• Title/Summary/Keyword: mating age

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Genetic Parameters for Litter Size in Pigs Using a Random Regression Model

  • Lukovic, Z.;Uremovic, M.;Konjacic, M.;Uremovic, Z.;Vincek, D.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.2
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    • pp.160-165
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    • 2007
  • Dispersion parameters for the number of piglets born alive were estimated using a repeatability and random regression model. Six sow breeds/lines were included in the analysis: Swedish Landrace, Large White and both crossbred lines between them, German Landrace and their cross with Large White. Fixed part of the model included sow genotype, mating season as month-year interaction, parity and weaning to conception interval as class effects. The age at farrowing was modelled as a quadratic regression nested within parity. The previous lactation length was fitted as a linear regression. Random regressions for parity on Legendre polynomials were included for direct additive genetic, permanent environmental, and common litter environmental effects. Orthogonal Legendre polynomials from the linear to the cubic power were fitted. In the repeatability model estimate of heritability was 0.07, permanent environmental effect as ratio was 0.04, and common litter environmental effect as ratio was 0.01. Estimates of genetic parameters with the random regression model were generally higher than in the repeatability model, except for the common litter environmental effect. Estimates of heritability ranged from 0.06 to 0.10. Permanent environmental effect as a ratio increased along a trajectory from 0.03 to 0.11. Magnitudes of common litter effect were small (around 0.01). The eigenvalues of covariance functions showed that between 7 and 8 % of genetic variability was explained by individual genetic curves of sows. This proportion was mainly covered by linear and quadratic coefficients. Results suggest that the random regression model could be used for genetic analysis of litter size.

Effects of Dietary Supplementation of Conjugated Linoleic Acid (CLA) on Piglets' Growth and Reproductive Performance in Sows

  • Park, J.C.;Kim, Y.H.;Jung, H.J.;Moon, H.K.;Kwon, O.S.;Lee, B.D.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.2
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    • pp.249-254
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    • 2005
  • The objective of this study was to investigate effects of dietary level of CLA and the duration of feeding CLAcontaining diets on reproductive performance in sows and piglet growth rate. Tallow (3% in gestation diet and 5% in lactation diet, respectively) was incorporated as a fat source in control diet, and each 50% (dietary CLA level of 0.75% in gestation diet, and 1.50% in lactation diet, respectively) or 100% (dietary CLA level of 1.50% in gestation diet, and 2.50% in lactation diet, respectively) of tallow was replaced by a commercial CLA preparation containing 50% CLA isomers. Diets containing CLA were fed either from d 15 premating to weaning or d 74 post-mating to weaning. The level of dietary CLA and feeding duration did not affect litter size. High dietary level of CLA, however, decreased piglet weights at birth (p<0.01) and tended to decrease backfat thickness of sows at weaning. Longterm feeding of CLA-containing diets decreased piglet weights at weaning (p<0.05) and backfat thickness of sows at weaning (p<0.05). CLA supplemented in sow diet was transferred to fetus and piglets during pregnancy and nursing period, respectively. CLA contents of femoral muscle of piglets were 2.08 to 2.57 mg per g of fat at birth, and 2.36 to 4.47 mg at 10 days of age in CLA groups, while CLA was not detected in the control group. In conclusion, dietary supplementation of CLA tended to lower backfat thickness of sow and piglets' weight at birth or weaning, but did not affect total litter size. Dietary CLA was transferred efficiently during prenatal and postnatal periods of time through the placenta and milk, respectively.

Introgression of Sex-Limited Larval Markings to a Productive Multivoltine Strain of Silkworm Bombyx mori L.

  • Rao, D. Raghavendra;Singh Ravindra;Basavaraja H.K.;Kariappa B.K.;Dandin S.B.;Rufaie S.Z. Haque
    • International Journal of Industrial Entomology and Biomaterials
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    • v.13 no.1
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    • pp.7-14
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    • 2006
  • A breeding programme was initiated during 2001 to introduce sex-limited larval markings to a productive multivoltine breed - BL67 from an inbred sex-limited line, MY1 (SL) maintained at Central Sericultural Research and Training Institute, Mysore. Introgressive hybridization, recurrent backcrossing for six generations followed by sib-mating resulted in synthesis of a new multivoltine silkworm breed BL67 (SL) with sex-limited larval markings. The new breed was studied for combining ability by crossing with eight bivoltine breeds viz., $NB_4D_2,\;CSR_2,\;CSR_2 (SL),\;CSR_2,\;CSR_4,\;CSR_8,\;CSR_{18}\;and\;CSR_{19}$. General combining ability effects of the new breed showed its superiority over the popular Pure Mysore by expressing significant GCA effects for six out of twelve characters whereas the results are on par with the original multivoltine breed. The hybrid $BL67(SL){\times}CSR2(SL)$ excelled in several quantitative characters such as pupation rate (90.2%), cocoon weight (1.97 g), cocoon shell weight (40 cg), cocoon shell ratio (20.3%), filament length (918 m), denier (2.96), raw silk percentage (14.96%) and neatness (90 p). Studies on cocoon size variability revealed that the cocoons of $BL67(SL){\times}CSR2(SL)$ were found comparatively uniform showing less standard deviation of 6.55 and co-efficient of variation of 3.91 %. The suitability of newly developed breed for easy grain age operation and commercial exploitation with promising hybrid have been discussed.

