Litter size at lambing influences genetic evaluation of maternal rearing ability

2018 ◽  
Vol 58 (5) ◽  
pp. 791
Author(s):  
Kim L. Bunter ◽  
Andrew A. Swan ◽  
Daniel J. Brown ◽  
Forbes D. Brien ◽  
Jennifer Smith
Keyword(s):  
Litter Size ◽  
Genetic Correlations ◽  
Genetic Evaluation ◽  
Size Class ◽  
Industry Data ◽  
Common Mean ◽  
Mean And Variance ◽  
Highly Correlated ◽  
Change In Mean

The genetic parameters for maternal rearing-ability of ewes were investigated by ignoring or defining the rearing ability trait separately by litter-size class (singles versus multiples) using multi-generational data from three, fully pedigreed Merino flocks differing in prolificacy, production level and environment. Genetic correlations (ra) between litter size (LSIZE) and the percentage of lambs surviving (PLSURV) were more negative with an increasing mean flock litter size (ra: –0.21 ± 0.17 to –0.73 ± 0.08), while the corresponding range in phenotypic correlations (rp) was substantially lower (rp: –0.15 ± 0.01 to –0.33 ± 0.01). Rearing-ability traits defined separately by litter-size class were highly correlated (ra: 0.49 ± 0.19 to 0.64 ± 0.38), but not genetically identical traits in the most prolific flock. Defining rearing-ability traits separately by litter-size class reduced the antagonistic genetic correlations between LSIZE and PLSURV to between –0.39 ± 0.14 and 0.14 ± 0.28, through accommodating the change in mean and variance of PLSURV with LSIZE. Similarly, linear transformation (TSURV) of PLSURV within each litter size to a common mean and variance reduced the antagonistic trend in genetic correlations between LSIZE and TSURV to range between –0.05 ± 0.17 and –0.43 ± 0.13. Since genetic correlations are low to moderate between TSURV and LSIZE, it is possible to select for improvements in both the number of lambs born and lamb survival simultaneously. Defining rearing-ability traits separately by litter-size class and the role of transformation will be investigated further for improving the accuracy of genetic evaluation for rearing ability across a range of flocks, breeds and environmental conditions using more extensive industry data.

Modification of Teratogenic Action of Cortisone in Mice by Maternal Age, Maternal Weight and Litter Size

1956 ◽  
Vol 185 (1) ◽  
pp. 65-68 ◽  
Author(s):  
Harold Kalter
Keyword(s):  
Cleft Palate ◽  
Litter Size ◽  
Maternal Age ◽  
Fat Metabolism ◽  
Maternal Weight ◽  
Hybrid Female ◽  
Teratogenic Action ◽  
Median Cleft ◽  
Highly Correlated

Primigravid, hybrid female mice of a range of weights and ages were given injections of 2.5 mg cortisone acetate/day for 4 successive days beginning 11 1/3 days postconception. The frequency of offspring born with median cleft palate decreased with increasing maternal weight, advancing maternal age and increased litter sizes. Analysis of the data by multiple regression has shown that the cleft palate frequency depends on maternal weight, and that maternal age and litter size seem to play a role only because they are so highly correlated with maternal weight. In mice of constant parity, therefore, heavier animals are more resistant to the cleft palate-inducing properties of cortisone than lighter animals are. The possible role of maternal fat metabolism is discussed.

