• Asian-Australasian Journal of Animal Sciences
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• v.31 no.3
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• pp.379-385
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• 2018

Objective: The study aimed to evaluate sugarcane bagasse as roughage in lactating cow on feed intake, digestibility, ingestive behavior, milk production and composition, and microbial protein synthesis. Methods: Ten Girolando cows at initial body weight of $450{\pm}25.6kg$ and at $143.7{\pm}30.7days$ in milk were assigned in two $5{\times}5$ Latin square designs. Five 21-day experimental periods were adopted ($1^{\circ}$ to 14-day: diets adaptation period; $15^{\circ}$ to 21-day: data collection and sampling period). The diets consisted of four different levels of sugarcane bagasse (45%, 50%, 55%, and 60%) and a control diet, commonly adopted in the region, based on spineless cactus (25% sugarcane bagasse), formulated to meet 12 kg/d milk yield. Results: The dry matter (DM), organic matter (OM), and total digestible nutrients intakes and DM and OM digestibilities observed for 45% and 50% bagasse inclusion were similar to control diet, while that 55% and 60% bagasse inclusion were lower. Cows fed control diet, and bagasse diets of 45%, and 50% levels had the nutritional requirements attended, that guaranteed 12 kg/d of milk yield. The crude protein intake and digestibility of cows fed 45%, 50%, and 55% of bagasse inclusion were similar to control diet. The neutral detergent fiber (NDF) intake and digestibility differ for all bagasse diets related to control diet, while the non-fiber carbohydrates intake and digestibility for cows fed 45% of bagasse were similar for control diet. The intakes and digestibilities of nutrients decreased linearly in function of bagasse inclusion; NDF and indigestible NDF intakes did not vary. The ruminating time, feeding and rumination efficiency, microbial protein synthesis and milk yield decreased linearly with sugarcane bagasse inclusion. Conclusion: Sugarcane bagasse decreases milk production; however, its inclusion level in between 45% to 50% associated to concentrate could replace diets based on spineless cactus for crossbred dairy cow's producing 12 kg/d of milk.

• Asian-Australasian Journal of Animal Sciences
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• v.7 no.2
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• pp.239-248
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• 1994

To study the relationship between certain hormones and metabolites and between hormones and milk yield during different stage of lactation, six lactating Karan Swiss cows and six Murrah buffaloes were maintained. Growth hormone, insulin, $T_3$, $T_4$, glucose, BHBA, NEFA and milk yield were studied. Highly negative relationship of growth hormone with insulin and triiodothyronine in cows and marginally negative in buffaloes suggest that insulin and triiodothyronine aid in the process of partitioning of nutrients towards milk production through reducing the demands of nutrients by peripheral tissue. The significant and negative correlation of growth hormone with dry matter intake in both the species suggest that the availability of nutrients from the digestive tract play a role in the regulation of growth hormone secretion. Positive relationship of growth hormone with non esterified fatty acids in both the species suggest that high growth hormone levels may result in fat mobilization and thereby increase the availability of energy precursors for milk synthesis. Insulin was negatively correlated with milk yield and lactose content and positively with milk fat and protein but the degree of relationship varied. In both the species the relationship between triiodothyronine and milk yield was negative and between thyroxine and milk yield was positive. However, it was significant only in cows and not in buffaloes. Thyroxine was positively correlated with beta-hydroxybutyrate and non-esterified fatty acids with milk yield in both the species.

• Asian-Australasian Journal of Animal Sciences
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• v.10 no.4
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• pp.335-356
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• 1997

Injection of bovine growth hormone (bGH) to lactating dairy cows increases milk yield and yields of milk components including fat. It is generally believed that most of the anabolic effects derived from bGH in animal tissues are primarily mediated by IGF-1. IGF-1 is a strong anabolic peptide in the plasma of animals and exerts mitogenic and metabolic effects on target cells. Contrary to most protein hormones, the majority of IGF-1 in circulation is bound to the binding proteins (IGFBPs) which are known to be responsible for modifying the biological actions of IGF-1, thus making determinations of IGF-1 actions more difficult. On the other hand, fat is a major milk component and the greatest energy source in milk. Currently, the fat content of milk is one of the major criteria used in determining milk prices. It has been known that flavor and texture of dairy products are mainly affected by milk fat and its composition. Acetyl-CoA carboxylase (ACC) is the rate limiting enzyme which catalyzes the conversion of acetyl-CoA to malonyl-CoA for fatty acid synthesis in 1ipogenic tissues of animals including bovine lactating mammary glands. In addition to the short-tenn hormonal regulation of ACC by changes in the catalytic efficiency per enzyme molecule brought about by phosphorylation and dephosphorylation of the enzyme, the long-term hormonal regulation of ACC by changes in the number of enzyme molecules plays an essential role in control of ACC and lipogenesis. Insulin, at supraphysiological concentrations, binds to IGF-1 receptors, thereby mimicking the biological effects of IGF-1. The receptors for insulin and IGF-1 share structural and functional homology. Furthermore, epidermal growth factor increased ACC activity in rat hepatocytes and adipocytes. Therefore, it can be assumed that IGF-1 mediating bGH action may increase milk fat production by stimulation ACC with phosphorylation (short term) and/or increasing amounts of the enzyme proteins (long term). Consequently, the main purpose of this paper is to give the readers not only the galactopoietic effects of bGH, but also the insight of bGH action with regard to stimulating milk fat synthesis from the whole body to the molecular levels.

