排序方式: 共有10条查询结果,搜索用时 46 毫秒
1
1.
Genetic evaluation using random regression models with different covariance functions for test‐day milk yield in an admixture population of Thailand goats 下载免费PDF全文
Mongkol Thepparat Wuttigrai Boonkum Monchai Duangjinda Sornthep Tumwasorn Sansak Nakavisut Thumrong Thongchumroon 《Animal Science Journal》2015,86(7):655-660
The objectives of this study were to compare covariance functions (CF) and estimate the heritability of milk yield from test‐day records among exotic (Saanen, Anglo‐Nubian, Toggenburg and Alpine) and crossbred goats (Thai native and exotic breed), using a random regression model. A total of 1472 records of test‐day milk yield were used, collected from 112 does between 2003 and 2006. CF of the study were Wilmink function, second‐ and third‐order Legendre polynomials, and linear splines 4 knots located at 5, 25, 90 and 155 days in milk (SP25–90) and 5, 35, 95 and 155 of days in milk (SP35–95). Variance components were estimated by restricted maximum likelihood method (REML). Goodness of fit, Akaike information criterion (AIC), percentage of squared bias (PSB), mean square error (MSE), and empirical correlation (RHO) between the observed and predicted values were used to compare models. The results showed that CF had an impact on (co)variance estimation in random regression models (RRM). The RRM with splines 4 knots located at 5, 25, 90 and 155 of days in milk had the lowest AIC, PSB and MSE, and the highest RHO. The heritability estimated throughout lactation obtained with this model ranged from 0.13 to 0.23. 相似文献
2.
Effects of forage ensiling and ration fermentation on total mixed ration pH,ruminal fermentation and performance of growing Holstein‐Zebu cross steers 下载免费PDF全文
Watcharawit Meenongyai Virote Pattarajinda Alexander M. Stelzleni Jutarat Sethakul Monchai Duangjinda 《Animal Science Journal》2017,88(9):1372-1379
Our objective was to determine the effect of forage ensiling and ration fermentation on total mixed ration pH, ruminal fermentation and animal performance. Thirty Holstein‐Zebu cross steers were allotted to feeding treatments for 188 days in a randomized complete block design including: fresh grass‐total mixed ration (GTMR; pH 4.7), grass silage‐TMR (STMR; pH 4.0) and fermented‐TMR (FTMR; pH 3.5). Average daily gain for STMR was greatest during the first 3 months period; however, that for FTMR tended to be greater than GTMR during the second 3 months period (P < 0.10). During the second period dry matter intake for STMR was the greatest (P < 0.01), but feed conversion ratio (P < 0.01) and cost per gain (P < 0.01) were the least for FTMR. Protein digestibility tended (P < 0.10) to be greater for FTMR than STMR and fat digestibility was greater (P < 0.05) for GTMR and FTMR than STMR. FTMR had less (P < 0.01) ruminal NH3‐N content than STMR. Total volatile fatty acids post‐feeding was greatest for GTMR (P < 0.01). Ruminal proportions of acetic and butyric acids were greater for FTMR than GTMR (P < 0.05); in contrast, propionic acid was greater for GTMR (P < 0.05). Utilizing silage or total ration fermentation did not negatively impact on ruminal pH. STMR and FTMRs can be used to maintain performance of growing crossbred Holstein steers. 相似文献
3.
Genetic relationships of fertility traits with test‐day milk yield and fat‐to‐protein ratio in tropical smallholder dairy farms 下载免费PDF全文
Sayan Buaban Monchai Duangjinda Mitsuyoshi Suzuki Yutaka Masuda Jureeratn Sanpote Keigo Kuchida 《Animal Science Journal》2016,87(5):627-637
The test‐day milk fat‐to‐protein ratio (TD‐FPR) could serve as a measure of energy balance status and might be used as a criterion to improve metabolic stability and fertility through genetic selection. Therefore, genetic parameters for fertility traits, test‐day milk yield (TD‐MY) and TD‐FPR, as well as, their relationships during different stages of lactation, were estimated on data collected from 25 968 primiparous Thai dairy crossbred cows. Gibbs sampling algorithms were implemented to obtain (co)variance components using both univariate linear and threshold animal models and bivariate linear‐linear and linear‐threshold animal models with random regression. Average TD‐MY and TD‐FPR were 12.60 and 1.15. Heritability estimates for TD‐MY, TD‐FPR and selected fertility traits ranged from 0.31 to 0.58, 0.17 to 0.19 and 0.02 to 0.05, respectively. Genetic correlations among TD‐FPR and TD‐MY, TD‐FPR and fertility traits, and TD‐MY and fertility traits ranged from 0.05 to ‐0.44, from ‐0.98 to 0.98 and ‐0.22 to 0.79, respectively. Selection for lower TD‐FPR would decrease numbers of inseminations per conception and increase conception at first service and pregnancy within 90 days. In addition, cow selection based only on high milk production has strong effects to prolong days to first service, days open and calving interval. 相似文献
4.
