basis) 3% linseed and fish oils (1:1, w/w, LSO-FO), or 3% sunflower and fish oils (1:1, w/w, SFO-FO), or 3% mixture (1:1:1, w/w) of linseed, sunflower, and fish oils (MIX-O). The animals fed SFO-FO had a 13.12% decrease in total dry matter intake compared with the control diet (p<0.05). No significant change was detected for milk yield; however, the animals fed the diet supplemented with SFO-FO showed a depressed milk fat yield and concentration by 35.42% and 27.20%, respectively, compared to those fed the control diet (p<0.05). Milk c9, t11-conjugated linoleic acid (CLA) proportion increased by 198.11% in the LSO-FO group relative to the control group (p<0.01). Milk C18:3n-3 (ALA) proportion was enhanced by 227.27% supplementing with LSO-FO relative to the control group (p<0.01). The proportions of milk docosahexaenoic acid (DHA) were significantly increased (p<0.01) in the cows fed LSO-FO (0.38%) and MIX-O (0.23%) compared to the control group (0.01%). Dietary inclusion of LSO-FO mainly increased milk c9, t11-CLA, ALA, DHA, and n-3 polyunsaturated fatty acids (PUFA), whereas feeding MIX-O improved preformed FA and unsaturated fatty acids (UFA). While the lowest n-6/n-3 ratio was found in the LSO-FO, the decreased atherogenecity index (AI) and thrombogenicity index (TI) seemed to be more extent in the MIX-O. Therefore, to maximize milk c9, t11-CLA, ALA, DHA, and n-3 PUFA and to minimize milk n-6/n-3 ratio, AI and TI, an ideal supplement would appear to be either LSO-FO or MIX-O.

• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.8
• /
• pp.1266-1271
• /
• 2007

This study examined effects of calcium supplemented milk on bone loss in ovariectomized rats. Twenty four Sprague-Dawley female rats, 7 weeks-old, were divided into 4 groups, ovariectomized and fed diets containing: 1) control, no Ca supplemented milk, 2) ovx 1, Ca carbonate supplemented milk, 3) ovx 2, ionized Ca supplemented milk, and 4) ovx 3, nano Ca supplemented milk. All rats were fed 1 ml of milk containing 20 mg supplemented Ca. After 18 wk feeding, body weight gain and food efficiency ratio were significantly different between ovx 1 and ovx 3. Serum concentration of calcium and phosphorus were not different among groups. However, there was a significant difference in calcium content of dry femoral weight in ovx 3 compared with the control and ovx 2. In addition, femoral bone mineral density ($g/cm^2$) was significantly greater in ovx 3 than in other groups (p<0.05). The ovx 3 group showed the highest stiffness (N/mm), maximum energy (N) in femur and trabecular bone area (%). The present study indicated that nano Ca supplementation in milk may be an effective way to enhance bone calcium metabolism for ovariectomized rats.

• Journal of Veterinary Clinics
• /
• v.19 no.2
• /
• pp.228-235
• /
• 2002

Mastitis is the most costly disease results in lost milk production, decreased milk quality, milk discard, early culling of cows, drug costs and labor costs in dairy cow. Until now, a antibiotic administration at the end of lactation, dry cow therapy has been known the most effective and widely used mastitis control method. However, dry cow therapy do not control a new infection in the late dry and prepartum period because dry cow products have only persistent activity in the early dry period. Therefore, this study was conducted to evaluate clinical effect of sustained released biodegradable cephalexin microsphere using PLGA in bovine mastitis control during dry period. PLGA has been approved as controlled drug release system because of non-toxic, non-tissue reactive and bioerodible characteristics. This study revealed that cephalexin microsphere had a spherical shape with characteristic porous structure on the surface. Also, in vitro drug release studies are clearly observed that the release rate of cephalexin from PLGA microsphere decrease during the first 21 days after initial burst and then increase again between 3 and 4 weeks showing pulsatile releasing pattern. On the other hand, as tried in field the new infection rate, cure rate and mean SCC after parturition in cephalexin microsphere infused group were significantly differenced as compared to the control group. Accordingly, a sustained release of cephalexin from a biodegradable microsphere could make dry cow therapy more efficiently by preventing a new infection and decreasing the number of existing infection of mammary gland during dry period.

• Asian-Australasian Journal of Animal Sciences
• /
• v.13 no.4
• /
• pp.474-477
• /
• 2000

Two experiments were conducted to study the use of urea-treated rice straw (UTRS) and whole sugar cane (WSC) crop as roughage sources for dairy cattle during the dry season. Experiment I, four rumen-fistulated dairy crossbred steers were assigned to receive roughage treatments according to a $4{\times}4$ Latin square design: $T_1=urea-treated$ (5%) rice straw, $T_2=UTRS$ and WSC at 75:25% DM, $T_3=UTRS$ and WSC at 25:75% DM, and $T_4=WSC$. Experiment II, three rumen fistulated, late lactating multiparous Holstein-Friesian crossbreds were randomly allotted to a $3{\times}3$ Latin square design to receive three types of roughages; $T_1=WSC$, $T_2=UTRS$, $T_3=WSC+UTRS$ at 50:50% DM. It was found that combination of UTRS and WSC at 75:25 ratio significantly increased DM intake while intake of WSC alone was lowest. Moreover, inclusion of UTRS into WSC enhanced digestibilites (Exp. I). In Exp. II, combination of UTRS with WSC at 50:50 ratio (DM) enhanced DM intake (kg/d) (p<0.05) and especially milk yield, milk fat and protein percentages. The findings suggest the combined use of WSC and UTRS improved the feeding values of these roughages for dairy cattle during the dry season.

