• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.3
• /
• pp.315-320
• /
• 2002

Test-day records (n=13677) sampled from 896 ewes in 5-9 (${\mu}$=7.5) monthly test-days were used to estimate genetic and phenotypic parameters of test-day yields, lactation milk yield (TMY), length of the milking period (DAYS) and three measures of persistency of milk yield in Boutsico dairy sheep. Τhe measures of persistency were the slope of the regression line (${\beta}$), the coefficient of variation (CV) of the test-day milk yields and the maximum to average daily milk yield ratio (MA). The estimates of variance components were obtained under a linear mixed model by restricted maximum likelihood. The heritability of test-day yields ranged from 0.15 to 0.24. DAYS were found to be heritable ($h^2$=0.11). Heritability estimates of ${\beta}$, CV and MA were 0.15, 0.13, 0.10, respectively. Selection for maximum lactation yields is expected to result in prolonged milking periods, high rates of decline of yields after peak production, variable test-day yields and higher litter sizes. Selection for flatter lactation curves would reduce lactation yields, increase slightly the length of the milking period and decrease yield variation as well as litter size. The most accurate prediction of TMY was obtained with a linear regression model with the first five test-day records.

• Asian-Australasian Journal of Animal Sciences
• /
• v.16 no.5
• /
• pp.677-684
• /
• 2003

Twenty eight multiparous lactating cows were utilized in an experiment to evaluate the response to an exogenous fibrolytic enzyme on their lactational performance during early lactation period (in terms of milk production, milk composition, feed intake, milking efficiency, body weight change) and the exact time of this response. Cows were randomized into two groups (14 each) with similar parities and were fed a concentrate ration of barley, ground corn, soybean meal, and wheat bran and roughage ration of alfalfa hay. One of the two groups was supplemented with the fibrolytic enzyme immediately after parturition up to 100 post partum. The experiment was of two phases with 50 days each. The enzyme, which has a cellulase/hemicellulase activity (derived from Trichoderma group), was added to the concentrate part of the ration in a dry powder form. Milk production, 3.5% fat corrected milk, energy corrected milk were higher (p<0.05) for cows fed treated diet. At the same time, No differences were observed in percentages of milk components, feed intake, body weight, body weight change, or rectal temperature for the whole experimental period or during any of the two phases. Efficiency of milk production was higher (p<0.05) for treatment group cows than for that of the control ones. However, efficiency was better during the second phase than during the first phase. Feeding enzyme treated diets to dairy cows improved lactational performance during early 100 day of the lactation period. However, the first 50 days of lactation looked to be the critical.

• Reproductive and Developmental Biology
• /
• v.40 no.2
• /
• pp.23-26
• /
• 2016

Transcription factor called activating enhancer binding protein 2C (AP2-gamma) is found in a variety of species and expressed from oocyte stage onwards, particularly restricted to the trophectoderm. Recent studies demonstrated that ablation of Tfap2c led to failure of tight junction biogenesis, particularly the knock-down embryos of Tfap2c did not form cavity from morula to blastocyst in mouse and pig. We speculated that the Tfa2pc may also be involved in desmosome biogenesis because blastocoel formation is coincident with the establishment of desmosome. To determine this, we depleted Tfap2c injecting siRNA into one-cell zygote and analysed the expression levels of genes that are required for desmosome complex such as PkP2, Pkp3, Dsc2, and Dsg2. We found only Pkp3 was up-regulated in the knockdowned morula embryos. Interestingly, upstream region of Pkp3 had putative Tfap2c binding sites. In conclusion, our results suggest that Tfap2c is not a crucial factor but somehow it might be involved in desmosome biogenesis directly or indirectly via Pkp3.

• Journal of Dairy Science and Biotechnology
• /
• v.14 no.1
• /
• pp.17-31
• /
• 1996

This study was to investigate current regulatory status of nutrition labeling in advanced countries, such as US and Japan. In US, the mandatory and voluntary components and the order in which they must appear are total calories, total fat, cholesterol, sodium, potassium, total carbohydrate, protein vitamin and iron. The amount of each nutrient must be reported on the basis of the serving size except vitamines and minerals. In Japan, new regulatation on nutrition labeling was made in 1995. For nutrition labeling on processed food, a standard must be appeared and it is mandatory. The union of Europe and Codex also newly regulated on nutrition labeling. It is time to make new regulation on nutrition labeling for being advanced country.

