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1.
Analyses of variance were computed for records on growth and body composition traits made in 1983 by 255 boars and gilts in selected and control lines of Durocs and Yorkshires and their reciprocal crossbreds. Previous selection over a period of several generations was mainly on an index of sow productivity including preweaning litter sizes and weight. Animals in the select lines were selected for high index values; animals in the control lines were selected to average near the mean index values of that year and line. Breeding animals in all four lines during that period were basically randomly selected with regard to growth rate or body composition traits. The same boars sired both purebred and crossbred litters in 1983. Traits analyzed were average daily gain (ADG) during a standard test period from 56 d of age to 90.7 kg and average backfat thickness (ABF) and longissimus muscle area (LMA) from ultrasonic scans at 90.7 kg. Crossbred pigs had greater (P less than .01) ADG than purebred pigs, but did not differ (P greater than .05) in ABF or LMA. Heterosis was 8.2% for ADG. Crossbreds with Yorkshire dams had thinner (P less than .01) ABF and larger (P less than .01) LMA than crossbreds with Duroc dams. Boars had greater (P less than .05) ADG, thinner (P less than .01) ABF and smaller (P less than .01) LMA than gilts. Correlations between 38 half-sib family averages of purebred and crossbred pigs of the same sex and the same sires were .07, .37 and .24 for ADG, ABF and LMA, respectively. Implications of the above and additional findings for swine breeding strategies are discussed. 相似文献
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Rátky J Brüssow KP Egerszegi I Torner H Schneider F Solti L Manabe N 《The Journal of reproduction and development》2005,51(4):427-432
Only a very small amount of physiological data is available about the low fertility (mean litter size is 5.7+/-0.8) of Hungarian native breed, Mangalica (M), sows. The aim of the present paper is to reveal the differences in preovulatory follicle development and intrafollicular oocyte maturation between M and Landrace (L) gilts, with special reference to the peri- and postovulatory secretion and peripheral concentrations of estradiol-17beta (E2), progesterone (P4), and luteinizing hormone (LH). The number of preovulatory follicles was 6.8+/-1.4 and 19.6+/-6.6 in M and L gilts, respectively. A lower degree of cumulus expansion and a lower percentage of mature oocytes (TI/M II) was noted in M. Higher LH and E2 peak levels, a longer E2 to LH peak interval, and lower embryo survival was confirmed. Interestingly, despite the lower number of corpora lutea, a higher peripheral blood level of P4 was shown in M than in L gilts. Both diminished follicular development and protracted oocyte maturation may be involved in low fecundity in M, and the present findings may explain these reproductive phenomena. 相似文献
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《Livestock Production Science》1992,30(1-2):99-113
The number of ova released (ovulation rate) by 516 Large White gilts born between 1986 and 1989 was recorded. The weight of the gilt at birth, weaning and time of ovulation rate measurement and her number of teats were also recorded. Parrowing data (number born alive and litter weight at birth) corresponding to the ovulation rate were recorded from 382 of the gilts, enabling calculation of prenatal survival (number born alive/ovulation rate). The data were analysed using univariate and multivariate restricted maximum likelihood (REML) techniques with an individual animal model. The additive genetic direct and maternal components of variance and the common family and residual environmental components of variance and the additive genetic and residual environmental covariances between traits were estimated. The univariate REML analyses showed that the additive genetic direct component was a significant source of variation for gilt weight at birth and weaning, teat number, ovulation rate on the left hand side, total ovulation rate and litter weight at birth. Common family environmental effects were significant sources of variation for gilt weights and teat number. The multivariate REML analyses indicated that the genetic correlations between total ovulation rate and ovulation rate from the left and right ovaries were close to unity, with an estimate of the heritability of total ovulation rate of 0.37±0.09. In the data from gilts that farrowed, the heritabilities of ovulation rate, number born alive and prenatal survival were 0.30±0.10, 0.09±0.06 and 0.00±0.00, respectively. The genetic correlation between ovulation rate and litter size was close to unity, suggesting that genetic variation in ovulation rate explains virtually all of the genetic variation in number born alive in the population of Large White gilts understudy. 相似文献