• Animal Bioscience
• /
• v.34 no.10
• /
• pp.1600-1606
• /
• 2021

Objective: This study was conducted to enhance our understanding of nitrogen (N) metabolism and mammary amino acid (AA) utilization in lactating cows with divergent phenotypes of residual feed intake (RFI). Methods: Fifty-three multiparous mid-lactation Holstein dairy cows were selected for RFI measurements over a 50-d experimental period. The 26 cows with the most extreme RFI values were classified into the high RFI (n = 13) and low RFI (n = 13) groups, respectively, for analysis of N metabolism and AA utilization. Results: Compared with the high RFI cows, the low RFI animals had lower dry matter intake (p<0.01) with no difference observed in milk yield between the two groups (p>0.10). However, higher ratios of milk yield to dry matter intake (p<0.01) were found in the low RFI cows than in the high RFI cows. The low RFI cows had significant greater ratios of milk protein to metabolizable protein (p = 0.02) and milk protein to crude protein intake than the high RFI cows (p = 0.01). The arterial concentration and mammary uptake of essential AA (p<0.10), branched-chain AA (p<0.10), and total AA (p<0.10) tended to be lower in the low RFI cows. Additionally, the low RFI cows tended to have a lower ratio of AA uptake to milk output for essential AA (p = 0.08), branched-chain AA (p = 0.07) and total AA (p = 0.09) than the high RFI cows. Conclusion: In summary, both utilization of metabolizable protein for milk protein and mammary AA utilization are more efficient in cows with lower RFI than in the high RFI cows. Our results provide new insight into the protein metabolic processes (related to N and AA) involved in feed efficiency.

• Asian-Australasian Journal of Animal Sciences
• /
• v.30 no.12
• /
• pp.1711-1717
• /
• 2017

Objective: This experiment was studied the effects of various levels of crude glycerin (CG) in dairy goat diet on daily intake, milk yield, milk composition, some physical properties and some quality changes of goat milk after sterilization. Methods: Twelve 75% Saanen dairy goats (body weight = $49{\pm}3kg$; days in milk = $60{\pm}12d$) were randomly assigned in a completely randomized design to evaluate the effects of three experimental diets consisting of 0%, 5%, and 10% CG (dry matter basis) which were formulated to meet or exceed the nutrient requirements of goats. Experimental dairy goats were evaluated for feed and milk yield. Milk samples were analyzed for their composition, including fatty acids, casein profile, fat globule size, and color, and were sterilized to evaluate milk heat stability. Results: There were no significant differences between 0% and 5% CG treatments infeed. Increasing CG supplementation from 0% to 5% increased milk yield from $2.38{\pm}0.12$ to $2.64{\pm}0.23kg/goat/d$. In addition, milk samples from 5% CG treatment had the highest total solids, fat content and lactose content, and largest fat globule size. Increasing CG to 10% resulted in a decrease in milk fat. After sterilizing at $116^{\circ}C$, $F_0=3min$, goat milk samples from 5% CG treatment had slightly higher sediment content and comparatively higher degree of browning. Conclusion: Considering milk yield, milk fat content and quality of sterilized milk, 5% CG supplementation in a total mixed ration has a potential for implementation in dairy goats.

• Journal of Animal Science and Technology
• /
• v.51 no.1
• /
• pp.33-38
• /
• 2009

Effects of dry matter intake restriction to the level of recommend by NRC (2001) on intake balance of dry matter and nutrients in Holstein lactating cow were evaluated. 24 lactating cows were divided into two groups and individually fed one of the TMR offered as ad libitum (control) and restricted amount (treatment) as recommended by NRC (2001). Milk yield including 4% FCM and FPCM were showed higher tendency in treatment group then those of control group. Also, intakes of dry matter, net energy and metabolizable protein were tended to be higher in treatment group then control group. Actual dry matter and net energy intakes in control group were higher (p<0.001) then those of recommended amount by NRC (2001), whereas no significant differences in treatment group. The estimated $NE_L$ allowable milk yield were lower (p<0.001) in both control and treatment group than those of recommended by NRC (2001). It was concluded that to allow ad libitum feeding of diet containing high levels of concentrate to the lactating cows might decrease the efficiency of feed nutrients and hence result in no positive effect on productivity of milk.