Effects of Maternal Folic Acid Nutritional Status on the Expression of Myelin Basic Protein in the Offspring (어미 쥐의 엽산 영양상태가 자손 쥐의 수초기본단백질(Myelin Basic Protein)발현에 미치는 영향)

  • Chae, Eun-Hye;Kim, Soo-Jung;Lee, Hwa-Young;Chang, Nam-Soo
    • Journal of Nutrition and Health
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    • v.40 no.2
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    • pp.130-137
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    • 2007
  • Myelin basic protein (MBP), a major structural protein of the myelin, is thought to be important for the maintenance of myelin in the central nervous system (CNS). We investigated the effect of maternal folic acid nutritional status on the folate level and the synthesis of MBP in the offspring. In order to test this hypothesis, female Sprague-Dawley rats were fed either folic acid sufficient (8 mg/kg diet) or deficient (0 mg/kg diet) diet from 2 wks prior to the mating throughout the entire pregnancy, lactation and weaning period. We examined plasma folate level by the radioimmunoassay and homocysteine level by HPLC, respectively. The MBP expression was measured by the western blot analysis. The maternal folic acid deficiency decreased plasma folate level with a concomitant increase in plasma homocysteine level in their offspring. The maternal folic acid deficiency decreased hepatic levels of SAM and SAM/SAH ratio with a concomitant increase in hepatic levels of SAH and the MBP expression of spinal cord in their offspring at 7 wks of age. These results suggest that maternal folic acid nutritional status affect plasma folate and homocysteine level in their offspring. Moreover, the maternal folic acid deficiency mi호t inhibit the MBP expression of the spinal cord and disrupt many other vital CNS reactions in their offspring.

An Evaluation of Suckling and Post Weaning Practices in Relation to the Stimulation and Ease of Detection of Oestrus in Nepalese Pakhribas Pigs

  • Shrestha, NP;Edwards, S.A.;English, P.R;Robertson, J.F.
    • Asian-Australasian Journal of Animal Sciences
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    • v.14 no.6
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    • pp.765-770
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    • 2001
  • Thirty second parity sows of the synthetic Nepalese Pakhribas genotype were used to investigate factors which might improve the occurrence and expression of estrus. The experiment had two sequential elements. In part 1, a change in suckling pattern was applied during lactation, and in part 2, different estrus detection methods were evaluated after weaning. All sows received the same pattern of weaning, which imitated the progressive weaning system used in Nepalese villages. Piglets from each litter were weaned at three ages (6, 7 and 8 weeks of age) in the proportion of 0.5 at 6 weeks followed by 0.25 at each of the subsequent weanings. In the first lactation treatment, the suckling pattern was left undisturbed, similar to the practice used in the villages in which the remaining piglets after first weaning are allowed continuous suckling. In the other treatment, the remaining piglets after first weaning were allowed to suckle their sows only during the night, whilst in the day time (09:00-16:00) they were excluded from the sow but left free to roam around. After weaning, estrus detection procedures were carried out in the absence or presence of two different boar stimuli: a synthetic boar pheromone spray or fresh boar urine. These were applied sequentially in a sequence of testing that alternated for each sow on a daily basis. The weaning to re-mating interval was significantly longer for the unrestricted suckling treatment. All sows were re-mated within 30 days after first weaning in the restricted suckling treatment groups, whereas only 71% of sows were re-mated within 30 days after weaning in the unrestricted suckling treatment groups ($x^2=3.877$, 1df, p<0.05). Both boar pheromone spray and boar urine increased the estrus detection probability, with no significant differences between the two stimuli treatments.

Preservation of Acid Treated Bivoltine Eggs in Silkworm Bombyx mori L.