Pregnancy scanning can be used as a source of data for genetic evaluation of reproductive traits of ewes

2016 ◽  
Vol 56 (4) ◽  
pp. 679 ◽  
Author(s):  
Kim L. Bunter ◽  
Andrew A. Swan ◽  
Ian W. Purvis ◽  
Daniel Brown
Keyword(s):  
Litter Size ◽  
Genetic Parameters ◽  
Genetic Correlations ◽  
Reproductive Traits ◽  
Genetic Evaluation ◽  
Fine Tuning ◽  
Data Sources ◽  
Inconsistency Rate ◽  
Scan Data ◽  
Time Frames

Reproductive traits generated from mothering up lambs to ewes (n = 59 603 records) were compared with data resulting from pregnancy scanning (n = 46 663 records), to examine the consistency between the two data sources for deriving specific reproductive traits and to estimate genetic parameters. The reproductive traits considered were fertility (FERT: 0/1) of ewes joined, total litter size (LSIZE: lambs born), the number of lambs surviving at weaning (LSIZEW: lambs weaned) and the percentage of lambs surviving (LSURV = LSIZEW/LSIZE) for ewes that lambed, along with the composite traits number of lambs born (NLB) and number weaned (NLW) for ewes joined. Corresponding trait values were derived from pregnancy scan data (FERT_S, LSIZE_S and NLB_S) for comparison, and were classified as inconsistent if the trait values did not match from scanning and lambing records. Data were obtained from four flocks, representing different time frames, locations, management and breeds or bloodlines. Each flock recorded scan data separately from lambing outcomes. Genetic parameters were estimated separately within each flock. Average levels of inconsistency between scan- and lambing-data values varied between 4.6% and 14.8% across flocks, tending to be highest (9.1–18.5%) for litter size of ewes scanned with multiple fetuses, and lowest (0.29–7.3%) for assignment of fertility. Inconsistencies did not have a significant impact on estimates of trait heritabilities, suggesting recording errors were independent of genetic merit. In three flocks, the genetic correlations (ra) between comparable traits derived from the different data sources were not different from unity (ra ≥ 0.99) even when phenotypic correlations (rp) were lower (rp ≥ 0.84). In the flock with the highest inconsistency rate between data sources, the range in ra varied between 0.60 (fertility) and 1.0 (litter size). Therefore, pregnancy scan data can be directly substituted for reproductive traits traditionally based on lambing data, but attention should be paid to ensuring accuracy of the data sources used. Scan data also provide no information on lamb-survival outcomes after birth, so does not constitute complete data on reproductive outcomes. Genetic evaluation systems might also benefit from fine tuning for scale-induced effects (due to litter size) on parameters to improve the accuracy of across flock prediction of breeding values for reproductive traits.

scholarly journals Genetic factors of functional traits

2021 ◽  
Vol 29 (4) ◽  
pp. 207-220
Author(s):  
Mª Luz García ◽  
Melanie Gunia ◽  
Mª José Argente
Keyword(s):  
Birth Weight ◽  
Litter Size ◽  
Functional Traits ◽  
Genetic Correlations ◽  
Antibiotic Use ◽  
Production Traits ◽  
Immunity Genes ◽  
First Results ◽  
Size Variability

Selection of functional traits is a challenge for researchers, but an increasingly necessary objective due to the growing concern regarding animal welfare and overcoming the problems of reducing antibiotic use in rabbit production without undermining the animals’ productivity. The aim of this review is to discuss the genetic control of resistance to diseases, longevity and variability of birth weight within a litter, or litter size variability at birth within doe, describing the selection programmes and the first results from a multi-omics analysis of resistance/susceptibility to diseases. The heritability is around 0.13 for longevity, 0.01 for uniformity in birth weight, 0.09 for litter size variability and around 0.11 for disease resistance. Genetic correlations between functional traits and production traits are mostly no different from zero, or are moderately favourable in some cases. Six selection programmes developed in three countries are reviewed. Line foundation with high pressure for selection or divergent selection experiments are different methodologies used, and favourable responses to selection have been achieved. Genomics studies have revealed associations in regions related to immune system functionality and stress in lines selected for litter size variability. Knowledge of the role of gut microbiota in the rabbit’s immune response is very limited. A multi-omics approach can help determine the microbial mechanisms in regulation immunity genes of the host.