Halal products are growing in consumer markets worldwide, and pork meat is classified as non-halal. Manufacturers of processed foods and products must ensure that their products follow Islamic dietary law because pork is prohibited for Muslims. Droplet digital polymerase chain reaction (PCR) (ddPCR) is a novel method for identifying pig species and quantifying pork products. This experiment aimed to investigate pork species and establish the proportion of pork in meat products using the mitochondrial cytochrome b gene (CYTB). The study found that the correlation coefficient between the meat weight and DNA concentration of pork was 0.997, and the correlation coefficient between the DNA concentration and the target DNA copy number of pork was 0.998. The accuracy of the ddPCR assay was verified using a sample of a known proportion of pork, and it was revealed that this method is highly precise in quantifying pork products. Nine products contained an undeclared meat proportion (90%). The limit of detection for pork was 0.0001 ng. The analysis indicated that the ddPCR assay has high accuracy and sensitivity for quantifying pork products. Therefore, the predictive model can be used in routine laboratories for quality assurance of halal food products. 相似文献
5.
Monchai Pumkaew Suparat Taengchaiyaphum Sorawit Powtongsook Wiboonluk Pungrasmi Kallaya Sritunyalucksana 《Journal of the World Aquaculture Society》2019,50(4):878-886
Acute hepatopancreatic necrosis disease (AHPND) causes massive mortality in shrimp ponds within the first month poststocking. The causative agent is a specific strain of Vibrio parahaemolyticus (VPAHPND) that has acquired the capability to produce virulent binary toxins called ToxA and ToxB. This study aims to test the effect of the addition of an autoinducer‐2‐containing cell‐free supernatant (CFS) from the mutant Vibrio harveyi (VH) on growth and toxin production of VPAHPND. The relative AI‐2‐like activity in CFS was detected by luminescence assay. The effect of CFS (5 and 9%) on growth and toxin production of VPAHPND was evaluated. Compared to the control culture (without CFS‐VH addition), the addition of either 5 or 9% CFS‐VH affected the growth at the initial stage of VPAHPND. Similar growth profiles of VPAHPND were found with the addition of CFS‐VH at both concentrations. Western blot analysis suggests that the addition of CFS‐VH affected the production of both toxins. ToxA could be detected at the early hour post‐CFS‐VH inoculation, whereas the high amount of ToxB was detected when 5% CFS‐VH was added. However, interfering with the AI‐2 function with furanone, the AI‐2 antagonist resulted in a slight delay in the production of both toxins. Results from this study will help to design a novel strategy to control AHPND in shrimp culture. 相似文献
6.
A total of 210 chicken samples, from seven strains, were genotyped using 20 microsatellite loci of which 16 are recommended
by the Food and Agriculture Organization. The genetic variability and divergence of four Thai indigenous strains and three
commercial lines were assessed to generate baseline information for conservation, promotion, and make sustainable utilization
of indigenous chicken resources in Thailand. A total of 227 alleles were distributed ranging from six (MCW 111) to 16 (MCW
183 and LEI 166) alleles per locus. The highest (0.81) and lowest (0.77) average of expected heterozygosities were observed
in indigenous chicken (Dang) and commercial layer (Isa Brown), respectively. All microsatellite loci were in the Hardy–Weinberg
equilibrium, except for MCW111 and ADL372 in the Isa Brown line. The subpopulation division coefficient (F
ST
) was strong with the value of 0.183 indicating the genetic differentiation among the studied groups. Four genetic clusters
were detected: the first group consisted of layers (Isa Brown and White Leghorn); the second group was broiler; the third
group consisted of non-black feather indigenous chicken (Chee, Dang, and Leung Hang Khoa); and the fourth group was black
feather indigenous chicken (Pradu Hang Dam). The results of this study also suggested that Pradu Hang Dam is suitable to be
developed as a meat type chicken due to lower genetic distance between Pradu Hang Dam and broiler. 相似文献
7.