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Shinichiro Ogawa Ayane Konta Makoto Kimata Kazuo Ishii Yoshinobu Uemoto Masahiro Satoh 《Animal Science Journal》2019,90(1):23-28
Genetic parameters were estimated for six reproductive traits related to farrowing events in Landrace and Large White pigs; total number born (TNB), number born alive (NBA), number stillborn (NSB), total litter weight at birth (LWB), mean litter weight at birth (MWB), and gestation length (GL). We analyzed 62,534 farrowing records for 10,637 Landrace dams and 49,817 farrowing records for 8,649 Large White dams. Estimated heritabilities of TNB, NBA, NSB, LWB, MWB, and GL by single‐trait repeatability model analyses were 0.12, 0.12, 0.08, 0.18, 0.19, and 0.29, respectively, in Landrace, and 0.12, 0.10, 0.08, 0.18, 0.16, and 0.34, respectively, in Large White. Genetic correlation between NBA and NSB was unfavorable: 0.20 in Landrace and 0.33 in Large White. Genetic correlations of GL with the other five traits were weak: from ?0.18 with NSB to ?0.03 with NBA in Landrace, and from ?0.22 with NSB to ?0.07 with NBA in Large White. LWB had a highly favorable genetic correlation with NBA (0.74 in both breeds), indicating the possibility of using LWB for the genetic improvement of NBA. 相似文献
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J. Verner P. Humpolíek & A. Knoll 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2007,124(2):81-85
Summary Porcine myogenic differentiation genes ( MYOD ) family play a key role in growth and muscle development and are therefore considered as candidate genes for meat production traits. The objective of the study was to investigate the polymorphisms at four loci belonging to the MYOD genes family and analyse their associations with variation in meat production traits in Czech pig breeds. To verify the associations between the polymorphisms and the selected meat traits, altogether 254 pigs, including full- and half-sibs, of Large White and Landrace breeds were tested. The studied meat characteristics were weight of neck, loin, shoulder and ham, lean meat content (LMC), backfat thickness, intramuscular fat (IMF), remission, dry matter content and test daily gain. Statistically significant associations were observed between MYOG gene and fat and neck weight, and between MYF5 gene and IMF and LMC. High significant differences were observed between genotypes AA and AB of MYOD1 in IMF and between genotypes AB and BB of MYF5 in loin weight. 相似文献
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Sixty-four Large White x Landrace primiparous sows were utilized to evaluate the influence of feeding 6 vs 9 Mcal ME/d during gestation on reproductive performance. The sows remained on their respective gestation diets for four parities if they successfully farrowed, rebred and conceived. Sows fed 9 Mcal ME/d gained more weight (P less than .05) through the gestation period during parities 1 and 2 and were heavier (P less than .01) on d 110 of gestation for combined parities. Lactation weight loss was greater (P less than .05) for the sows fed 9 Mcal ME/d, resulting in similar weights at weaning. Ultrasonic backfat measurements were greater (P less than .01) on d 110 of gestation for sows fed 9 Mcal ME/d during parity 1 and remained higher (P less than .01) through the fourth-parity gestation. Although sow weaning weights were similar, sows receiving 6 Mcal ME/d scanned less backfat thickness. Gestation treatment significantly affected consumption of a common lactation diet provided ad libitum. Sows fed 6 Mcal ME/d during gestation consumed an average of 22 kg more feed (P less than .01) during lactation than those sows receiving 9 Mcal ME/d. Litter performance as measured by number and weights of pigs born alive and weaned was not altered (P greater than .10) by gestation energy intake. Days to return to estrus and the number of sows remaining in the study for four parities were similar (P greater than .10) between the two treatment groups. The number of farrowings for the four parities totaled 164, with 83 and 81 farrowings for the sows fed 6 and 9 Mcal ME/d, respectively.(ABSTRACT TRUNCATED AT 250 WORDS) 相似文献
