Estimates of genetic and phenotypic parameters for production, haematological and gastrointestinal nematode-associated traits in Australian cashmere goats

2011 ◽  
Vol 51 (2) ◽  
pp. 123 ◽  
Author(s):  
M. E. Olayemi ◽  
S. Bolormaa ◽  
J. H. J. van der Werf ◽  
N. Baillie ◽  
L. F. Le Jambre ◽  
...  

The present study was designed to estimate genetic parameters of 17 production, parasite-associated and haematological traits in Australian cashmere goats. It comprised 796 records of female progeny of 532 dams sired by 29 bucks over a 4-year period. Measurement of haematological and parasite-associated traits was carried out on female kids during low-level natural gastrointestinal nematode challenge at 3 and 5 months of age and at 28 and/or 35 days after artificial challenge with 10 000 infective larvae of Trichostrongylus colubriformis administered 1 week after the 5-month measurement. Production traits were measured up to 18 months of age. Year of birth significantly affected all traits apart from cashmere diameter (CSD). Twin kids had significantly lower liveweight (up to 10 months), packed cell volume and mean corpuscular volume (at 3 and 5 months) but higher specific IgG levels and mean corpuscular haemoglobin content at 3 months. Paddock of birth and early rearing and its interaction with year of birth had significant effects on worm egg count (WEC) during natural challenge, on IgG at both natural and post-artificial challenge measurements and on liveweight at early ages. The level of gastrointestinal nematode challenge in the nine different paddocks clearly influenced both WEC and IgG during natural and subsequent artificial challenge. Maternal permanent environmental effects were important only for liveweights at 3 month of age and for IgG at 5 months of age. For other traits, a simple animal model without maternal permanent environmental effects gave the best fit. Estimates of heritability (h2) of WEC and IgG were low (0.06–0.22) with the highest h2 estimates occurring after 5 months of natural infection or 35 days after artificial challenge. The majority of fleece traits were moderately to highly heritable, ranging from 0.38 to 0.78. The h2 estimates for mean fibre curvature are novel for cashmere goats and were moderate, varying from 0.32 to 0.48. Heritability estimates for erythrocyte traits were uniformly high (0.49–0.98) while those for leukocyte traits varied from low to moderate (0.09–0.43). Strong genetic and phenotypic correlations existed between major production traits. Due to the comparatively small dataset, the standard errors of genetic correlations were relatively high. CSD was positively correlated with cashmere weight and yield, an unfavourable direction. CSD was negatively correlated with fibre curvature, indicating that animals producing finer fibres produce cashmere with a higher crimp count. No phenotypic relationships were observed between WEC and fleece traits. Liveweight was weakly but negatively correlated with WEC and circulating neutrophils, while it was positively associated with eosinophils, lymphocytes and packed cell volume. This study has shown that selection for increased resistance to gastrointestinal nematode infection cashmere goats is possible but progress will be slow. WEC should remain the phenotypic marker of choice and the additional cost of alternative measures of resistance is not justified. Many of the parasite-associated traits appear to under independent genetic control.

2021 ◽  
Vol 99 (Supplement_3) ◽  
pp. 8-9
Author(s):  
Guoyu Hu ◽  
Duy Ngoc Do ◽  
Karim Karimi ◽  
Younes Miar

