Efficiency of nucleus breeding schemes in dual-purpose cattle of Tanzania

1990 ◽  
Vol 50 (2) ◽  
pp. 245-251 ◽  
Author(s):  
J. S. Kasonta ◽  
G. Nitter
Keyword(s):  
Artificial Insemination ◽  
Genetic Gain ◽  
Cattle Breed ◽  
Progeny Testing ◽  
Environment Interaction ◽  
Dual Purpose ◽  
Model Calculations ◽  
Dual Purpose Cattle ◽  
Total Profit ◽  
Breeding Schemes

ABSTRACTFor the Mpwapwa cattle breed in Tanzania, the efficiency of various breeding schemes including an open nucleus was investigated by model calculations. Artificial insemination and intensive recording of production are assumed to be applied in a nucleus which is the main breeding unit. As a pre-nucleus, associated herds with less intense data recording serve as the basis to screen superior cows for nucleus replacements, provide the capacity for progeny testing, and operate as bull multipliers for commercial herds.The criteria of efficiency were genetic gain and profit from selection for a dual purpose breeding objective (milk and beef) in a total population of 10 000 cows. Introducing a two breeding tier scheme through separating all recorded cows into a nucleus and pre-nucleus leads to an increase of the genetic gain rather than the profit. Further improvement is obtained by introduction of artificial insemination in pre-nucleus herds. The nucleus size should not exceed about 5% of the cow population and an optimum size of the pre-nucleus is about 15%. Opening the nucleus to replacement cows coming from the pre-nucleus affects the aggregate genetic gain very little although it can be recommended if milk yield is to be mainly improved or if the total profit is taken into account. Furthermore, the nucleus should be opened if there is little difference between the heritabilities in the nucleus and pre-nucleus and also in order to avoid detrimental effects of inbreeding and genotype × environment interaction.

scholarly journals Ecological total merit index for an Austrian dual purpose cattle breed

2001 ◽  
Vol 44 (1) ◽  
pp. 5-14 ◽  
Author(s):  
R. Baumung ◽  
J. Sölkner ◽  
E. Gierzinger ◽  
A. Willam
Keyword(s):  
Milk Production ◽  
Functional Traits ◽  
Cattle Breed ◽  
Production Traits ◽  
Dual Purpose ◽  
Economic Values ◽  
Model Calculations ◽  
Ecological Index ◽  
Dual Purpose Cattle ◽  
The Impact

Abstract. Organic farming plays a considerable role in Austrian agriculture. Therefore it seems to be worthwhile to make suggestions about a more ecological breeding goal for cattle breeds. Because of the fact that Simmental is the most frequent dual purpose cattle breed in Austria, this breed is chosen to show the impact of selection under an ecological total merit index. With model calculations the effect on selection response in milk production beef production and functional traits under selection with the current economic total merit index and more ecological index variants, e.g. with higher economic values for fitness and functional traits, is shown. As a basis for future decisions the efficiency of more or less ecological indices is compared. The results indicate that an increase of the current economic values of functional traits of about 50 percent does not present a great risk, expected selection responses for milk production traits are still high.

Environmental and genetic variation for grain yield and barley malting quality attributes

1999 ◽  
Vol 50 (8) ◽  
pp. 1425 ◽  
Author(s):  
M. Q. Lu ◽  
L. O'Brien ◽  
I. M. Stuart
Keyword(s):  
Grain Yield ◽  
Protein Content ◽  
Genetic Gain ◽  
Quality Attributes ◽  
Malting Quality ◽  
Malt Extract ◽  
Progeny Testing ◽  
Environment Interaction ◽  
Wide Range ◽  
Selection For