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Genetic relationship of litter traits between farrowing and weaning in Landrace and Large White pigs
Shinichiro Ogawa Ayane Konta Makoto Kimata Kazuo Ishii Yoshinobu Uemoto Masahiro Satoh 《Animal Science Journal》2019,90(12):1510-1516
We estimated genetic parameters in Landrace and Large White pig populations for litter traits at farrowing (total number born, number born alive, number stillborn, total litter weight at birth (LWB), and mean litter weight at birth) and those at weaning (litter size at weaning (LSW), total litter weight at weaning (LWW), mean litter weight at weaning (MWW), and survival rate from farrowing to weaning). We analyzed 65,579 records at farrowing and 6,306 at weaning for Landrace, and 52,557 and 5,360, respectively, for Large White. Single‐trait and two‐trait repeatability animal models were exploited to estimate heritability and genetic correlation respectively. Heritability estimates of LSW were 0.09 for Landrace and 0.08 for Large White. Genetic correlations of LSW with MWW were –0.43 for Landrace and –0.24 for Large White. Genetic correlations of LSW with LWW and LWB ranged from 0.5 to 0.6. The genetic correlation of MWW with LWW was positive, but that with LWB was negligible. The results indicate that utilizing LWW or LWB could improve LSW efficiently, despite the antagonistic genetic correlation between LSW and MWW. 相似文献
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Records of on-test ADG of Large White gilts were analyzed to estimate variance components of direct and associative genetic effects. Models included the effects of contemporary group (farm-barn-batch), birth litter, pen group, and direct and associative additive genetic effects. The area of each pen was 14 m2. The additive genetic variance was a function of the number of competitors in a group, the additive relationships between the animal performing the record and its pen mates, and the additive relationships between pen mates. To partially account for differences in the number of pen mates, a covariable (qi = 1, 1/n, or 1/n(1/2)) was added to the associative genetic effect. There were 4,946 records from 2,409 litters and 362 pen groups. Pen group size ranged from 12 to 16 gilts. Analyses by REML converged very slowly. A grid search showed that the likelihood function was almost flat when the additive genetic associative effect was fitted. Estimates of direct and associative heritability were 0.15 and 0.03, respectively. Within the BLUPF90 family of programs, the mixed-model equations can be set up directly. For variance component estimation, simple programs (REMLF90 and GIBBSF90) worked without modifications, but more optimized programs did not. Estimates obtained using the three values of qi were similar. With the data structure available for this study and under an environment with relative low competition among animals, accurate estimation of associative genetic effects was not possible. Estimation of competitive effects with large pen size is difficult. The magnitude of competition effects may be larger in commercial populations, where housing is denser and food is limited. 相似文献
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Enio Mori DVM MSc Regina M. S. Mirandola BSc MS Renaide R. Ferreira BSc Jos V. Oliveira DVM Francisco Gacek DVM PhD Wilson R. Fernandes DVM PhD 《Journal of Equine Veterinary Science》2004,24(7):271-276
Thirteen hematologic measurements were performed on 38 healthy donkeys of the Brazilian breed (32 females and 6 males) aged 3 to 19 years. Mean ±SD (minimum-maximum) values were as follows: red blood cells (RBC) 6.82 ± 0.67 (5.46−8.17) × 106/μL; packed cell volume (PCV) 37.63 ± 2.76 (32.00−44.00) %; hemoglobin (Hb) 12.87 ± 0.98 (10.70−14.50) g/dL; mean corpuscular volume (MCV) 55.45 ± 4.06 (48.90−62.70) fL; mean corpuscular hemoglobin (MCH) 18.85 ± 1.14 (17.40−21.60) pg; mean corpuscular hemoglobin concentration 34.20 ± 1.24 (31.50−36.40) g/dL; white blood cells (WBC) 8.22 ± 1.49 (4.60−11.50) × 103/μL; bands 1.77 ± 2.00 (0.00−9.00) %; segmented neutrophils 41.18 ± 5.98 (30.50−53.20) %; lymphocytes 50.53 ± 6.25 (35.30−63.50) %; monocytes 1.57 ± 1.30 (0.00−4.60) %; eosinophils, 4.64 ± 2.17 (1.00−10.00) %; basophils 0.33 ± 0.58 (0.00−2.90) %. It was demonstrated that values of some blood parameters of the Brazilian donkey breed were similar to results obtained for other donkey breeds. The results of this study serve as reference ranges for donkey populations and can be useful for health control, which in turn helps in the diagnosis and prognosis of diseases.