Methyl mercury in the dutch rhine delta

1994 ◽  
Vol 30 (10) ◽  
pp. 213-219 ◽  
Author(s):  
Hendrik Pieters ◽  
Victor Geuke
Keyword(s):  
Suspended Matter ◽  
Methyl Mercury ◽  
Mercury Contamination ◽  
Benthic Organisms ◽  
Considerable Decrease ◽  
Continuous Sedimentation ◽  
Highly Correlated ◽  
High Level ◽  
Almost All

Samples of yellow eel from various locations in the Dutch Rhine area have been analyzed for trend monitoring of mercury since 1977. In the western Rhine delta mercury levels in eels have hardly changed since the seventies, whereas in the eastern part of the Dutch Rhine area a considerable decrease of mercury concentrations in eel has occurred. Because of continuous sedimentation of contaminated suspended matter transported from upstream regions, accumulation rates and concentrations of mercury in eel in the western Rhine delta remained at a relatively high level. Analyses of methyl mercury in biota have been performed to elucidate the role of methyl mercury in the mercury contamination of the Dutch Rhine ecosystem. Low percentages of methyl mercury were observed in zooplankton (3 to 35%). In benthic organisms (mussels) percentages of methyl mercury ranged from 30 to 57%, while in fish species and liver of aquatic top predator birds almost all the mercury was present in the form of methyl mercury (> 80%). During the period 1970-1990 mercury concentrations of suspended matter in the eastern Rhine delta have drastically decreased. These concentrations seemed to be highly correlated with mercury concentrations of eel (R = 0.84). The consequences of this relation are discussed.

scholarly journals PPM1G promotes the progression of hepatocellular carcinoma via phosphorylation regulation of alternative splicing protein SRSF3

2021 ◽  
Vol 12 (8) ◽  
Author(s):  
Dawei Chen ◽  
Zhenguo Zhao ◽  
Lu Chen ◽  
Qinghua Li ◽  
Jixue Zou ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Alternative Splicing ◽  
Protein Function ◽  
Vital Role ◽  
Normal Tissues ◽  
Mechanistic Analysis ◽  
Highly Correlated ◽  
Splicing Patterns

AbstractEmerging evidence has demonstrated that alternative splicing has a vital role in regulating protein function, but how alternative splicing factors can be regulated remains unclear. We showed that the PPM1G, a protein phosphatase, regulated the phosphorylation of SRSF3 in hepatocellular carcinoma (HCC) and contributed to the proliferation, invasion, and metastasis of HCC. PPM1G was highly expressed in HCC tissues compared to adjacent normal tissues, and higher levels of PPM1G were observed in adverse staged HCCs. The higher levels of PPM1G were highly correlated with poor prognosis, which was further validated in the TCGA cohort. The knockdown of PPM1G inhibited the cell growth and invasion of HCC cell lines. Further studies showed that the knockdown of PPM1G inhibited tumor growth in vivo. The mechanistic analysis showed that the PPM1G interacted with proteins related to alternative splicing, including SRSF3. Overexpression of PPM1G promoted the dephosphorylation of SRSF3 and changed the alternative splicing patterns of genes related to the cell cycle, the transcriptional regulation in HCC cells. In addition, we also demonstrated that the promoter of PPM1G was activated by multiple transcription factors and co-activators, including MYC/MAX and EP300, MED1, and ELF1. Our study highlighted the essential role of PPM1G in HCC and shed new light on unveiling the regulation of alternative splicing in malignant transformation.

Characteristics of educators’ talk about decontextualised events

2020 ◽  
Vol 45 (4) ◽  
pp. 362-376
Author(s):  
Rebecca Andrews ◽  
Penny Van Bergen
Keyword(s):  
Communication Skills ◽  
Future Event ◽  
Time Points ◽  
Long Day ◽  
Future Events ◽  
Day Care Centres ◽  
Highly Correlated ◽  
Children’S Thinking ◽  
Sydney Australia