• Journal of Dairy Science and Biotechnology
• /
• v.15 no.1
• /
• pp.27-32
• /
• 1997

Most lipids in milk are dispetsed as the form of fat globules. Apical portion of plasma membrane is coated with fat globules, which are synthesized from mammary epithelial cells and then secreted into the lumen. The unique phenomenon in separation of the plasma membrane from the cell is observed only in mammary system. It has been suggested that milk fat globule membrane(MFGM) is formed from endoplasmic reticulum, Golgi apparatus, secretory granule to plasma membrane. For this reason MFGM is important for nuderstanding the structure and function of biological membrane. Because MFGM also plays an important role in inhibition of lipase action, stimulation of nutrient digestion and absorption, emulsion or function as natural liposome, study of the major components in MFGM will provide the opportunity for more broad industrial uses of MFGM in the future.

• Journal of Dairy Science and Biotechnology
• /
• v.35 no.2
• /
• pp.85-92
• /
• 2017

Four different types of cheeses were measure detailed changes in the mineral concentrations of cheese-serum during ripening. Concentrations of minerals in cheese juice were measured. The pH value using the low pH method (LPM) cheese was significantly (p<0.05) lower than that of other cheeses. Similarly the total Ca, S, Mg, and P contents of LPM cheese were significantly lower in than those of other cheeses. Ca, S, Mg, and P remained in colloidal form, while other minerals were mostly in soluble forms after 1 day. The minerals associated with the structure of cheese (i.e., casein or colloidal calcium phosphate) remained largely insoluble even after 1 month of ripening.

• Asian-Australasian Journal of Animal Sciences
• /
• v.26 no.9
• /
• pp.1237-1246
• /
• 2013

The objective of this study was to estimate variance components and genetic parameters for lactation milk yield (LY), lactation length (LL), average milk yield per day (YD), initial milk yield (IY), peak milk yield (PY), days to peak (DP) and parameters (ln(a) and c) of the modified incomplete gamma function (MIG) in an Ethiopian multibreed dairy cattle population. The dataset was composed of 5,507 lactation records collected from 1,639 cows in three locations (Bako, Debre Zeit and Holetta) in Ethiopia from 1977 to 2010. Parameters for MIG were obtained from regression analysis of monthly test-day milk data on days in milk. The cows were purebred (Bos indicus) Boran (B) and Horro (H) and their crosses with different fractions of Friesian (F), Jersey (J) and Simmental (S). There were 23 breed groups (B, H, and their crossbreds with F, J, and S) in the population. Fixed and mixed models were used to analyse the data. The fixed model considered herd-year-season, parity and breed group as fixed effects, and residual as random. The single and two-traits mixed animal repeatability models, considered the fixed effects of herd-year-season and parity subclasses, breed as a function of cow H, F, J, and S breed fractions and general heterosis as a function of heterozygosity, and the random additive animal, permanent environment, and residual effects. For the analysis of LY, LL was added as a fixed covariate to all models. Variance components and genetic parameters were estimated using average information restricted maximum likelihood procedures. The results indicated that all traits were affected (p<0.001) by the considered fixed effects. High grade $B{\times}F$ cows (3/16B 13/16F) had the highest least squares means (LSM) for LY ($2,490{\pm}178.9kg$), IY ($10.5{\pm}0.8kg$), PY ($12.7{\pm}0.9kg$), YD ($7.6{\pm}0.55kg$) and LL ($361.4{\pm}31.2d$), while B cows had the lowest LSM values for these traits. The LSM of LY, IY, YD, and PY tended to increase from the first to the fifth parity. Single-trait analyses yielded low heritability ($0.03{\pm}0.03$ and $0.08{\pm}0.02$) and repeatability ($0.14{\pm}0.01$ to $0.24{\pm}0.02$) estimates for LL, DP and parameter c. Medium heritability ($0.21{\pm}0.03$ to $0.33{\pm}0.04$) and repeatability ($0.27{\pm}0.02$ to $0.53{\pm}0.01$) estimates were obtained for LY, IY, PY, YD and ln(a). Genetic correlations between LY, IY, PY, YD, ln(a), and LL ranged from 0.59 to 0.99. Spearman's rank correlations between sire estimated breeding values for LY, LL, IY, PY, YD, ln(a) and c were positive (0.67 to 0.99, p<0.001). These results suggested that selection for IY, PY, YD, or LY would genetically improve lactation milk yield in this Ethiopian dairy cattle population.