Genetic associations between milk fat‐to‐protein ratio,milk production and fertility in the first two lactations of Thai Holsteins dairy cattle 下载免费PDF全文
Somsook Puangdee Monchai Duangjinda Wuttigrai Boonkum Suporn Katawatin Sayan Buaban Mongkol Thepparat 《Animal Science Journal》2017,88(5):723-730
The aims of this study were to estimate, simultaneously, the genetic parameters of test‐day milk fat‐to‐protein ratio (FPR), test‐day milk yield (MY), and days‐open (DO) in the first two lactations of Thai Holsteins. A total of 76 194 test‐day production records collected from 8874 cows with 8674 DO records between 2001 and 2011 from different lactations were treated as separated traits. The estimates of heritability for test‐day FPR in the first lactation showed an increasing trend, whereas the estimates in the second lactation showed a U‐shape trend. Genetic correlations for FPR‐DO and MY‐DO showed a decreasing trend along days in milk (DIM) in both lactations, whereas genetic correlations for FPR‐MY increased along DIM in the first lactation but decreased in the second lactation. Genetic correlations of FPR between consecutive DIM were moderate to high, which showed the effectiveness of simultaneous analyses. Selection of FPR in the early stage has no adverse effect on MY and DO for the first lactation but has a negative effect on MY and positive effect on DO for the second lactation. This study showed that genetic improvement of the energy balance using FPR, MY and DO with multi‐trait test day model could be applied in a Thailand dairy cattle breeding program. 相似文献
8.
Estimation of genetic parameters for heat stress,including dominance gene effects,on milk yield in Thai Holstein dairy cattle 下载免费PDF全文
Heat stress in tropical regions is a major cause that strongly negatively affects to milk production in dairy cattle. Genetic selection for dairy heat tolerance is powerful technique to improve genetic performance. Therefore, the current study aimed to estimate genetic parameters and investigate the threshold point of heat stress for milk yield. Data included 52 701 test‐day milk yield records for the first parity from 6247 Thai Holstein dairy cattle, covering the period 1990 to 2007. The random regression test day model with EM‐REML was used to estimate variance components, genetic parameters and milk production loss. A decline in milk production was found when temperature and humidity index (THI) exceeded a threshold of 74, also it was associated with the high percentage of Holstein genetics. All variance component estimates increased with THI. The estimate of heritability of test‐day milk yield was 0.231. Dominance variance as a proportion to additive variance (0.035) indicated that non‐additive effects might not be of concern for milk genetics studies in Thai Holstein cattle. Correlations between genetic and permanent environmental effects, for regular conditions and due to heat stress, were ? 0.223 and ? 0.521, respectively. The heritability and genetic correlations from this study show that simultaneous selection for milk production and heat tolerance is possible. 相似文献
9.
Software applications for providing comprehensive computing capabilities to problems related to mixed models in animal breeding 下载免费PDF全文
Monchai DAUNGJINDA 《华南农业大学学报》2005,26(Z1)
Recently,several computer packages havebeen developed to accomplish problems relatedto mixed model in animal breeding.Special soft-ware for estimation of variance components andprediction of genetic merits are basically neededfor genetic evaluation and selection program.Al-though there are some packages available on theinternet,however,most of them are commercialor unfriendly to be used.The lists of recent soft-ware available on the internet are shown in Tab.1.Most software is free license(mo… 相似文献
10.
Genetic analysis of the rates of conception using a longitudinal threshold model with random regression in dairy crossbreeding within a tropical environment 下载免费PDF全文
Sayan Buaban Keigo Kuchida Mitsuyoshi Suzuki Yutaka Masuda Wuttigrai Boonkum Monchai Duangjinda 《Animal Science Journal》2016,87(8):961-971
This study was designed to: (i) estimate genetic parameters and breeding values for conception rates (CR) using the repeatability threshold model (RP‐THM) and random regression threshold models (RR‐THM); and (ii) compare covariance functions for modeling the additive genetic (AG) and permanent environmental (PE) effects in the RR‐THM. The CR was defined as the outcome of an insemination. A data set of 130 592 first‐lactation insemination records of 55 789 Thai dairy cows, calving between 1996 and 2011, was used in the analyses. All models included fixed effects of year × month of insemination, breed × day in milk to insemination class and age at calving. The random effects consisted of herd × year interaction, service sire, PE, AG and residual. Variance components were estimated using a Bayesian method via Gibbs sampling. Heritability estimates of CR ranged from 0.032 to 0.067, 0.037 to 0.165 and 0.045 to 0.218 for RR‐THM with the second, third and fourth‐order of Legendre polynomials, respectively. The heritability estimated from RP‐THM was 0.056. Model comparisons based on goodness of fit, predictive abilities, predicted service results of animal, and pattern of genetic parameter estimates, indicated that the model which fit the desired outcome of insemination was the RR‐THM with two regression coefficients. 相似文献
1