This study investigated the characteristics of educators’ talk about decontextualised events with young children in seven early childhood long day care centres in Sydney, Australia. Educators were partnered with up to six children aged between 27 and 60 months. Across two time points, 85 educator–child dyads discussed past and future events. Educators’ use of questions, contextual statements, evaluations and prompts and children’s use of questions, open-ended responses, yes-no responses and spontaneous information statements were examined. Educators’ evaluative statements were highly correlated and educators’ questions were moderately correlated with children’s open-ended responses in past event conversations. Educators’ evaluative statements were highly correlated with children’s open-ended responses in future event conversations and were the only significant predictor for children’s talk. Given the important role of educators in scaffolding children’s thinking and communication skills, the recommended strategies for educators’ talk in decontextualised conversations include: sharing the conversational load, making frequent contextual statements and following the child’s lead/interests.

scholarly journals Comparison of two live-animal ultrasound systems for genetic evaluation of carcass traits in Angus cattle

2021 ◽  
Author(s):  
C J Duff ◽  
J H J van der Werf ◽  
P F Parnell ◽  
S A Clark
Keyword(s):  
Carcass Traits ◽  
Genetic Correlations ◽  
Subcutaneous Fat ◽  
Genetic Evaluation ◽  
Ultrasound Scan ◽  
Ultrasound Scanning ◽  
Eye Muscle ◽  
Angus Cattle ◽  
Breeding Objective ◽  
Two Systems

Abstract The improvement of carcass traits is an important breeding objective in beef cattle breeding programs. The most common way of selecting for improvement in carcass traits is via indirect selection using ultrasound scanning of selection candidates which are submitted to genetic evaluation programs. Two systems used to analyse ultrasound images to predict carcass traits are the Pie Medical Esaote Aquila (PIE) and Central Ultrasound Processing (CUP). This study compared the ability of the two systems to predict carcass traits for genetic evaluation in Australian Angus cattle. Genetic and phenotypic parameters were estimated using data from 1648 Angus steers which were ultrasound scanned twice with both systems, first at feedlot entry and then following 100 days in the feedlot. The traits interpreted from ultrasound scanning included eye muscle area (EMA), rib fat (RIB) rump fat (RUMP) and intramuscular fat (IMF). Abattoir carcass data were collected on all steers following the full feedlot feeding period of 285 days. For all ultrasound scan traits, CUP resulted in higher phenotypic and genetic variances compared to the PIE. For IMF, CUP had higher heritability at feedlot intake (0.51 for CUP compared to 0.37 for PIE) and after 100 days feeding (0.54 for CUP compared to 0.45 PIE). CUP predicted IMF also tended to have stronger correlations with the breeding objective traits of carcass IMF marbling traits, both genetically (ranging from 0.59 to 0.75 for CUP compared to 0.45 to 0.63 for PIE) and phenotypically (ranging from 0.27 to 0.43 for CUP compared to 0.19 to 0.28 for PIE). Ultrasound scan EMA were the only group of traits in which the heritabilities were higher for PIE (0.52 for PIE compared to 0.40 for CUP at feedlot intake and 0.46 for PIE compared to 0.43 for CUP at 100 days of feeding), however with similar relationships to the breeding objective carcass EMA observed. For subcutaneous fat traits of ultrasound RIB and RUMP, the heritabilites and genetic correlations to the related carcass traits were similar, with the exception being the higher heritability observed for CUP predicted RUMP at feedlot intake at 0.52 compared to 0.38 for PIE. The results from this study indicates that the CUP system, compared to PIE, provides an advantage for genetic evaluation of carcass traits in Angus cattle, particularly for the IMF and associated marbling traits.

