• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.10
• /
• pp.1573-1578
• /
• 2020

Objective: Milk fatty acid (FA) is a main nutritional component that markedly effects human health. Intentional modification of the FA profile has the potential to improve milk quality. This study aimed at the factors affecting elevated FA levels and the estimation of the genetic parameters for milk FAs in the Korean Holstein population. Methods: Total 885,249 repeated test-day milk records including, milk yield, saturated fatty acids (SFA), polyunsaturated fatty acids (PUFA), monounsaturated fatty acids (MUFA), total unsaturated fatty acids (TUFA), fat and protein percentages were analyzed using CombiFoss FT+ system (Foss Analytical A/S, Denmark). Genetic parameters were estimated by the restricted maximum likelihood procedure based on the repeatability model using the Wombat program. Results: The FA profile varies along with the lactation and the energy balance (EB). With the negative EB in early lactation, mobilization of body fat reserves elevates the desirable FA levels. As a result of that, milk quality is increased by means of nutritionally and usability aspects during the early lactation. Moreover, heritability estimates for SFA, MUFA, PUFA, TUFA were 0.33, 0.42, 0.37, 0.41 respectively. According to the parity wise heritability analysis, first parity cows had relatively lower heritability for SFAs (0.19) than later parities (0.28). Conclusion: Genetic parameters indicated that FAs were under stronger genetic control. Therefore, we suggest implementing animal breeding programs towards improving the milk FA profile.

• Journal of Animal Science and Technology
• /
• v.48 no.1
• /
• pp.39-48
• /
• 2006

This study utilized test day of somatic cell score data of dairy cattle from 2000 to 2004. The number of data used were 124,635 of first parity, 134,308 of second parity, 77,862 of third parity, 41,787 of forth parity and 37,412 of fifth parity. The data was analyzed by least square mean method using GLM to estimate the effects of calving year, age, lactation stage, parity and season on somatic cell score. Variance component estimation using test day model was determined by using expectation maximization algorithm- restricted maximum likelihood (EM-REML) analysis method. In each parity, somatic cell score was low for younger group and was relatively high in older groups. Likewise, for lactation stage, the score was low in early-lactation and high in late-lactation in first parity and second parity. Nevertheless, for the third, fourth and fifth parity, however, high somatic cell score was observed in mid-lactation. Generally, the score was high in the peak. Although in fourth and fifth parity, the score was low in late-lactation. Environmental effect of season, somatic cell score was generally low from September to November for all parities. The score was high between June and August when the milk production is usually low. The heritability in each parity were 0.05, 0.09, 0.10, 0.05 and 0.05 for parity 1, 2, 3, 4, 5, respectively. Genetic variance value was estimated to be high in second, third and fifth parity in early-lactation and to be low in first and forth parity.

• Asian-Australasian Journal of Animal Sciences
• /
• v.15 no.10
• /
• pp.1453-1457
• /
• 2002

The experiment was conducted to find out the effect of 4 feeding systems on growth, feed intake, eating behavior, lactation performance, gestation period, post-partum heat period, conception rate and parasitic infestation of Black Bengal goat. Twenty four does of approximately 1 year of age were randomly selected for 4 treatment (feeding systems) groups having 6 replications in each. Treatments were stall feeding ($T_1$), tethering ($T_2$), restricted grazing ($T_3$) and grazing ($T_4$). $T_1$ group was housed continuously and adequate amounts of natural grass were supplied for ad libitum feeding. $T_2$ group was tethered for grazing natural grass from 8 a.m. to 4 p.m. being moved at one hour intervals. Goats of $T_3$ group were allowed grazing from 8 a.m. to 1 p.m. $T_4$ group was grazed from 8 a. m. to 4 p.m. Concentrate supplement was given at the rate of 150 g per day per goat for all of the treatment groups. Duration of experiment was 219 days. Daily live weight gain was significantly (p<0.05) higher in case of stall fed goats than that of others. DM intake also significantly (p<0.05) differed among the treatment groups and was 3.40 3.95, 3.76 and 4.05 per cent of their live weight for stall feeding, tethering, restricted grazing and grazing groups, respectively. Rate of rumination was significantly (p<0.05) higher in case of tethering group of goats than that of others. Birth weight of kids, milk yield, lactation period and post-partum heat period were significantly higher in case of stall fed goats than others. Tethering group showed significantly (p<0.05) higher litter size than others. Infestation rate of Fasciola was significantly (p<0.05) higher in the grazing group. In conclusion, it may be stated that among these feeding groups overall performance of stall fed goats was more satisfactory, and that the tethering group showed better performance than the others.