Abstract Aleutian disease (AD) is an untreatable immune complex disease in mink and brings tremendous economic losses to the mink industry globally. The ineffectiveness of culling, immunoprophylaxis, and medical treatment in controlling AD have urged mink farmers to select AD-resilient mink based on the AD tests. However, the genetic analysis of these tests and their correlations with AD-resilient traits have not been investigated. In this study, data on 5,824 mink were used to estimate the genetic and phenotypic parameters of four AD tests, including two systems of enzyme-linked immunosorbent assay (ELISA), counterimmunoelectrophoresis (CIEP), and iodine agglutination test (IAT), and their genetic and phenotypic correlations with pelt quality, reproductive performance, packed-cell volume (PCV), and harvest length (HL). Significance (P < 0.05) of fixed effects (sex, year, color type, the number of mating, and dam age), covariates (age at blood sampling and age at harvest), and random effects (additive genetic, permanent environmental, and maternal effects) were determined using univariate models. The genetic and phenotypic parameters for all traits were estimated under bivariate models using ASReml 4.1. Estimated heritabilities (±SE) were 0.39±0.05, 0.61±0.07, 0.11±0.07, and 0.26±0.05 for antigen-based ELISA (ELISA-G), virus capsid protein-based ELISA, CIEP, and IAT, respectively. The ELISA-G showed moderate repeatability (0.58±0.04) and significant (P < 0.05) negative genetic correlations (±SE) with reproductive performance traits (from -0.41±0.16 to -0.49±0.12), PCV (-0.53±0.09), and HL (-0.45±0.16). These results indicated that the selection of mink with a lower ELISA-G score could not only decrease the anti-AMDV antibody level and the extent of anemia but also improve the female reproductive performance and the harvest length of mink without causing adverse influences on the pelt quality. Hence, ELISA-G could be applied as an indicator for genetic selection of AD-resilient mink and help mink farmers reduce the adverse effects of AD.


2010 ◽  
Vol 50 (1) ◽  
pp. 25 ◽  
Author(s):  
S. Bolormaa ◽  
M. Olayemi ◽  
J. H. J. van der Werf ◽  
N. Baillie ◽  
F. Le Jambre ◽  
...  

Genetic parameters for liveweight (LWT), greasy fleece weight (GFW), mean fibre diameter (MFD), standard deviation of MFD (MFD-s.d.), mean fibre curvature (CURVE) percentage of medullated (%MED) and kemp (%KEMP) fibres, faecal worm egg count (WEC), packed cell volume (PCV), mean corpuscular volume (MCV) mean corpuscular haemoglobin content (MCHC), circulating anti-nematode IgG (IgG) and counts of circulating eosinophils (EOS), lymphocytes (LYM), neutrophils (NEU), basophils (BASO) and monocytes (MONO) up to 18 months of age were estimated in Australian Angora goats (608 animals, 14 sires 3 years of birth). Measurements were made during a period of natural parasite challenge up to 5 months of age, or following artificial challenge with 10 000 infective larvae of Trichostrongylus colubriformis at 5.25 months of age. Year of birth had a significant impact on production and parasite-associated traits at all ages studied. Sex had a marked effect on production and erythrocyte traits. Birth type had no effect on any traits in animals older than 6 months. Maternal effects were not significant except for LWT at 3, 5 and 6 months and for IgG at 3 months. Most production traits were highly (LWT, GFW, MFD, %MED) or moderately (CURVE, MFD-s.d.) heritable (range 0.17–0.59) with only %KEMP having a low heritability (0.02–0.14). The heritability estimates (±s.e.) for CURVE are novel for goats and ranged from 0.18 ± 0.09 at first shearing to 0.44 ± 0.14 at third shearing. Heritability estimates were low for WEC (0.02–0.16) and for specific IgG during natural infection (0.14–0.15) but higher for IgG following artificial challenge with T. colubriformis (0.42 ± 0.13). Of the haematological variables NEU and all red cell traits were highly heritable (0.45–0.71), LYM and MONO were moderately to highly heritable (0.31–0.55), and EOS was weakly to moderately heritable (0.06–0.28). Strong phenotypic correlations existed between production traits. MFD was positively correlated with GFW and negatively correlated with CURVE, indicating that finer fibres have a higher crimp or wave count. WEC had consistent negative phenotypic correlations with PCV, LYM and EOS, and positive correlations with NEU. Correlations with IgG were positive up to 5 months and negative thereafter. Phenotypic correlations between WEC and LWT as well as with GFW and MFD were negative. Heritability estimates for production traits were generally consistent with other studies. Haematological and fibre curvature findings are completely novel for Angora goats. Estimates of heritability for WEC fell in mid range of published findings for other goat breeds, and these results suggest that there is some scope for breeding for worm resistance in Angoras but the response is likely to be slow.


