• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1400-1410
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• 2004

Eight crossbred (75% Holstein Friesian) cows in mid-lactation were randomly assigned to a switchback design with a 2x2 factorial arrangement to evaluate two nonstructural carbohydrate (NSC) sources (corn meal and cassava chips) with different rumen degradability and used at two levels of NSC (55 vs. 75%) with protein source (supplied by urea in the concentrate mix). The treatments were 1) Low degradable low level of corn (55%) 2) Low degradable high level of corn (75%) 3) High degradable low level of cassava (55%) and 4) High degradable high level of cassava (75%). The cows were offered the treatment concentrate at a ratio to milk yield at 1:2. Urea-treated rice straw was offered ad libitum as the roughage and supplement with 1 kg/hd/d cassava hay. The results revealed that total DM intake, BW and digestion coefficients of DM were not affected by either level or source of energy. Rumen fermentation parameters; NH3-N, blood urea nitrogen and milk urea nitrogen were unaffected by source of energy, but were dramatically increased by level of NSC. Rumen microorganism populations were not affected (p>0.05) by source of energy, but fungal zoospores were greater for cassava-based concentrate than corn-based concentrate. Milk production and milk composition were not affected significantly by diets containing either source or level of NSC, however concentrate than corn-based concentrate averaging (4.4 and 4.2, respectively). Likewise, income over feed, as estimated from 3.5% FCM, was higher on cassava-based concentrate than corn-based concentrate averaging (54.0 and 51.4 US$/mo, respectively). These results indicate that feeding diets containing either cassava-based diets and/or a higher of oncentrates up to 75% of DM with NPN (supplied by urea up to 4.5% of DM) can be used in dairy rations without altering rumen ecology or animal performance compared with corn-based concentrate.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.11
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• pp.1573-1578
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• 2002

This study was conducted to investigate the effects of diets that contained different levels of fungal treated wheat straw on the intake, digestibility and performance of lactating cows. Eight primiparous Holstein cows, in late lactation ranging from $170{\pm}10$ days in milk and yielding $14.3{\pm}1.3$ kg/d of fat corrected milk (FCM) were allocated into four diets with 0, 10, 20 and 30% fungal (Pleurotus ostreatus coded P-41) treated wheat straw in a $4{\times}4$ Latin Square experiment. The daily intake of DM, OM, DOM, CP and TDN were not affected by substitution of alfalfa hay with fungal treated wheat straw. Inclusion of the treated straw at different levels in the diet did not affect the digestibility of nutrients, except for the ADF that was significantly (p<0.05) reduced in the diet contained 30% treated straw. The types of the diet did not significantly affect daily milk and FCM production. The milk composition including fat, protein, lactose, solid non-fat (SNF) and total solid (TS) were not statistically (p>0.05) different among the diets. All cows gained weight, but the inclusion of treated straw to the diet significantly (p<0.05) increased the body weight gain and the highest amount was obtained in the diet containing 20% treated. Inclusion of fungal treated wheat straw up to 30% of the diet of lactating cows supplemented with a protein source such as cottonseed meal had not affected the nutrients intake and lactation performance.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.5
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• pp.659-666
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• 2009