• Asian-Australasian Journal of Animal Sciences
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• v.33 no.6
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• pp.1012-1022
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• 2020

Objective: Caseins and fatty acids of milk are synthesized and secreted by the epithelial cells of the mammary gland. All-trans retinoic acid (ATRA), an active metabolite of vitamin A, has been shown to promote mammary development. This study was conducted to determine the effect of ATRA on casein synthesis and fatty acid composition in MAC-T cells. Methods: MAC-T cells were allowed to differentiate for 4 d, treated with ATRA (0, 1.0, 1.5, and 2.0 μM), and incubated for 3 d. We analyzed the fatty acid composition, the mRNA expression of casein and fatty acid synthesis-related genes, and the phosphorylation of casein synthesis-related proteins of MAC-T cells by gas chromatography, quantitative polymerase chain reaction, and western blotting, respectively. Results: In MAC-T cells, ATRA increased the mRNA levels of α_S1-casein and β-casein, janus kinase 2 (JAK2) and E74-like factor 5 of the signal transducer and activator of transcription 5 β (STAT5-β) pathway, ribosomal protein S6 kinase beta-1 (S6K1) and eukaryotic translation initiation factor 4E binding protein 1 of the mammalian target of rapamycin (mTOR) pathway, inhibited the mRNA expression of phosphoinositide 3-kinase and eukaryotic initiation factor 4E of the mTOR pathway, and promoted the phosphorylation of STAT5-β and S6K1 proteins. Additionally, ATRA increased the de novo synthesis of fatty acids, reduced the content of long-chain fatty acids, the ratio of monounsaturated fatty acids to saturated fatty acids (SFA), the ratio of polyunsaturated fatty acids (PUFA) to SFA, and the ratio of ω-6 to ω-3 PUFA. The mRNA levels of acetyl-CoA carboxylase 1, fatty acid synthase, lipoprotein lipase, stearoyl-CoA desaturase, peroxisome proliferator-activated receptor gamma, and sterol regulatory element-binding protein 1 (SREBP1) were enhanced by ATRA. Conclusion: ATRA promotes the synthesis of casein by regulating JAK2/STAT5 pathway and downstream mTOR signaling pathway, and it improves the fatty acid composition of MAC-T cells by regulating SREBP1-related genes.

• Asian-Australasian Journal of Animal Sciences
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• v.25 no.7
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• pp.971-979
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• 2012

Four, lactating dairy crossbreds ($50%{\times}50%$ Holstein Friesian${\times}$Native Zebu cattle) were randomly assigned according to a $2{\times}2$ factorial arrangement (two protein levels and two levels of mangosteen peel pellets (Mago-pel)) in a $4{\times}4$ Latin square design to receive four dietary treatments. All cows received concentrate at a proportion of 1 kg concentrate per 2 kg of milk yield, and urea-treated 5% rice straw (UTRS) was given ad libitum. It was found that total dry matter intakes, nutrient digestibility, ruminal pH and $NH_3$-N concentrations were not affected (p>0.05) by treatments. Concentrations of ruminal pH and $NH_3$-N were not affected by dietary treatments although the concentration of BUN varied significantly (p<0.05) between protein levels (p<0.05). The populations of rumen bacteria and fungal zoospores did not differ among treatments (p>0.05); however, the population of protozoa was decreased (p<0.05) when cows received Mago-pel supplementation. The composition of the population of bacteria, identified by real-time PCR technique, including total bacteria, methanogens, Fibrobacter succinogenes and Ruminococcus albus was similar (p>0.05) among dietary treatments (p>0.05); however, copy numbers of Ruminococcus flavefaciens was increased when protein level increased (p<0.05). Microbial protein synthesis, in terms of both quantity and efficiency, was enriched by Mago-pel supplementation. Milk yield was greatest in cows fed UTRS based diets with concentrate containing protein at 16% CP with Mago-pel, but were lowest without Mago-pel (p<0.05). In addition, protein level and supplementation of Mago-pel did not affect (p>0.05) milk composition except solids-not-fat which was higher in cows fed the diet with 19% CP. Therefore, feeding a concentrate containing 16% CP together with 300 g/hd/d Mago-pel supplementation results in changes in rumen fermentation and microbial population and improvements in milk production in lactating dairy crossbreds fed on UTRS.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.7
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• pp.963-967
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• 2002