Author(s):  
Jennifer Mayara GASPARINA ◽  
Lidiane FONSECA ◽  
Maria Marta LODDI ◽  
Adriana de Souza MARTINS ◽  
Raquel Abdallah da ROCHA

ABSTRACT This study aimed to evaluate the resistance of Texel (Tx) and Ile de France (IF) sheep to gastrointestinal nematode infections in the periparturient period and after weaning, and the performance of their lambs. Fecal samples were collected from 19 IF and 17 Texel ewes to determine fecal egg counts (FEC) and larval cultures were prepared to determine the prevalence of nematodes. The ewes were weighed to determine body weight (BW) and blood samples were taken to determine the packed cell volume (PCV) and plasm protein values (PPV). The ewes were classified into two groups by FEC (heavy and moderate infection). The IF presented higher FECs than Tx 28 and 14 days before parturition; 14, 28, and 56 days after parturition; and 28 days after weaning (P<0.05). In the weaning and dry periods, the IF presented higher PCVs than Tx (P<0.05). The PPV did not differ between the groups (P>0.05). The IF presented a higher BW than Tx 14, 28, and 42 days after parturition, and in the weaning and dry periods (P<0.05). The ewes of both breeds classified as moderately infected had the highest BW at weaning (P<0.05). IF ewes with a moderate infection produced weaning lambs that were heavier than those of Tx with the same level of infection (P<0.05). Overall, Tx ewes presented a better ability to withstand infections during the periparturient period and after weaning. Although the IF ewes presented the highest FEC and more intense periparturient rise, they managed to maintain their level of production.


2001 ◽  
Vol 21 (4) ◽  
pp. 146-150 ◽  
Author(s):  
Valeska S.P. Melo ◽  
Lygia M.F. Passos ◽  
Elias J. Facury-Filho ◽  
Helton M. Saturnino ◽  
Múcio F.B. Ribeiro

The dynamic of natural infections by Anaplasma marginale in calves was evaluated during a period of one year on two farms located in the Metalúrgica Region, State of Minas Gerais, Brazil. Blood samples were collected weekly for rickettsemia and packed cell volume (PCV) determination. The animals born from March to July suffered the infection in October and November, independently of their age, whilst calves born from September to December acquired the infection during the first days of life. These animals presented patent rickettsemia from 30 days of life. During the patent period PCV decreased after one week of infection, ranging from 20 to 23%. It was concluded, that in the region studied, the transmission of A. marginale is influenced by climatic conditions, and that calves born during the dry season are more likely to acquire the infection when they are exposed to high transmission levels during the subsequent raining season.