Metabolizable protein (MP) supply and amino acid balance in the intestine were manipulated through selection of highly digestible rumen-undegradable protein (RUP) sources and protected methionine (Met) supplementation. Four ruminallycannulated, multiparous Holstein cows averaging 193${\pm}$13 days in milk were used in a 4${\times}$4 Latin square design to assess N utilization and milk production responses to changes in RUP level, post-ruminal RUP digestibility and protected Met supplementation. Treatments were A) 14.0% crude protein (CP), 8.0% rumen degradable protein (RDP) and 6.0% RUP of low intestinal digestibility (HiRUP-LoDRUP); B) 14.1% CP, 8.1% RDP and 6.0% RUP of high intestinal digestibility (HiRUP-HiDRUP); C) 13.1% CP, 7.9% RDP and 5.2% RUP of high intestinal digestibility (LoRUP-HiDRUP), and D) 13.1% CP, 7.9% RDP and 5.2% RUP of high intestinal digestibility plus rumen escape sources of Met (LoRUP-HiDRUP+Met). Experimental diets were formulated to have similar concentrations of RDP, net energy of lactation ($NE_L$), neutral detergent fiber (NDF), acid detergent fiber (ADF), calcium, phosphorus and ether extract using the NRC model (2001). Results showed that dry matter intake (DMI), production of milk fat and protein were similar among treatments. Milk production was similar for diet HiRUP-LoDRUP, HiRUP-HiDRUP and LoRUP-HiDRUP+Met, and significantly higher than diet LoRUP-HiDRUP. Milk fat and protein percentage were higher for cows receiving HiDRUP treatments, with the greatest increases in the diet LoRUP-HiDRUP+Met. There was no significant change in ruminal pH, $NH_3g-N$ and volatile fatty acid (VFA) concentration among all treatments. Apparent digestibility of dry matter (DM), CP, NDF and ADF and estimated bacterial CP synthesis were similar for all treatments. Nitrogen intakes, blood and milk urea-N concentrations were significantly higher for cows receiving HiRUP diets. Urine volume and total urinary N excretion were significantly lowered by LoRUP diets. Lowering dietary RUP level while supplementing the highly digestible RUP source with rumen escape sources of Met resulted in similar milk production, maximal milk fat and protein concentration and maximum N efficiency, indicating that post-ruminal digestibility of RUP and amino acid balance in the small intestine can be more important than total RUP supplementation.

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.11
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• pp.1513-1520
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• 2009

Forty-six Holstein heifers were used in a completely randomized design and assigned to 1 of 2 treatments to evaluate the effects of 2 diets varying in ruminal fermentable carbohydrate sources, namely ground corn (GC) and rolled wheat (RW), on metabolism and performance of primiparous cows in the periparturient period. The heifers were fed diets as a total mixed ration (TMR) with similar energy and crude protein content including i) 18.57% GC, or ii) 18.57% RW from -24.13${\pm}$7.73 d relative to expected calving until calving. After calving, all animals received the same lactation diet until 28 d. Animals were group fed from the beginning of the study to -7 d relative to expected calving, fed individually from d -7 to 7 days in milk (DIM), and again group fed to 28 DIM. The pre-partum diets affected (p<0.05) dry matter intake (DMI), energy intake, energy balance (EB) and urinary pH during the last week pre-partum. There was no effect of pre-partum carbohydrate source on overall plasma concentration of glucose, nonesterified fatty acid (NEFA), $\beta$-hydroxybutyrate (BHBA), albumin, triglyceride (TG), cholesterol, aspartate aminotransferase (AST), insulin, and cortisol during the periparturient period. Cows fed the RW diet during the pre-partum period had greater calcium for the first week (p<0.05) and during 28 d (p = 0.08) of lactation compared with heifers fed the GC diet. Primiparous cows fed the RW diet produced greater milk protein content and yield (p<0.05). Primiparous cows fed the RW diet had lower milk urea nitrogen (MUN) and somatic cell count (SCC) than cows fed the GC diet (p<0.05). The results of this study show that feeding pre-partum diets with a rapidly fermentable source of starch but low energy content can improve animal metabolism and performance and smooth the transition of primiparous Holstein cows from gestation to lactation.

• Journal of The Korean Society of Grassland and Forage Science
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• v.36 no.1
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• pp.29-33
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• 2016

In order to provide basic data to predict changes of milk components in milk yield, this study was conducted to compare nutritive values of diets collected from organic dairy farms (ODF) and conventional dairy farms (CDF) of Chungnam and Jeonbuk in Korea. The contents of crude fat, crude fiver, neutral detergent fiber, and acid detergent fiber in diets of ODF were significantly (p<0.05) higher compared to those of CDF. The contents of crude protein and crude ash in ODF were also higher (p<0.05) than those of CDF. The contents of calcium, ferrum, and phosphorus in diets of ODF were similar to those of CDF. The contents of potassium, magnesium, and iodine in diets of ODF were higher (p<0.05) than those of CDF. The contents of total saturated and unsaturated fatty acids in diets of ODF were higher (p<0.05) compared to those of CDF. The contents of oleic acid, linoleic acid, and linolenic acid in diets of ODF were higher (p<0.05) compared to those of CDF. However, the contents of myristic acid, palmitic acid, and stearic acid in diets of ODF were lower (p<0.05) compared to those of CDF.