  • Rajanna, K. L.;Raju, P.Jayarama;Prabhakar, C.J.;Kamble, C.K.
    • International Journal of Industrial Entomology and Biomaterials
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    • v.17 no.2
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    • pp.165-168
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    • 2008
  • The hybrid ($CSR2{\times}CSR4$) eggs treated with acid were taken up for the study with an objective to develop long-term preservation schedule. The hybrid eggs obtained with two mating duration (3 h and 6 h) and oviposition period (6 h and 24 h) with two age groups of eggs (24 h and 36 h) were treated with Hydrochloric acid. These eggs were subjected to preservation at $5^{\circ}C$ in single step refrigeration and at $5^{\circ}C$ and $2.5^{\circ}C$ under double step refrigeration from $10{\sim}120$ days. These eggs were released from the cold storage as per the specified durations and incubated at standard conditions and allowed 2 h for hatching at 450 lux light. Hatchability was found to be significantly higher or on par with the control in three treatments (T1, T2 and T4) where the eggs are preserved continuously at $5^{\circ}C$ up to 30 days. However under double step refrigeration, hatching was not significantly affected in 20+60 day's combination of T1 treatment up to 80 days. Bioassay studies of the promising treatment i.e.. T1 with (20+60) days indicated that early stage loss and cocoon yield was found to be on par with the control. Hence this treatment was recommended for preservation of acid treated new bivoltine hybrid layings. Details of the hatchability and rearing performance of long term preservation of acid treated eggs are discussed.

The Influence of Dam Weight, Body Condition and Udder Scores on Calf Birth Weight and Preweaning Growth Rates in Beef Cattle

  • Paputungan, U.;Makarechian, M.
    • Asian-Australasian Journal of Animal Sciences
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    • v.13 no.4
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    • pp.435-439
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    • 2000
  • Records of weight, age, body condition at calving and udder characteristics scores of 425 beef cows and birth weights and periodical weights of their offspring from birth to weaning were analyzed to study the effect of body weight, condition and udder characteristic scores of dams on birth weight and Preweaning growth of their offspring. Dam's body condition (fat reserve) at calving were scored on a scale of 1 to 5 (1=extremely thin and 5=extremely fat) and dam's udder characteristics were scored on a scale of 1 to 7 (l=udder well attached with small teats and 7=at least one quarters not functional). Dams were from three distinct breed groups and were mated in single sire mating groups within each breed group for 45 days. Within each breed group and year, the dams were classified into high, medium and low based on their weights at the time of parturition. The data were analysed using covariance analysis. In general, calves born to heavier dams were heavier at birth and had higher rate of Preweaning growth. The effect of dam's body condition score on the calf birth weight was not significant. However, cows with average body condition score of 2.5 or 3.0 gave birth to calves that had higher pre weaning growth rates up to weaning than those born to calves with higher body condition score. The udder characteristics score did not affect calf birth weight as expected; however, cows with udder score of 3 (udder well attached with large teats) produced calves with higher preweaning growth rate than those with smaller teats. Based on the results, it can be concluded that maintaining animals with average body condition and weight would result in more efficient calf production. In addition, cows with well attached udder and large teats would provide a better maternal environment for Preweaning growth rates of their calves.

The Yield and Composition of Milk from Transgenic Rabbits

  • Chrenek, P.;Chrastinova, L.;Kirchnerova, K.;Makarevich, A.V.;Foltys, V.
    • Asian-Australasian Journal of Animal Sciences
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    • v.20 no.4
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    • pp.482-486
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    • 2007
  • Basic objective of this research was to compare the milk yield and composition of New Zealand White transgenic rabbit females expressing recombinant human factor VIII (hFVIII) in mammary gland during lactation with that of non-transgenic rabbit females of the same age during 30 days of lactation. Transgenic founders were generated by the microinjection of foreign DNA (mWAP-hFVIII gene construct) into the egg. F1, F2 and F3 generations of transgenic rabbits were obtained after mating of transgenic founder rabbits with non-transgenic rabbits. The amount of milk rejected was measured by weight-suckle-weight method at $10^{th}$, $20^{th}$and $30^{th}$ day of lactation. Quality of milk (content of fat, protein, lactose, dry ash, and some minerals) from transgenic and non-transgenic rabbit was also determined. Comparison of milk yield, determined by weight-suckle-weight method, showed significantly higher (p<0.05) milk production at day 20 of first lactation in non-transgenic females, but on the same day of second lactation higher milk yield was measured in transgenic ones. Significantly higher (p<0.05) content of milk fat and protein was determined in transgenic milk whilst higher content of lactose was found in non-transgenic milk. The content of minerals (calcium, phosphorus, magnesium and sodium) did not differ in both experimental and control groups. Our results showed that milk yield and composition of transgenic rabbit females (mammary specific transgenic over-expression of hFVIII) over several generations is only slightly and transiently different from milk yield of non-transgenic females, which had no significant consequence on the litter size and viability.