Introduction
Blood examination has been performed for several reasons: as a screening procedure to assess general health; as an adjunct to patient's infection; and to evaluate the progress of certain disease states.[1] However, there are important differences in physiology, behavior, and management that influence the common diseases encountered in donkeys. Successful diagnosis and treatment often depend on recognizing these differences. [2] Unfortunately, a limited number of observations have been reported on the hematologic values for donkey breeds and populations and these studies are far from complete. [3, 4, 5, 6, 7, 8 and 9] Hematologic variation values for donkey breeds and populations should be associated with the age, sex, and the time of sampling in relation to exercise, geographic, and nutritional factors. Perhaps some of the variations observed among different authors were also associated with different techniques and methods. [4]Apart from the investigations by Perdigão de Oliveira et al,[3] Gacek et al, [10] and Mori et al, [11] we could find no published record of blood values of the Brazilian donkey breed. The aim of this investigation was to determine reference ranges for hematologic analyses in the Brazilian donkey breed to establish a baseline for further scientific and clinical use.Materials and methods
The material for the present study consisted of 38 adult donkeys of the Brazilian breed (32 females and 6 males), ranging between 3 and 19 years of age (mean ±SD: 8.3 ± 3.5 years), from the Estação Experimental de Colina do Instituto de Zootecnia da Secretaria de Agricultura do Estado de São Paulo, and kept under similar feeding and management conditions. All animals were apparently healthy, and they were handled carefully to reduce any possible effects of stress on the parameters analyzed.Blood samples were draw from the jugular vein into 5 mL evacuated glass tubes containing EDTA as anticoagulant. Blood smears were prepared immediately after being collected from whole blood and then were air-dried. The collected blood samples were immediately stored at 4°C and processed within 6 hours.RBC and WBC counts were performed using an electronic counter (Serono Baker). Hb concentration was determined by the cyanmethemoglobin method. PCV was determined after the blood had been transferred to microhematocrit tubes and centrifuged at 10,000 g for 5 minutes. MCV, mean corpuscular hemoglobin, and mean corpuscular hemoglobin concentration were calculated from PCV, Hb concentration, and RBC count.[1] Blood smears were stained with modified May-Grunwald Giemsa stain for determination of the differential WBC count. At least 200 WBCs were counted for differential WBC determinations.All analyses were performed within the Departamento de Clinica Médica da Faculdade de Medicina Veterinária e Zootecnia da Universidade de São Paulo.Data analysis was performed using a statistical software (Graph Pad InStat version 3.01, 32 bit for Windows 95/NT). Each parameter was tested for normality applying the Kolmogorov and Smirnov methods. The reference ranges for the hematologic analyses were given as mean ±SD and the interval from minimum and maximum values.Unpaired t-tests were used to determine the effect of sex (female versus male) on hematologic values, for data normally distributed. If data did not seem to be normally distributed, non-parametric tests (Mann-Whitney U test) were used. The level of statistical significance was set at P < .05.Results
Reference ranges of hematologic constituents of the blood of the Brazilian donkey breed determined in the current study are shown in Table 1 and Table 2. Most of the values had Gaussian distribution (P < .10). Only basophils did not seem to be normally distributed (P < .05). Comparisons of hematologic ranges of the Brazilian donkeys with other donkey breeds and populations are shown in Table 1 and Table 2. 相似文献14.
本研究以大白猪和长白猪为研究对象,以促红细胞生成素受体(erythropoietin receptor,EPOR)基因作为产仔性状的候选基因,采用PCR-SSCP方法来检测EPOR基因第4内含子C\T突变多态性,研究此位点多态性与猪繁殖性状之间的关联性。结果发现,在长白猪和大白猪中存在AA、AB和BB共3种基因型,在2个群体中处于中度多态。利用SAS 8.0软件采用最小二乘法拟合线性模型,将不同基因型与总产仔数(TNB)、产活仔数(NBA)和初生重(WB)进行了关联分析,结果表明,长白猪初产母猪BB基因型个体的WB显著高于AB、AA基因型个体(P<0.05);经产母猪BB基因型个体的TNB显著高于AB基因型个体(P<0.05);B等位基因对初产母猪TNB、NBA和WB均表现为正效应。大白猪初产母猪BB基因型个体的TNB、NBA和WB都高于AA型和AB型个体,但差异均不显著(P>0.05);经产母猪AB基因型个体的WB显著高于AA基因型个体(P<0.05);B等位基因对初产母猪TNB、NBA和WB都表现为正效应。 相似文献
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Genetic analysis for sow stayability at different parities in purebred Landrace and Large White pigs
Shinichiro Ogawa Makoto Kimata Kazuo Ishii Yoshinobu Uemoto Masahiro Satoh 《Animal Science Journal》2021,92(1):e13599