• Journal of Animal Science and Technology
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• v.49 no.3
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• pp.359-368
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• 2007

Holstein cows(n=12) were assigned to one of three diets containing control diet and diets containing a microbial culture, 50ml(T1) and 100ml(T2) SDN(R)(amicrobial culture), per day. The basal diet containing concentrate mixture, corn silage and timothy hay were fed midlactating cows for 12 weeks. Milk production tended to be higher for cows fed T2 diet (20.8kg/day) than fed T1(19.7kg/d) and control diet (19.2kg/day).  There was a tendency of an increase in 4% FCM for cows fed T2 diet(19.6kg/day) than T1(18.8kg/d) and control diet(18.4kg/day). Milk components were not found to be different between cows fed control diet and SDN(R) diets. There was a tendency an increase in milk protein for cows fed control diet(3.43%) compared with microbial diets, T1 and T2(3.08% and 3.20%). However, milk protein production was not significantly different between control diet(0.65kg/d) and T1(0.61kg/d) or T2(0.67kg/d). Somatic cell counts for cows fed T1(72,000) and T2(60,000/ml) were lower than cows fed control diet (108,000/ml) (P<0.05). In conclusion, the cows that were fed diets containing SDN(R) as a microbial culture resulted a tendency of an increase in milk production and a reduction of somatic cell counts which indicates improved milk quality and hygiene.

• Journal of Animal Science and Technology
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• v.48 no.4
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• pp.555-562
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• 2006

The objective of this study was to evaluate the effects of dietary cation-anion difference (DCAD) with or without ruminally protected fat and niacin on the thermoregulatory ability, milk yield and milk composition of lactating dairy cows during summer in Korea. Thirty mid-lactating Holstein cows (134±12.4 DIM and 23.4±2.3kg/d of milk yield) were divided into three groups (10 animals/group). Cows were housed in a free-stall barn and were provided with forced- air ventilation (wind velocity = 4 m/s) using 41 cm diameter fans. Diet one was formulated to contain low DCAD (+15 DCAD) while the remaining two diets were higher in DCAD (+30 DCAD). One higher DCAD diet was formulated to contain by-pass fat and the second higher DCAD diet contained the niacin along with by-pass fat. The maximum ambient temperature during July was 28.5℃ which could be seen as a period of mild heat stress. As summer progressed, August was characterized as a severe heat stress condition with maximum ambient temperature (32.4℃) and THI (74.0). Dry matter, crude protein and total digestible nutrients intake was not affected by the DCAD level and supplementation of ruminally protected fat or niacin. Milk production was higher in cows fed diets supplemented with fat and niacin than those fed un-supplemented diet. No difference in milk yield was observed in cows fed diets supplemented with fat or niacin plus fat. Milk fat and rectal temperature were not affected by the DCAD level and supplementation of ruminally protected fat or niacin. However, respiration rate was decreased in cows fed diets supplemented with either fat or fat and niacin compared to those fed. The results of the present study indicated that higher DCAD (+30) and supplementation of fat along with niacin can somehow mitigate the negative effects of heat stress on milk yield and physiology of lactating Holsteins during July and August in Korea. In present study reduced respiration rate and increased milk yield in lactating cows may be attributed to the cooling effect of supplemented fat along with vasodilatory functions of niacin. (Key Words: DCAD, Heat stress, THI, milk yield, Milk fat, Holstein)

• Food Science of Animal Resources
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• v.41 no.1
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• pp.8-15
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• 2021