• Asian-Australasian Journal of Animal Sciences
• /
• v.25 no.9
• /
• pp.1216-1222
• /
• 2012

Somatic cells count (SCC), milk yield (MY) and pedigree information of 2,791 first lactation cows that calved between 1990 and 2010 on 259 Thai farms were used to estimate genetic parameters and trends for SCC and its genetic association with MY. The SCC were log-transformed (lnSCC) to make them normally distributed. An average information-restricted maximum likelihood procedure was used to estimate variance components. A bivariate animal model that considered herd-yr-season, calving age, and regression additive genetic group as fixed effects, and animal and residual as random effects was used for genetic evaluation. Heritability estimates were 0.12 (SE = 0.19) for lnSCC, and 0.31 (SE = 0.06) for MY. The genetic correlation estimate between lnSCC and MY was 0.26 (SE = 0.59). Mean yearly estimated breeding values during the last 20 years increased for SCC (49.02 cells/ml/yr, SE = 26.81 cells/ml/yr; p = 0.08), but not for MY (0.37 kg/yr, SE = 0.87 kg/yr; p = 0.68). Sire average breeding values for SCC and MY were higher than those of cows and dams (p<0.01). Heritability estimates for lnSCC and MY and their low but positive genetic correlation suggested that selection for low SCC may be feasible in this population as it is in other populations of dairy cows. Thus, selection for high MY and low SCC should be encouraged in Thai dairy improvement programs to increase profitability by improving both cow health and milk yield.

• Asian-Australasian Journal of Animal Sciences
• /
• v.24 no.1
• /
• pp.65-72
• /
• 2011

Twenty-four Holstein dairy cows were used to evaluate the single and combined effects of different levels of crude protein (CP) and monensin treatment during early lactation on blood metabolites, milk yield and digestion of dairy cows. The experiment was designed as a completely randomized block with a $3{\times}2$ factorial arrangement of treatments. The factors were three concentrations of CP supplement (19.5, 21.4, and 23.4% of dry matter) and two levels of monensin (0 and 350 mg per cow per day). The experiment consisted of three phases and each phase was 3 wk in length. Monensin did not affect milk yield, lactose, solids-non-fat (SNF), blood glucose, triglyceride and DMI, but increased blood cholesterol, blood urea nitrogen (BUN), insulin and reduced blood ${\beta}$-hydroxybutyrate (BHBA), milk fat and protein percentage. Monensin premix significantly decreased rumen ammonia, but rumen pH and microbial protein synthesis were not affected by monensin treatment. Increasing dietary CP improved milk and protein production, but did not alter the other components of milk. Digestibility of NDF, ADF, CP were improved by increasing dietary CP. Increasing dietary CP from 19.5 to 21.4% had no significant effect on ruminal ammonia, but increasing CP to 23.4% significantly increased ruminal ammonia. There was a linear relationship between level of crude protein in the diet and volume of urine excretion. Microbial protein synthesis was affected by increasing CP level; in this way maximum protein synthesis was achieved at 23.4% CP.

• Asian-Australasian Journal of Animal Sciences
• /
• v.28 no.3
• /
• pp.311-317
• /
• 2015

Phenotypic characterization and body biometric in 13 traits (height at withers, body length, chest girth, paunch girth, ear length, tail length, length of tail up to switch, face length, face width, horn length, circumference of horn at base, distances between pin bone and hip bone) were recorded in 233 adult Gojri buffaloes from Punjab and Himachal Pradesh states of India. Traits were analysed by using varimax rotated principal component analysis (PCA) with Kaiser Normalization to explain body conformation. PCA revealed four components which explained about 70.9% of the total variation. First component described the general body conformation and explained 31.5% of total variation. It was represented by significant positive high loading of height at wither, body length, heart girth, face length and face width. The communality ranged from 0.83 (hip bone distance) to 0.45 (horn length) and unique factors ranged from 0.16 to 0.55 for all these 13 different biometric traits. Present study suggests that first principal component can be used in the evaluation and comparison of body conformation in buffaloes and thus provides an opportunity to distinguish between early and late maturing to adult, based on a small group of biometric traits to explain body conformation in adult buffaloes.