NEURAL FACTORS IN THE MAINTENANCE OF LACTATION IN THE RAT

1967 ◽  
Vol 38 (1) ◽  
pp. 51-59 ◽  
Author(s):  
J. A. EDWARDSON ◽  
J. T. EAYRS
Keyword(s):  
Litter Size ◽  
Milk Yield ◽  
Quantitative Relationship ◽  
Mammary Tissue ◽  
Single Pair ◽  
Endocrine Response ◽  
Peripheral Innervation ◽  
Lactational Performance ◽  
Neural Factors

SUMMARY The role of the peripheral innervation of mammary tissue in the maintenance of lactation has been investigated by the procedure of selective thelectomy combined with denervation of the posterior thoracic nipples. When suckling is restricted to a single pair of nipples bilateral transection of the three adjacent nerves supplying a nipple arrests lactation completely; partial denervation is associated with a reduced level of lactational performance which is directly related to the concentration of the residual innervation. Increase in litter size is associated with an overall increase in milk-yield up to a limit beyond which the addition of further young to the litter is without effect. It is inferred that there is a quantitative relationship between the neural stimulus of suckling and the endocrine response of the hypothalamopituitary system.

Pre-service music teachers' satisfaction: person–environment fit approach

2012 ◽  
Vol 29 (3) ◽  
pp. 371-385 ◽  
Author(s):  
Serkan Perkmen ◽  
Beste Cevik ◽  
Mahir Alkan
Keyword(s):  
Music Education ◽  
Music Teachers ◽  
Music Teacher ◽  
Theoretical Frameworks ◽  
Vocational Satisfaction ◽  
Highly Correlated ◽  
Service Music ◽  
And Control ◽  
Future Work

Guided by three theoretical frameworks in vocational psychology, (i) theory of work adjustment, (ii) two factor theory, and (iii) value discrepancy theory, the purpose of this study was to investigate Turkish pre-service music teachers' values and the role of fit between person and environment in understanding vocational satisfaction. Participants were 85 students enrolled in the department of music education in a Turkish university. The Minnesota Importance Questionnaire (MIQ) was used to examine the participants’ values in six dimensions: achievement, comfort, status, altruism, safety and autonomy. Results revealed that the pre-service teachers value achievement most followed by autonomy, which suggests that they would like to have a sense of accomplishment and control in their future job. The degree to which their values fit their predictions about future work environment was found to be highly correlated with vocational satisfaction. These results provided evidence that the vocational theories used in the current study offers a helpful and different perspective to understand the pre-service teachers' satisfaction with becoming a music teacher in the future. We believe that researchers in the field of music education may use these theories and MIQ to examine the role of values in pre-service and in-service music teachers' job satisfaction.

scholarly journals Heterologous desensitization of the cyclic AMP-independent glycogenolytic response in rat liver cells

1981 ◽  
Vol 200 (3) ◽  
pp. 509-514 ◽  
Author(s):  
B Bréant ◽  
S Keppens ◽  
H De Wulf
Keyword(s):  
Cyclic Amp ◽  
Glycogen Phosphorylase ◽  
Liver Glycogen ◽  
Receptor Interaction ◽  
Alpha Adrenergic Receptors ◽  
Rat Liver Cells ◽  
Heterologous Desensitization ◽  
Highly Correlated ◽  
Alpha Agonist

Vasopressin and alpha-adrenergic agonists are known to be potent cyclic AMP-independent Ca2+-dependent activators of liver glycogen phosphorylase. When hepatocytes are pre-incubated with increasing concentrations of vasopressin or of the alpha-agonist phenylephrine, they become progressively unresponsive to a second addition of the respective agonist. The relative abilities of six vasopressin analogues and of five alpha-agonists to activate glycogen phosphorylase and to cause subsequent desensitization are highly correlated, indicating that the same vasopressin and alpha-adrenergic receptors are involved in both responses. About 5-times-higher peptide concentrations are needed to desensitize the cells than to activate their glycogen phosphorylase, whereas the concentrations of alpha-agonists required for the desensitization are only twice those needed for the activation of phosphorylase. The desensitization is not mediated by a perturbation in the agonist-receptor interaction. It is clearly heterologous, i.e. it is not agonist-specific, and must therefore involve a mechanism common to both series of agonists. The evidence for a role of Ca2+ movements or phosphatidylinositol turnover is briefly discussed.

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