Author(s):  
Guoyu Hu ◽  
Duy Ngoc Do ◽  
Karim Karimi ◽  
Younes Miar

Abstract Aleutian disease (AD), caused by the Aleutian mink disease virus (AMDV), is a major health concern that results in global economic losses to the mink industry. The unsatisfactory outcome of the culling strategy, immunoprophylaxis, and medical treatment in controlling AD have urged mink farmers to select AD resilient mink based on several detection tests, including enzyme-linked immunosorbent assay (ELISA), counterimmunoelectrophoresis (CIEP), and iodine agglutination test (IAT). However, the genetic analysis of these AD tests and their correlations with pelt quality, reproductive performance, packed-cell volume (PCV), and harvest length (HL) have not been investigated. In this study, data on 5,824 mink were used to estimate the genetic and phenotypic parameters of four AD tests, including two systems of ELISA, CIEP, and IAT, and their genetic and phenotypic correlations with two pelt quality, five female reproductive performance, PCV, and HL traits. Significances (P&lt;0.05) of fixed effects (sex, year, dam age, and color type), covariates (age at harvest and blood sampling ), and random effects (additive genetic, permanent environmental, and maternal effects) were determined under univariate models using ASReml 4.1 software. The genetic and phenotypic parameters for all traits were estimated under bivariate models using ASReml 4.1 software. Estimated heritabilities (±SE) were 0.39±0.06, 0.61±0.07, 0.11±0.07, and 0.26±0.05 for AMDV antigen-based ELISA (ELISA-G), AMDV capsid protein-based ELISA, CIEP, and IAT, respectively. The ELISA-G also showed a moderate repeatability (0.58±0.04) and had significant negative genetic correlations (±SE) with reproductive performance traits (from -0.41±0.16 to -0.49±0.12), PCV (-0.53±0.09), and HL (-0.45±0.16). These results indicated that ELISA-G had the potential to be applied as an indicator trait for genetic selection of AD resilient mink in AD endemic ranches, and therefore help mink farmers to reduce the adverse effects caused by AD.


Antibiotics ◽  
2021 ◽  
Vol 10 (7) ◽  
pp. 829
Author(s):  
Wim Gorssen ◽  
Dominiek Maes ◽  
Roel Meyermans ◽  
Jürgen Depuydt ◽  
Steven Janssens ◽  
...  

The use of antimicrobials in animal production is under public debate, mainly due to the risk of transfer of resistance to pathogenic bacteria in humans. Therefore, measures have been taken during the last few decades to reduce antibiotic usage in animals, for instance, by national monitoring programmes and by improving animal health management. Although some initiatives exist in molecular genetic selection, quantitative genetic selection of animals towards decreased antibiotic usage is an underexplored area to reduce antibiotic usage. However, this strategy could yield cumulative effects. In this study, we derived new phenotypes from on-farm parenteral antibiotic records from commercially grown crossbred finishing pigs used in the progeny test of Piétrain terminal sires to investigate the heritability of antibiotics usage. Parenteral antibiotic records, production parameters and pedigree records of 2238 full-sib pens from two experimental farms in Belgium between 2014 and 2020 were analysed. Heritability estimates were moderate (18–44%) for phenotypes derived from all antibiotic treatments, and low (1–15%) for phenotypes derived from treatments against respiratory diseases only. Moreover, genetic correlations between these new phenotypes and mortality were low to moderate (0.08–0.60) and no strong adverse genetic correlations with production traits were found. The high heritabilities and favourable genetic correlations suggest these new phenotypes, derived from on-farm antibiotics records, to be promising for inclusion in future pig breeding programs to breed for a decrease in antibiotics usage.


2021 ◽  
Vol 99 (Supplement_1) ◽  
pp. 20-20
Author(s):  
Robert A Cushman ◽  
Alexandria Snider ◽  
Matthew S Crouse

Abstract While sequence variation can be informative to associate regions of the genome with specific traits and improve genetic selection, the epigenome may provide a more powerful tool to manage cattle. Identifying practices that are producer friendly and effectively control epigenetic function within animals is crucial to translating developmental programming to a production setting. Initial studies of developmental programming investigated how environmental or nutritional stresses during fetal and peri-natal development impacted performance of animals later in life. These studies demonstrated changes in methylation, alterations in transcript abundance, and negative impacts on physiology, but they also suggested that we may be able to beneficially impact the epigenome and developmentally program animals to excel in their niche in the production system. Maternal nutritional status during the third trimester influenced date of conception of female progeny in several studies but failed to do so in other studies. Transcriptomic analyses provided evidence that nutritional treatments alter mRNA abundance in brain, liver, muscle, and ovary, but does not conclusively demonstrate that this is due to functional changes in the epigenome. If developmental programming is to be applied in production systems, responses must be consistent and beneficial. Reducing nutrient intake in heifers during peri-pubertal development increased number of primordial follicles in the ovaries and reproductive longevity. While nutritional programming of the ovarian reserve in peri-pubertal heifers appears to occur consistently across locations and studies, it does not ensure that subsequent environmental stressors will not induce changes in the ovarian reserve that will negate beneficial effects. These studies demonstrate that it is possible to developmentally program the epigenome in cattle in ways that will improve production traits; however, there remains a need for studies to improve the consistency of response and to determine best practices that fit into production systems. USDA is an equal opportunity provider and employer.