Genotype, environment, and genotype × environment interaction effects for malting quality attributes and grain yield were investigated using breeding lines from the F2, F3, and F4 generations and the parental varieties of 4 barley crosses. There were significant differences between the parental varieties for all attributes studied. Both malting quality and grain yield exhibited a wide range among progenies in all generations. While performance of the parental varieties and progeny for malting quality and grain yield were greatly influenced by environment, performance in one environment was predictive of that in other environments. Only for grain protein content was there evidence of crossover G × E interaction. Heritability was generally higher for F3 to F4 than for F2 to F3 for all malting quality attributes. F3 on F2 regression per cent heritability estimates for protein content, potential malt extract and grain weight were all highly significant with values generally medium in magnitude. Genetic gain was obtained from selection in both the F2 and F3 generations. Heritability and genetic gain varied from cross to cross for diastatic power. Progress from selection for the other quality attributes attests to the potential value of NIT (near infrared transmittance) spectroscopy for predicting potential malting quality. Heritability for F2 to F3 for grain yield was not significant in any cross, indicating selection for yield on the basis of individual F2 plant yield was ineffective. Heritability for grain yield from F3 to F4 was highly significant and medium in magnitude for 3 of the 4 crosses. The results of this study indicate that good genetic gain could be expected from early generation selection for potential malting quality using NIT spectroscopy and for grain yield using F3 progeny testing.

scholarly journals Designing dairy cattle breeding schemes under genomic selection: a review of international research

2012 ◽  
Vol 52 (3) ◽  
pp. 107 ◽  
Author(s):  
J. E. Pryce ◽  
H. D. Daetwyler
Keyword(s):  
Dairy Cattle ◽  
Genomic Selection ◽  
Genetic Gain ◽  
Reproductive Technologies ◽  
Progeny Testing ◽  
Genomic Breeding ◽  
Breeding Values ◽  
Scheme Design ◽  
Dairy Cattle Breeding ◽  
Breeding Schemes

High rates of genetic gain can be achieved through (1) accurate predictions of breeding values (2) high intensities of selection and (3) shorter generation intervals. Reliabilities of ~60% are currently achievable using genomic selection in dairy cattle. This breakthrough means that selection of animals can happen at a very early age (i.e. as soon as a DNA sample is available) and has opened opportunities to radically redesign breeding schemes. Most research over the past decade has focussed on the feasibility of genomic selection, especially how to increase the accuracy of genomic breeding values. More recently, how to apply genomic technology to breeding schemes has generated a lot of interest. Some of this research remains the intellectual property of breeding companies, but there are examples in the public domain. Here we review published research into breeding scheme design using genomic selection and evaluate which designs appear to be promising (in terms of rates of genetic gain) and those that may have unfavourable side-effects (i.e. increasing the rate of inbreeding). The schemes range from fairly conservative designs where bulls are screened genomically to reduce numbers entering progeny testing, to schemes where very large numbers of bull calves are screened and used as sires as soon as they reach sexual maturity. More radical schemes that incorporate the use of reproductive technologies (in juveniles) and genomic selection in nucleus herds are also described. The models used are either deterministic and more recently tend to be stochastic, simulating populations of cattle. A key driver of the rate of genetic gain is the generation interval, which could range from being similar to that in conventional testing (~5 years), down to as little as 1.5 years. Generally, the rate of genetic gain is between 12% and 100% more than in conventional progeny testing, while the rate of inbreeding tends to be lower per generation than in progeny testing because Mendelian sampling terms can be estimated more accurately. However, short generation intervals can lead to higher rates of inbreeding per year in genomic breeding programs.

Genetic and non-genetic factors affecting productive and reproductive traits in Deoni cattle

2018 ◽  
Author(s):  
Sukanta Basak ◽  
D. N. Das ◽  
U. T. Mundhe
Keyword(s):  
Milk Yield ◽  
Genetic Factors ◽  
Cattle Breed ◽  
Reproductive Traits ◽  
Phenotypic Correlation ◽  
Dual Purpose ◽  
Factors Affecting ◽  
Lactation Length ◽  
Service Period ◽  
Dual Purpose Cattle