• Asian-Australasian Journal of Animal Sciences
• /
• v.19 no.9
• /
• pp.1225-1228
• /
• 2006

A total of 1,367 first lactation records of daughters of 81 sires, having 5 or more progeny were used to evaluate sires by 3 different methods viz., least squares (LS), best linear unbiased prediction (BLUP) and derivative free restricted maximum likelihood (DFREML) method. The highest and lowest overall average breeding value of sires for first lactation 305 days or less milk yield was obtained by BLUP (1,520.72 kg) and LS method (1,502.22 kg), respectively. The accuracy, efficiency and stability of different sire evaluation methods were compared to judge their effectiveness. The error variance of DFREML method was lowest ($191,112kg^2$) and its coefficient of determination of fitting the model was highest (33.39%) revealing that this method of sire evaluation was most efficient and accurate as compared to other methods. However, the BLUP method was most stable amongst all the methods having coefficient of variation (%) very near to unadjusted data (18.72% versus 19.89%). The higher rank correlations (0.7979 to 0.9568) between different sire evaluation methods indicated that there was higher degree of similarity of ranking sires by different methods ranging from about 80 to 96 percent. However, the DFREML method seemed to be the most effective sire evaluation method as compared to other methods for the present set of data.

• Asian-Australasian Journal of Animal Sciences
• /
• v.13 no.10
• /
• pp.1347-1352
• /
• 2000

The objectives of the study were to examine non-genetic factors that influence somatic cell counts in dairy cattle and to estimate the genetic parameters of somatic cell counts. A total of 34, 097-test day somatic cell count records were obtained from the Zimbabwe Dairy Services Association (ZDSA). The data were from 5, 615 Holstein daughters of 390 sires and 2, 541 dams tested between May 1994 and December 1998. First lactation cows contributed 22, 147 records to the data set, while 11, 950 records were from second and later parity cows. The model for analysis included fixed effects of month of calving, year of calving, stage of lactation, calving interval and test date. Milk yield and age on test day were fitted in the model as covariates. The additive genetic effects pertaining to cows, sires and dams and the residual error were the random effects. The Average Information Restricted Maximum Likelihood algorithm was used for analysis. The heritability of somatic cell scores was low at $0.027{\pm}0.013$ for parity one cows and $0.087{\pm}0.031$ for parity two and above. Repeatability estimates were $0.22{\pm}0.01$ and $0.30{\pm}0.01$ for the two lactation groups, respectively. Genetic and phenotypic correlations between the somatic cell scores and test day milk production were small and negative. It seems that there is no genetic link between somatic cell counts and milk yield in Holstein cattle in Zimbabwe. The results also seem to indicate that somatic cell count is a trait that is mainly governed by environmental factors.

• Asian-Australasian Journal of Animal Sciences
• /
• v.3 no.2
• /
• pp.125-133
• /
• 1990

The effect of dietary protein-energy restriction (PER) on the growth of long bone were examined in sheep during growing period and then following a cycle of reproduction. Three months-old female sheep were offered protein-energy restricted feed for 6 months (growing period), thereafter changed to normal nutritional conditions for 8 months (reproduction period). A half of animals in each group took pregnancy, parturition and lactation. The nutritional restriction reduced the growth in bone diameter more than that in bone length. Compensatory growth resulting from the removal of the nutritional restraint strongly occurred in bone diameter, especially the bone cortical width, as compared to bone longitudinal growth. A cycle of reproduction severely decreased the growth in the bone cortical width relative to that in the bone width, and little effect was found on the growth in bone length and bone mass. The depression of bone development by pregnancy and lactation tended to exhibit severer in animals having received normal nutrition than in those having received PER. Bone mineral density was not affected by the nutritional restriction. A cycle of reproduction had an adverse effect on the mineral density between in animals having received normal nutrition and in those having received PER.

• 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.

• Clinical and Experimental Pediatrics
• /
• v.60 no.3
• /
• pp.70-76
• /
• 2017

Purpose: This study investigated self-food restriction during breastfeeding, reviewed the literature showing the effect of maternal diet on the health of breast-fed infants, and explored the validity of dietary restrictions. Methods: Questionnaire data were collected from breastfeeding Korean mothers who visited the pediatric clinic of Cheil General Hospital & Women's Healthcare Center from July 2015 through August 2015. The survey included items assessing maternal age, number of children, maternal educational attainment, household income, degree of difficulty with self-food restriction, types of self-restricted foods, dietary customs during breastfeeding, and sources of information about breastfeeding. Results: The questionnaire was completed by 145 mothers. More than a third (n=56, 39%) had discomfort from and usually avoided 4-5 types of food (mean, 4.92). Mothers younger than 40 years had more discomfort (odds ratio [OR], 12.762; P=0.017). Primiparas felt less discomfort than multiparas (OR, 0.436; P=0.036). Dietary practices were not influenced by maternal educational attainment or household income. The most common self-restricted foods were caffeine (n=131, 90.3%), spicy foods (n=124, 85.5%), raw foods (n=109, 75.2%), cold foods (n=100, 69%), and sikhye (traditional sweet Korean rice beverage) (n=100, 69%). Most mothers (n=122, 84.1%) avoided foods for vague reasons. Conclusion: Most mothers restricted certain foods unnecessarily. Literature review identified no foods that mothers should absolutely avoid during breastfeeding unless the infant reacts negatively to the food.