Vegetarians have claimed and actively promoted the advantages of plant-based alternative milks as the best option for human nutrition and health, compared to the natural dairy milk. However, numerous scientific evidences and reports have demonstrated that the natural milk possesses more beneficial nutrients and bioactive components than artificially manufactured plant-derived milks. The biochemical and nutritional advantages and functionalities of natural dairy milk cannot be replaced by man-made or crafted plant-based beverage products. On the other hand, the tremendous increase in production and consumption of the plant-based alternative milks in recent years has led a serious business downturn in traditional roles and stability of the dairy industry, especially in the major dairy producing Western countries. Although plant-based milk alternatives may have some benefits on nutrition and health of certain consumers, the plant-derived alternative milks may not overshadow the true values of natural milk. Milk is not a high fat and high cholesterol food as animal meat products. Unlike plant-based alternative milks, natural milk contains many bioactive as well as antiappetizing peptides, which can reduce body weight. It has proven that taking low-fat, cultured and lactase treated milk and dairy products with other diversified nutritionally balanced diets have been shown to be healthier dietary option than plant-based milk/foods alone.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.10
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• pp.1395-1399
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• 2004

The objective of this study was to evaluate the effect of dietary fat inclusion on nutrient intake, body weight, milk production, return to estrus, pregnancy and lambing of winter-lambing, postpartum Awassi ewes. Thirty multiparous, winter-lambing Awassi ewes (body weight=51${\pm}$7.0 kg) were randomly assigned to three dietary treatments (n=10) for 62 days using a completely randomized design. Experimental diets were isonitrogenous, and were formulated to contain 0 (CON), 2.5 (MF), and 5% (HF) added fat, and 33% of the dietary crude protein (CP) as undegradable intake protein (UIP). On day 26 postpartum (day 0=parturition), ewes and their lambs were housed in individual pens for 28 days. Feed offered and refused was recorded daily. At the end of this period, ewes and their lambs within each treatment were combined into one group and fed their respective diet ad libitum. One fertile Awassi ram fitted with a marking harness was allowed with each group for 34 days. No significant (p>0.05) differences in dry matter intake, organic matter intake, and crude protein intake were observed for ewes fed the three experimental diets. No difference was observed in metabolizable energy intake (MEI) for ewes fed the CON and the MF diets (average 8.3 Mcal/d) diet. However, ewes fed the HF diet had greater(p<0.05) MEI compared with the rest of the treatments. Ewe body weights increased throughout the study, unaffected by the experimental diets. No significant differences in milk production were found among ewes fed the three experimental diets. No significant differences were observed in pregnancy rate (6/10, 5/10, 6/10 for CON, MF and HF diets, respectively), lambing rate and the number of lambs per ewe among the three treatments. postpartum reproductive performance of well-fed, winter-lambing Awassi ewes.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.1
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• pp.35-43
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• 2020

Objective: The aim of this research was to evaluate the effect of different concentrate levels in diets based on cactus Opuntia Stricta (Haw.) Haw cladodes on the performance of lactating Girolando cows. Methods: The experiment involved 10 Girolando multiparous dairy cows at 512.6 kg of body weight (BW) and producing 13.2 kg milk/d, allocated into two 5×5 Latin squares. The experimental treatments consisted of control diet composed by cactus Nopalea cochenillifera. Salm-Dyck. cladodes (Nopalea), forage sorghum silage and concentrate at 20% on dry matter (DM) basis, and four concentrate levels diets (20%, 24%, 28%, and 32%) plus cactus Opuntia stricta (Haw.) Haw. cladodes (Opuntia) and forage sorghum silage. Results: Regarding cows fed control diet, the nutrients intake were greater than for cows fed with cactus Opuntia and concentrate. Regarding concentrate levels, intakes of DM, organic matter (OM), crude protein (CP), non-fiber carbohydrates (NFC), and total digestible nutrients of cows increased linearly. Organic matter, CP, and NDF digestibilities were similar in between to control diet and cactus Opuntia-based diets. The digestibility of NFC increased linearly when the concentrate was inserted. The N balance was the same for control diet and cactus Opuntia-based diets, irrespective the concentrate levels. Conclusion: For cows producing 14 kg/d with 3.5% of fat, it is recommended 32% of concentrate to be included in cactus Opuntia-based diets, and the increase in concentrate level promotes a linear increase in milk yield.