1989 ◽  
Vol 40 (2) ◽  
pp. 433 ◽  
Author(s):  
SI Mortimer ◽  
KD Atkins

Wool production traits were measured on Merino hogget ewes in an unselected multiple-bloodline flock over a 7-year period at Trangie Agricultural Research Centre, N.S.W. The traits measured were greasy fleece weight (GFW), skirted fleece weight (SKFW), yield (Y), clean fleece weight (CFW), fibre diameter (FD), body weight (BWT) and staple length (SL). These measurements were used to examine genetic differences between and within flocks of Merino sheep, and to estimate heritability of and genetic and phenotypic correlations among these traits. Significant strain, flock within strain and flock effects were present for all traits. Interactions between these effects and year were non-significant. Within-flock genetic variance was always larger than between-flock within strain genetic variance for each trait. The influence of environmental effects on these traits was also examined. The environmental effects of birth-rearing type, age at observation and age of dam together accounted for about 7-10% of the total within-flock variation in fleece weights and body weight.After adjusting for significant environmental effects, paternal half-sib heritability estimates were 0.29 �. 0.06 for GFW, 0.22 � 0.05 for SKFW, 0.35 � 0.05 for Y, 0.30 �0.06 for CFW, 0.48 �0.07 for FD, 0.34 �. 0.06 for BWT and 0.44 �0.07 for SL. Estimates for genetic and phenotypic correlations were in agreement with published estimates except for the genetic correlation between CFW and FD (0.40 �. 0.11), and the genetic correlations involving BWT, which were essentially zero. The implications of the results of this study for the genetic improvement of Merino sheep for wool production are discussed.


2018 ◽  
Vol 58 (10) ◽  
pp. 1966
Author(s):  
Purna Kandel ◽  
Sylvie Vanderick ◽  
Marie-Laure Vanrobays ◽  
Hélène Soyeurt ◽  
Nicolas Gengler

Methane (CH4) emission is an important environmental trait in dairy cows. Breeding aiming to mitigate CH4 emissions require the estimation of genetic correlations with other economically important traits and the prediction of their selection response. In this study, test-day CH4 emissions were predicted from milk mid-infrared spectra of Holstein cows. Predicted CH4 emissions (PME) and log-transformed CH4 intensity (LMI) computed as the natural logarithm of PME divided by milk yield (MY). Genetic correlations of PME and LMI with traits used currently were approximated from correlations between estimated breeding values of sires. Values were for PME with MY 0.06, fat yield (FY) 0.09, protein yield (PY) 0.13, fertility 0.17; body condition score (BCS) –0.02; udder health (UDH) 0.22; and longevity 0.22. As expected by its definition, values were negative for LMI with production traits (MY –0.61; FY –0.15 and PY –0.40) and positive with fertility (0.36); BCS (0.20); UDH (0.08) and longevity (0.06). The genetic correlations of 33 type traits with PME ranged from –0.12 to 0.25 and for LMI ranged from –0.22 to 0.18. Without selecting PME and LMI (status quo) the relative genetic change through correlated responses of other traits were in PME by 2% and in LMI by –15%, but only due to the correlated response to MY. Results showed for PME that direct selection of this environmental trait would reduce milk carbon foot print but would also affect negatively fertility. Therefore, more profound changes in current indexes will be required than simply adding environmental traits as these traits also affect the expected progress of other traits.


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