Eighteen crossbred goats were selected from the Institute's goat herd to determine the changes in hormones, blood metabolites and yield and composition of milk during lactation. The blood and milk samples were collected from each goat in a heparinized vacutainer tubes at fortnightly interval for a period of 150 days. In milk samples, fat, protein and lactose contents were estimated while in blood plasma hormones viz., prolactin, GH, cortisol, insulin, $T_4$ and $T_3$ were measured using radioimmunoassay methods. The plasma concentration of prolactin, GH and cortisol were high during early lactation when the goats acquired peak milk yield. During remainder of lactation their concentration varied. The high NEFA concentration during early lactation indicated mobilization of body reserves as the body weights also decrease during early lactation. However, with the advancement of lactation, the body weights of the goats and the concentration of NEFA declined which indicated utilization of NEFA for energy yielding purposes in addition to fatty acid synthesis. The ambient temperatures did not influence plasma concentration of prolactin, GH, insulin, $T_3$ and $T_4$ during the lactation cycle. The fat content of milk varied significantly (p<0.01) but protein and lactose content of milk remains unchanged during different stages of lactation. Growth hormone was positively correlated with insulin (p<0.05) during lactation while prolactin had a positive correlation with lactose and plasma NEFA (p<0.01) and negative correlation with $T_3$ (p<0.05).

• Asian-Australasian Journal of Animal Sciences
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• v.26 no.9
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• pp.1295-1303
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• 2013

The aim of this study was to determine the effect of different physical forms and urea treatment of rice straw on feed intake, rumen fermentation, and milk production. Four, multiparous Holstein crossbred dairy cows in mid-lactation with initial body weight (BW) of $409{\pm}20kg$ were randomly assigned according to a $4{\times}4$ Latin square design to receive four dietary treatments. The dietary treatments were as follows: untreated, long form rice straw (LRS), urea-treated (5%), long form rice straw (5% ULRS), urea-treated (2.5%), long form rice straw (2.5% ULRS) and urea-treated (2.5%), chopped (4 cm) rice straw (2.5% UCRS). Cows were fed with concentrate diets at a ratio of concentrate to milk yield of 1:2 and rice straw was fed ad libitum. The findings revealed significant improvements in total DM intake and digestibility by using long and short forms of urea-treated rice straw (p<0.05). Ruminal pH was not altered among all treatments (p>0.05), whereas ruminal $NH_3$-N, BUN and MUN were found to be increased (p<0.01) by urea-treated rice straw as compared with untreated rice straw. Volatile fatty acids (VFAs) concentrations especially those of acetic acid were decreased (p<0.05) and those of propionic acid were increased (p<0.05), thus acetic acid:propionic acid was subsequently lowered (p<0.05) in cows fed with long or short forms of urea-treated rice straw. The 2.5% ULRS and 2.5% UCRS had greater microbial protein synthesis and was greatest when cows were fed with 5% ULRS. The urea-treated rice straw fed groups had increased milk yield (p<0.05), while lower feed cost and greater economic return was in the 2.5% ULRS and 2.5% UCRS (p<0.01). From these results, it could be concluded that 2.5% ULRS could replace 5% ULRS used as a roughage source to maintain feed intake, rumen fermentation, efficiency of microbial protein synthesis, milk production and economical return in mid-lactating dairy cows.