• Journal of The Korean Society of Grassland and Forage Science
• /
• v.15 no.1
• /
• pp.61-66
• /
• 1995

This experiment was conducted to evaluate the effect of the various stage of growth on dry matter yield and chmical composition of forage oat(Avena sativa. L.). Seeds were planted on March 13 1993 on the Livestock Experimental Farm Keiymung junior college at keongsan Keongsangbukdo. Oat plant were harvested at various stages of maturity while the oat was in the premature stages. 1. Whole plant dry matter increased with advancing maturity. It was 11.8, 12.3, 14.9, 25.6 and 28.8% at before flag leaf emerged, flag leaf emerged, heads emerged, milk and dough stage., respectively. Dry matter increased very little during from before flag leaf emerged to heads emerged, after which it increased rapidly until the plant was dough stage. 2. Leaf weight ratio decreased with advancing maturity from before flag leaf emerged to dough, varied fmm 58 to 1 1%. Grain(with lemma, palea) increased with advancing maturity from heads emerged to dough, varied from 7 to 43%. 3. The content of cmde protein decreased during the stages of growth until milk(P<.OS), and then changed very little with advancing maturity. 4. The content of NDF and ADF increased rapidly during the early growth period until heading(P<.05) and then decreased due to the increase in carbohydrate storage in the grain. 5. The dry matter yields per ha increased with advancing maturity, it was 2,420, 4,380, 7,190, 13,130 and 14,530kg at before flag leaf emerged, flag leaf emerged, heads emerged, milk and early dough, respectively. Significant difference has been obtained among stages of growth(P< .05). 6. According to the results obtained from this study, it is suggested that milk stage of maturity is higher in dry matter yields would be recomendable for spring oat for silage.

• Asian-Australasian Journal of Animal Sciences
• /
• v.14 no.10
• /
• pp.1400-1404
• /
• 2001

$Holstein\;{\times}\;indigenous$ multiparous dairy cows were offered diets with increasing roughage neutral detergent fiber (NDF) contents to determine the effects on intake, milk yield and compositions. Roughage NDF contents were 15, 18, 21 and 24% dry matter (DM), and concentrate NDF content was 10% DM. Experimental treatments were isonitrogenous and isocaloric diets. Maximum and minimum temperature humidity index during the experimental period were 85.9 and 76, respectively. Intakes of DM, crude protein and net energy, 4% fat corrected milk, milk protein and average daily gain decreased with increasing roughage NDF contents (p<0.05). Intakes of ether extract (p<0.01) and dietary NDF (p>0.05) and milk fat (p<0.01) increased with increasing roughage NDF contents. The results support the conclusion that higher DM intake, optimal milk yield and compositions can be maintained with lower roughage NDF diets for dairy cows under tropical conditions.

• Asian-Australasian Journal of Animal Sciences
• /
• v.12 no.6
• /
• pp.908-913
• /
• 1999

This experiment was conducted in three trials to evaluate optimal ambient temperature for a novel milk replacer feeding system designed for early-weaned pigs, compared to commercial dry diets fed within a conventional hot nursery. A total of 165 PIC genotype pigs were weaned at $13.89{\pm}0.7$ days of age and allotted to one of two dietary treatments in three trials based on weight and litter origin. Each trial consisted of pigs fed dry diets (DD) and pigs fed milk replacer (MR) which was offered in one of 3 different ambient temperatures. Pigs fed milk replacer were housed in a specialized nursery building in which one half of each pen contained an enclosed hover that was thermostatically maintained at $32^{\circ}C$ while the exterior ambient temperature (where milk was fed) was set at either 17 (trial 1), 24 (trial 2) or $32^{\circ}C$ (trial 3). Pigs fed dry diets with the conventional nursery were maintained at $30^{\circ}C$ for each trial. From d 21 to d 49, all pigs were fed DD within a standardized hot nursery environment. During the first week (d 14-21), pigs fed MR showed increased ADG from 214% to 228% over control pigs fed DD (p<0.001), regardless of ambient temperature. As ambient temperature was increased from 17 to 24 to $32^{\circ}C$, ADG of MR-fed pigs was increased by 214%, 220% and 228% over those of pigs fed DD, respectively. ADFIs of MR-fed pigs at $17^{\circ}C$, $24^{\circ}C$, and $32^{\circ}C$ compared with pigs fed DD were increased by 108%, 139% and 164% from d 14 to d 21, respectively. Fed efficiency (G/F) of MR-fed pigs at $17^{\circ}C$, $24^{\circ}C$, and $32^{\circ}C$ compared with pigs fed DD were 199%, 162% and 139% of those of pigs fed DD, respectively. As ambient temperature increased, diarrhea scores showed a slight tendency to increase. The advantage of MR feeding was greater when the ambient temperature was higher, but G/F was impaired with increased ambient temperature. We conclude that ambient temperature within the specialized nursery influenced behavior, MR feed intake, and probably piglet energy expenditure. There were no differences between MR-fed and DD-fed pigs for ADG, ADFI and G/F in the subsequent growth period (d 21 to d 49, p>0.05). Maximal advantage of MR feeding was obtained at the intermediate ($24^{\circ}C$) ambient temperature during the overall period (p<0.05). Results from this experiment indicate that a milk replacer feeding system utilized in the early postweaning period can maximize pig growth performance, and that ADG, ADFI and G/F were affected by different ambient temperatures within MR-fed pigs. The high or low temperatures could not support the maximal growth of pigs fed MR.