The present study was carried out in Deoni, the dual purpose cattle breed of Southern India, maintained at NDRI herd, SRS, Bengaluru. Mean phenotypic performances for the traits of age at first calving (AFC), first service period (FSP), first lactation milk yield (FLMY) and first lactation length (FLL) were estimated as 42.90 ± 0.49 months, 179.00 ± 6.3 days, 643.08 ± 25.16 kg and 178.24 ± 4.41 days respectively. Significant effect of parity was found on AFC and FSP. Effect of period of birth, period of calving and season of calving was found to be significant on FSP. Significant effect of period of birth, period of calving, classes of AFC and FLL were found on FLMY. The heritability of first lactation milk yield was estimated as 0.38 ± 0.29. Phenotypic correlation of FLMY with FLL (0.88 ± 0.02) was found to be highly significant (p Lass Than 0.01).

SITUATION OF INBREEDING IN A RETINTO POPULATION

1996 ◽  
Vol 17 ◽  
pp. 87-93
Author(s):  
I. Serrano ◽  
M. Mayer ◽  
A. Rodero ◽  
J. M. Jimenez
Keyword(s):  
Beef Cattle ◽  
Cattle Breed ◽  
Pedigree Information ◽  
Dual Purpose ◽  
Average Coefficient ◽  
Dual Purpose Cattle ◽  
Beef Cattle Breeds ◽  
Available Information ◽  
Close Inbreeding ◽  
Very High

SUMMARYThe degree of inbreeding was studied for a subpopulation of the beef cattle breed Retintofrom the Cadiz Province in Andalusia (Spain). The pedigree information from 492 female and 25 male breeding animals was analyzed. On the basis of the available information, only the current inbreeding, that is the inbreeding with consideration of three ancestral generations, could be calculated. While close inbreeding is purposely avoided with the bulls, it is of great importance in cows. The average coefficient of inbreeding for cows born inthe years 1982 to 1987 was o 2.35 /;o, although in the great-grandparent generation only 55% of the ancestors were known. Inbreeding was discovered in 17.7% of the cows; 5.8%of the cows had an inbreeding coefficient of 25%. The rate of inbreeding per generation is very high in comparison with other beef cattle breeds and above all in comparison with dual purpose cattle. Because of the manner in which the bulls are used, also considerablenon-current inbreeding has to be expected.

scholarly journals Time-lagged and acute impact of heat stress on production and fertility traits in the local dual-purpose cattle breed “Rotes Höhenvieh” under pasture-based conditions

2020 ◽  
Vol 4 (3) ◽  
Author(s):  
Kathrin Halli ◽  
Kerstin Brügemann ◽  
Mehdi Bohlouli ◽  
Sven König
Keyword(s):  
Heat Stress ◽  
Linear Mixed Model ◽  
Cattle Breed ◽  
Extreme Weather Events ◽  
Seasonal Effect ◽  
Dual Purpose ◽  
Link Functions ◽  
Weight Gains ◽  
Dual Purpose Cattle ◽  
Time Lagged