• Journal of the Korean Applied Science and Technology
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• v.30 no.3
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• pp.551-559
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• 2013

To investigate the adhesion effect of sodium bisulfite content in making blocked isocyanate, wood adhesive PB-1, PB-2, PB-3 and PB-4 containing sodium bisulfite content of 15%, 22.5%, 30% and 37.5% were synthesized respectively. As a result, when the amount of sodium bisulfite increased in adhesives, the tensile strength was found to be proportionally increased. The final adhesive mixtures were manufactured using a two-components system which are prepared by mixing two separate protein and BI solutions due to the precipitate in the adhesives. As PVA was added to adhesives to increase tenacity, the plywood dehiscence phenomenon after cold pressing process was declined. By addition of PVA, the tensile strength was improved up to $6.5{\sim}7kgf/cm^2$ with BI/protein ratio from 1:6 up to 1:8. Phase separation between milk fat and aqueous layer was disappeared after addition of emulsifier, Tween 20. Additon of Tween 20 showed tensile strength up to $5{\sim}6.5 kgf/cm^2$ at NCO/protein ratio of 1:12 ~ 1:14 without phase separation.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.3
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• pp.348-352
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• 2003

An investigation was made into the protein profile of colostrum/milk of ten Murrah buffaloes and of their ten buffalo calves during their first week of neonatal life to study the materno-neonatal transfer of immunoglobulins (Ig). Calves were pail fed 3.5 liter of colostrum and/or milk per calf/day exclusively from their dam. First blood sample from newborn calves was collected before colostrum feeding on the day of birth (day zero) and the sampling continued daily for seven days after colostrum/milk feeding. Colostrum/milk Ig and IgG values were $4.82{\pm}2.60$, $2.19{\pm}1.90$, $1.12{\pm}0.82$, $0.69{\pm}0.44$, $0.59{\pm}0.31$, $0.47{\pm}0.20$, $0.40{\pm}0.22$, $0.40{\pm}0.25$ and $3.58{\pm}1.90$, $1.08{\pm}0.92$, $0.52{\pm}0.40$, $0.31{\pm}0.20$, $0.27{\pm}0.14$, $0.22{\pm}0.08$, $0.18{\pm}0.09$, $0.14{\pm}0.08$ respectively during 0-7 days post partum. The concentration of total colostrum/milk proteins, Ig, IgG and albumin were highest within 12 h post-partum. Thereafter, the concentrations followed a declining trend which may be attributed to the reduced transfer of proteins from the maternal blood, declining synthesis by the mammary glands and/or depletion of stored proteins. The concentrations of plasma Ig and IgG before colostrum feeding on day zero were $0.42{\pm}0.09$ and $0.08{\pm}0.03$ respectively. The levels of plasma Ig were $1.90{\pm}0.37$, $1.80{\pm}0.31$, $1.80{\pm}0.26$, $1.81{\pm}0.28$, $1.78{\pm}0.31$, $1.79{\pm}0.21$, $1.80{\pm}0.32$ and of IgG were $1.57{\pm}0.41$, $1.30{\pm}0.29$, $1.31{\pm}0.21$, $1.27{\pm}0.18$, $1.23{\pm}0.21$, $1.23{\pm}0.16$, $1.26{\pm}0.21$ on days 1-7 after birth after colostrum/milk feeding. The concentrations of total plasma proteins, Ig, IgG were lowest before colostrum feeding and increased significantly (p<0.05) after colostrum feeding in buffalo neonates. The results suggest that the highest amounts of colostral Ig and IgG were available on the day of parturition and thus the calves should receive colostrum as early after birth as possible. Colostrum Ig and IgG concentrations were not correlated to plasma Ig and IgG concentrations in the post-suckle buffalo calves and therefore, colostrum Ig and IgG concentrations were probably not the principle determinants of calf post-suckle plasma Ig and IgG concentrations.

• Asian-Australasian Journal of Animal Sciences
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• v.27 no.8
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• pp.1181-1188
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• 2014

The aim of this study was to evaluate protein expression patterns of liver in response to subacute ruminal acidosis (SARA) induced by high-concentrate diet. Sixteen healthy mid-lactating goats were randomly divided into 2 groups and fed either a high-forage (HF) diet or a high-concentrate (HC) diet. The HC diet was expected to induce SARA. After ensuring the occurrence of SARA, liver samples were collected. Proteome analysis with differential in gel electrophoresis technology revealed that, 15 proteins were significantly modulated in liver in a comparison between HF and HC-fed goats. These proteins were found mainly associated with metabolism and energy transfer after identified by matrix-assisted laser desorption ionization/time of flight. The results indicated that glucose, lipid and protein catabolism could be enhanced when SARA occurred. It prompted that glucose, lipid and amine acid in the liver mainly participated in oxidation and energy supply when SARA occurred, which possibly consumed more precursors involved in milk protein and milk fat synthesis. These results suggest new candidate proteins that may contribute to a better understanding of the mechanisms that mediate liver adaptation to SARA.