Genetic parameters for sow stayability were estimated from farrowing records of 10,295 Landrace sows and 8192 Large White sows. The record for sow stayability from parity k to parity k + 1 (k = 1, …, 6) was 0 when a sow had a farrowing record at parity k but not at parity k + 1, and 1 when a sow had both records. Heritability was estimated by using single-trait linear and threshold animal models. Genetic correlations among parities were estimated by using two-trait linear–linear and single-trait random regression linear animal models. Genetic correlations with litter traits at birth were estimated by using a two-trait linear–linear animal model. Heritability estimates by linear model analysis were low (0.065–0.119 in Landrace & 0.061–0.157 in Large White); those by threshold model analysis were higher (0.136–0.200 & 0.110–0.283). Genetic correlations among parities differed between breeds and models. Genetic correlation between sow stayability and number born alive was positive in many cases, implying that selection for number born alive does not reduce sow stayability. The results seem to be affected by decisions on culling made by farmers. 相似文献
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The objective of this study was to estimate direct and indirect selection potential for length of productive life and lifetime prolificacy in Finnish Large White and Landrace swine populations. To study the direct selection potential, the heritabilities of these traits were estimated. The genetic correlations of length of productive life and lifetime prolificacy with prolificacy traits and overall leg conformation were estimated to evaluate whether selection for these traits could indirectly improve measures of sow longevity. In addition, correlations between length of productive life, lifetime prolificacy, ADG, and backfat thickness were estimated. Records were used from Finnish purebred Landrace (n = 26,744) and Large White (n = 24,007) sows born on operations that perform on-farm production tests on all females. Heritabilities were estimated using both a survival analysis procedure and a linear model. Due to computational limitations, correlations were estimated with the linear model only. Estimated length of productive life heritabilities obtained from linear model analyses were less (0.05 to 0.10) than those obtained from survival analyses (0.16 to 0.19). This may be indicative of the superiority of survival analysis compared with linear model analysis methods when evaluating longevity or similar types of data. All the prolificacy traits were genetically correlated with length of productive life and lifetime prolificacy, and the correlations were greater than 0.13. These results indicate that selection for increased number of piglets weaned in the first litter and for short first farrowing interval is beneficial for sow longevity and also for sow's lifetime prolificacy. The genetic correlations between length of productive life and leg conformation score also were favorable (0.32 in Landrace and 0.17 in Large White). The heritability estimates indicate that survival analysis is likely the most appropriate method of evaluating longevity traits in swine. Because of computational problems, simultaneous analysis of linear traits and longevity is not currently possible. More research is needed to develop methods for multiple linear and survival trait analyses. 相似文献
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Sow longevity influences farm economy and can be considered an important indicator of animal welfare. Body features such as leg conformation can play a key role in sow longevity, although little is known about its effect on culling decisions. Within this context, longevity data from 587 Duroc, 239 Landrace, and 217 Large White sows were analyzed with special emphasis on the effect of leg conformation. Sow longevity was analyzed twice for each breed, testing the effect of a subjective overall score for leg conformation, or the presence or absence of 6 specific leg conformation defects. Each preliminary model also included a teat conformation score with 3 levels, farm or origin, backfat thickness at 6 mo of age, and 2 continuous sources of variation, namely the age at the first farrowing and the number of piglets born alive at each farrowing. Overall leg conformation score influenced (P < 0.01) sow longevity in Duroc, Landrace, and Large White sows, with a greater hazard ratio (HR) for poorly conformed sows (1.56, 2.16, and 1.79, respectively) than for well-conformed sows (0.32, 0.66, and 0.68, respectively). Abnormal hoof growth reduced survivability in Duroc (HR = 2.78; P < 0.001) and Landrace sows (HR = 1.88; P < 0.01); the presence of splayed feet (P < 0.05) or bumps and injuries (P < 0.001) increased the risk of culling in Duroc sows (HR = 2.08 and 3.57, respectively), whereas the incidence of straight pastern increased the HR in Large White sows (HR = 2.49; P < 0.01). In all 3 breeds, longevity decreased for plantigrade sows, with a greater HR in Duroc (HR = 3.38; P < 0.001) than in Landrace (HR = 1.53; P < 0.10) and Large White sows (HR = 1.73; P < 0.05). Teat conformation did not influence sow longevity (P > 0.10). Estimates of heritability for longevity in Duroc sows ranged from 0.05 to 0.07 depending on the algorithm applied. Leg conformation had a substantial effect on sow longevity, where an accurate removal of poorly leg-conformed candidate gilts before first mating could improve sow survival and reduce culling costs. These moderate estimates of heritability indicated that survivability of Duroc sows could be genetically improved by direct selection for leg conformation. 相似文献