Abstract Climate change causes rising temperatures and extreme weather events worldwide, with possible detrimental time-lagged and acute impact on production and functional traits of cattle kept in outdoor production systems. The aim of the present study was to infer the influence of mean daily temperature humidity index (mTHI) and number of heat stress days (nHS) from different recording periods on birth weight (BWT), 200 d- and 365 d-weight gain (200 dg, 365 dg) of calves, and on the probability of stillbirth (SB), and calving interval (CINT) of their dams. Data recording included 4,362 observations for BWT, 3,136 observations for 200 dg, 2,502 observations for 365 dg, 9,293 observations for the birth status, and 2,811 observations for CINT of the local dual-purpose cattle breed “Rotes Höhenvieh” (RHV). Trait responses on mTHI and nHS were studied via generalized linear mixed model applications with identity link functions for Gaussian traits (BWT, 200 dg, 365 dg, CINT) and logit link functions for binary SB. High mTHI and high nHS before autumn births had strongest detrimental impact on BWT across all antepartum- (a.p.) periods (34.4 ± 0.79 kg maximum). Prolonged CINT was observed when cows suffered heat stress (HS) before or after spring calvings, with maximum length of 391.6 ± 3.82 d (56 d a.p.-period). High mTHI and high nHS during the 42 d- and 56 d a.p.-period implied increased probabilities for SB. We found a significant (P < 0.05) seasonal effect on SB in model 3 across all a.p.-periods, with the highest probability in autumn (maximum of 5.4 ± 0.82% in the 7 d a.p.-period). Weight gains of calves (200 dg and 365 dg) showed strongest HS response for mTHI and nHS measurements from the long-term postnatal periods (42 d- and 56 d-periods), with minimum 200 dg of 194.2 ± 4.15 kg (nHS of 31 to 42 d in the 42 d-period) or minimum 365 dg of 323.8 ± 3.82 kg (mTHI ≥ 60 in the 42 d-period). Calves born in summer, combined with high mTHI or high nHS pre- or postnatal, had lower weight gains, compared with calves born in other calving seasons or under cooler conditions. Highest BWT, weight gains, and shortest CINT mostly were detected under cool to moderate climate conditions for mTHI, and small to moderate nHS. Results indicate acute and time-lagged HS effects and address possible HS-induced epigenetic modifications of the bovine genome across generations and limited acclimatization processes to heat, especially when heat occurs during the cooler spring and autumn months.

scholarly journals Inseminación artificial a tiempo fijo en vacas con proestro prolongado de 60 y 72 horas

2018 ◽  
Vol 29 (2) ◽  
pp. 363
Author(s):  
Darwin Omar Yánez-Avalos ◽  
Juan Carlos Lépez Parra ◽  
Juan Carlos Moyano Tapia ◽  
Roberto Orlando Quinteros Pozo ◽  
Pablo Roberto Marini
Keyword(s):  
Corpus Luteum ◽  
Artificial Insemination ◽  
Follicular Development ◽  
Fixed Time ◽  
Dual Purpose ◽  
Significant Difference ◽  
Ecuadorian Amazon ◽  
Dual Purpose Cattle ◽  
The Moment

Fixed- time artificial insemination (IATF, in Spanish) in beef cattle has provided the use of genetically superior bulls in order to maximize the quality of calves. However, implementing this reproductive technique has proved to be difficult to apply in heifers nursing calves for several months of lactancy. An immediate solution to fertility decline of cattle includes the use of hormones. Some hormonal treatments have been developed which are able to control the moment of the first artificial insemination (IA) and the following inseminations in non- pregnant heifers as well as for the treatment of anestrus. The objective of this work was to evaluate two protocols with prolonged proestrus performing artificial insemination at fixed time at 60 or 72 hours in dual purpose cattle from the Ecuadorian Amazon. The study was held from October 2015 to October 2016. A total of 226 multiparious Brows Swiss cattle with nursing calves were inseminated at 60 (T1, n=115) and at 72 (T2, n=111) hours after removing the progesterone device., The conception rate for T1 was 61% (70/115) and for T2: 47% of pregnancy (52/111), showing significant differences (p≤0.05). The estrus was expressed on average by 70.8%, with no significant difference between the protocols (P = 3.15, p≥0.082), for T1 it was 76% (87/115) and for T2 of 65%. The follicular growth at the withdrawal of the progesterone device (T1: 9.53 ± 0.11 mm, T2: 9.87 ± 0.12 mm), the IATF (T1: 12.3 ± 0.12 mm; T2: 11.9 ± 0.12 mm), and the corpus luteum size (T1: 23.1 0.14±mm; T2:22.8 0.15 ±mm) did not show significant differences p≥0.5 between both protocols. It was concluded that both protocols did not show significant differences regarding follicular development at the time of withdrawal of the IATF device and the size of the corpus luteum size measured at day seven after withdrawal. However, the pregnancy rate was higher for the 60-hour protocol.

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