• Asian-Australasian Journal of Animal Sciences
• /
• v.33 no.2
• /
• pp.236-244
• /
• 2020

Objective: The objective of this study was to evaluate the effects of different levels of quantitative feed restriction on nutrient intake and digestibility, nitrogen balance, efficiency and feeding behavior, and productive performance in F1 Holstein/Zebu cows during the middle third of their lactation. Methods: Sixty F1 Holstein/Zebu cows with 111.5±11.75 days of lactation and an initial body weight (BW) of 499±30 kg (mean±standard error of the mean) were used. The experimental design was completely randomized with the following diet levels of feed restriction: 3.39%, 2.75%, 2.50%, 2.25%, and 2.00% of BW, with 12 replications for each level. The experiment lasted for 63 days, of which each period lasted 21 days with the first 16 days for diet adaptation followed by 5 days for collection of data and samples. Results: For each 1% of BW diet restriction, there was a decrease in dry matter intake of 5.26 kg/d (p<0.01). There was no difference in daily milk production (p = 0.09) under the restriction levels of 3.39% to 2.0% of BW. When corrected for 3.5% fat, milk production declined (p = 0.05) 3.46 kg/d for each percentage unit of feed restriction. Conclusion: Restricting the feed supply for F1 Holstein/Zebu cows in the middle third of their lactation period altered nutrient intake, nitrogen balance and ingestive behavior but did not affect milk production or feed efficiency. However, considering the observed BW loss and decrease in milk production corrected for 3.5% fat, restriction of no less than 2.5% BW is recommended.

• Asian-Australasian Journal of Animal Sciences
• /
• v.20 no.3
• /
• pp.340-350
• /
• 2007

The objective of this study was to determine whether peroxisome proliferator-activated receptor ${\gamma}$(PPAR${\gamma}$ is involved in the regulation of weaning to estrus of primiparous sows. Twelve sows composed of 6 groups of 2 full-sibs in a similar age (325.2 d), body weight (BW; 152.4 kg) and backfat thickness (BFT; 27.0 mm) at start of lactation, were allocated to accept 31 MJ (restricted group, R-group) or 53 MJ (control group, C-group) DE/d treatment, respectively. The experimental results indicated that the low energy intake resulted in excessive losses of BW and BFT during lactation in R-group sows, which may be related to decrease of serum 15-deoxy-${\Delta}^{12,14}$-prostaglandin $J_2$ (15d-$PGJ_2$), a ligand of PPAR${\gamma}$ The obvious peak and the frequency of LH, FSH and estradiol ($E_2$) were only observed in C-group sows. Except for $E_2$ at d 1 and 2, serum FSH, LH and $E_2$ concentrations in R-group were lower than those in C-group sows after weaning. However, the serum progesterone ($P_4$) level in R-group sows was always more than that in C-group. The expression abundances of PPAR${\gamma}$and GnRH receptor (GnRH-R) in pituitary, FSH receptor (FSH-R), LH receptor (LH-R), estrogen receptor (ES-R) and aromatase in ovary of anestrous sows were lower than those of estrous sows. Neither the BFT nor the BW was associated with the mRNA abundance of PPAR${\gamma}$in hypothalamus during lactation. Expressions of PPAR${\gamma}$in pituitary and ovary were affected evidently by the BFT changes and only by the loss of BW of sows during and after lactation. Furthermore, PPAR${\gamma}$mRNA level in ovary was significantly related to the expression abundances of GnRH-R, FSH-R, ES-R and aromatase, and GnRH-R was obviously associated with PPAR${\gamma}$expression in pituitary. However, PPAR${\gamma}$expression in hypothalamus likely has no effects on these genes expression and no obvious difference for all sows. Not serum $E_2$ or $P_4$ alone but the ratios of $E_2$ to $P_4$ and 15d-$PGJ_2$ to $P_4$, and serum FSH and LH were evidently related to PPAR${\gamma}$expression in pituitary and ovary. It is concluded that PPAR${\gamma}$is associated with body conditions, reproduction hormones and their receptor expression, which affected the functions of pituitary and ovary and ultimately the estrus after weaning of primiparous sows.