A Discriminant Analysis Study on Selection of Delivery Place and Delivery Attendants in Korean Rural Remote Area (판별분석 기법을 이용한 농촌지역 산모의 분만장소 및 분만 개조자 선정에 관한 연구)

  • 한경애
    • Journal of Korean Academy of Nursing
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    • v.16 no.2
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    • pp.44-52
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    • 1986
  • Maternal and child health(MCH) status is considered as an important indicator of the level of health and civilization of a community and a country. MCH services for the rural population in the remote ar deserves priority by the government, since more than half(52.9%) of the delivery was occured at home and almost half (45.5%) of the delivery was assited by family members or neighbors. The purpose of the study was to analyse the health fare behavior related to pregnancy and delivery, which can be contributed maternal health care policy mating for the rural people. Specifically, it was intended to analyze the variables which affect the health care behavior in selecting birth places and birth attendants. This study utilized the data which had been already collected for an experimental study on primary health program model in Korean rural communities, funded by the USAID. 184 sample households with women who had delivered a baby during March 1982 to February 1983 were selected. Discriminant Analysis was employed for statistical analysis by utilizing SPSS computer package program. Birth places and birth attendants were considered as dependent variables. Among 12 independent variables in 5 groups considered, 7 independent variables were found statistically significant to affect the selection of birth place. Significant variables by the order of importance are mother's age, order of baby, number of prenatal care, accessibility of emergency medical care, coverage of medical insurance, mother's membership in community organization and husband's educational level. The degree of correct classification of the grouped cases by employing a discriminant . analysis was significantly improved to 78.2% in comparison to Cmax(56%) and Cpro(51%). Policy implications for each significant variable were discussed to improve the maternal and child health. in Korean ruralarea.

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Comparison of Egg Production among Crossbreds with Resistance to Fowl Typhoid in Egg Type Chickens (산란계에 있어서 가금티푸스 저항성 계통의 산란성 비교 연구)

  • 오봉국;한성욱;김기석;한경택
    • Korean Journal of Poultry Science
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    • v.30 no.1
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    • pp.1-10
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    • 2003
  • The objects of this study were to develop a new strain which has resistance to fowl typhoid, high performance in laying, and producing brown shell eggs favored by domestic consumers. Several White Leghorn (WL) breeds known as possessing genetic resistance to fowl typhoid and several brown shell egg breeds such as susceptible to the disease were used to produce the controlled strains with cross mating between the strains within the breeds and the experimental strains with crossbreeding between the breeds. The crossbred strains were Chungnong(CN) 21, 22, 23, 24, 25 and 26. The controlled strains were ISA brown CC, Hyline brown CC and Lohman brown CC. The survival rates were 99.95% for chicks of age 0∼l7 weeks and 91% for adult chickens of age 18∼72 weeks. There was no difference in survival rate between the crossbred and the controlled strains. The means of age of lst egg laying were 147 to 148 days and no difference was observed between the crossbred and the controlled. The egg Production rates of a9e 18∼72 weeks were 83.76% far the crossbred strains and 77.82% for the controlled strains, which is significantly higher in the crossbred than controlled strains by 6%. The numbers of the hen housed egg Production of age 18∼72 weeks were 292.33 eggs for the crossbred strains and 271.31 eggs fur the controlled strains. The difference of 21 eggs more produced by the crossbred than by the controlled was statistically significant. The mean egg weights of age 18∼72 weeks were 64.32g for the crossbred strains and 60.73g for the controlled strains, and the difference of 3.59g was statistically significant. The feed conversion rates during the age of 18 to 72 weeks were 2.297 for the crossbred strains and 2.454 for the controlled strains. The crossbreds were reduced feed consumption by 157g for 1kg of egg Production which was statistically significant. Haugh unit(H$.$u) at the age of 72 weeks were 82.20 for the crossbred strains and 77.82 for the controlled strains. The crossbred strains were superior quality by 4.38 H$.$u. There were no significant differences in the yolk color and the eggshell thickness between the crossbred strains and the controlled strains. The eggshell color of the crossbred strains was light brown which is the medium color of the white eggshell strains and the brown eggshell strains. The body weights at the ages of 8, 12, 18, 42 and 71 weeks were not different between the crossbred strains and the controlled strains.