The effects of continuous sire selection on the structure and age composition of dairy cattle populations

1972 ◽  
Vol 15 (2) ◽  
pp. 103-110 ◽  
Author(s):  
C. J. M. Hinks
Keyword(s):  
Numerical Model ◽  
Dairy Cattle ◽  
Artificial Insemination ◽  
Progeny Test ◽  
Age Composition ◽  
Male And Female ◽  
Time Period ◽  
Breeding Programmes ◽  
Planning Problems ◽  
Sire Selection

SUMMARYA numerical model of male and female replacement processes is developed and used to construct a matrix which specifies the numbers of lactations of different parities expressed in a given time period by daughters of bulls used in artificial insemination (AI).Populations resulting from newly established AI breeding programmes contain an unduly high proportion of offspring by young bulls. Subsequently an equilibrium is reached in which offspring of young and tested bulls are present in proportions determined by the relative usage of the two types of sire and by differences in replacement rates amongst their progeny. Once an equilibrium has been reached the numbers of progeny sired by bulls lacking a progeny test proof is extremely small.The use of the technique to solve a number of specific planning problems is demonstrated.

Cattle transferrins and milk production

1967 ◽  
Vol 9 (4) ◽  
pp. 491-500 ◽  
Author(s):  
Alan Jamieson ◽  
Alan Robertson
Keyword(s):  
Genetic Variation ◽  
Great Britain ◽  
Dairy Cattle ◽  
Milk Production ◽  
Milk Yield ◽  
Opposite Direction ◽  
Artificial Insemination ◽  
Fat Content ◽  
Progeny Test ◽  
Cattle Breeds

1. An analysis has been made of the association between transferrin genotype and progeny test for both milk yield and fat content in a sample of 879 bulls of five dairy cattle breeds, the majority used in artificial insemination in Great Britain. Although significant effects were found in only one of the ten analyses when the breeds were considered separately, a significant effect on milk yield was found when the results from all breeds were combined. A significant effect was not found for fat content, although the effects of the allele substitutions were in the opposite direction to that on milk yield in five cases out of six.2. Although our results were in the same direction as those of Ashton, the effects were smaller. It was estimated that the locus accounted for 1·1% of the genetic variation in yield and 0·4% of the genetic variation in fat content.3. Some information based on the production records of 178 experimental cows with known genotypes was also analysed. For milk yield, the pattern of effects was similar to that in the sire data though the differences were much larger. The variance removed by fitting constants was not statistically significant for milk yield or fat content. It was estimated that the sire data contained some fifty times as much information as did the cow data.

Application of reproductive technology to the Australian livestock industries

1991 ◽  
Vol 3 (6) ◽  
pp. 627 ◽  
Author(s):  
G Evans
Keyword(s):  
Artificial Insemination ◽  
Management Practices ◽  
Significant Degree ◽  
Reproductive Technology ◽  
Commercial Application ◽  
Embryo Freezing ◽  
Commercial Practice ◽  
Breeding Programmes ◽  
The Impact

Current use of reproductive technology in the Australian livestock industries is limited, though it increased in line with higher prices for beef and wool through the 1980s. The required techniques, many of which were developed in Australia, are available and the level of expertise is comparable to the best in the world. However, the extensive pastoral industries do not readily lend themselves to these procedures. Only in the dairy industry is artificial insemination used to a significant degree. On the other hand, application of the technology in the pastoral industries is confined largely to studs and breeding cooperatives which provide breeding animals for producer flocks and herds. Hence the impact of applied technology may be more widespread than first appears. Until recently, little regard was paid to application of the technology along sound breeding principles. Artificial insemination and multiple ovulation and embryo transfer (MOET) have not been used so much in planned breeding programmes aimed at local improvement of stock, but more to proliferate genes of reputedly superior stock, imported either from overseas or elsewhere in Australia. This is particularly true of MOET, where the incentive to use it is commonly a short term cash gain made from proliferating breeding stock of a particularly valuable and usually novel strain or breed. Recent technological improvements which render the use of reproductive technology cheaper and more effective will lead to its more widespread use in commercial practice. Techniques for embryo freezing and splitting have been greatly simplified and quickly put into practice. The novel livestock technologies of in vitro oocyte maturation and fertilization have already found commercial application overseas. Fecundity-enhancing products have also been adopted by the livestock industries. There is potential value for greater use of reproductive technology in the livestock industries provided it is implemented according to sound breeding principles and provided associated management practices are applied simultaneously.

scholarly journals Genetic Basis of Mastitis Resistance in Dairy Cattle – A Review / Podstawy Genetyczne Odporności Krów Mlecznych Na Zapalenie Wymienia – Artykuł Przeglądowy

2013 ◽  
Vol 13 (4) ◽  
pp. 663-673 ◽  
Author(s):  
Grażyna Sender ◽  
Agnieszka Korwin-Kossakowska ◽  
Adrianna Pawlik ◽  
Karima Galal Abdel Hameed ◽  
Jolanta Oprządek
Keyword(s):  
Dairy Cattle ◽  
Association Studies ◽  
Genetic Resistance ◽  
Clinical Mastitis ◽  
Future Research ◽  
Complex Nature ◽  
Candidate Gene Approach ◽  
Genome Wide Association Studies ◽  
Polygenic Control ◽  
Breeding Programmes

Abstract Mastitis is one of the most important mammary gland diseases impacting lactating animals. Resistance to this disease could be improved by breeding. There are several selection methods for mastitis resistance. To improve the natural genetic resistance of cows in succeeding generations, current breeding programmes use somatic cell count and clinical mastitis cases as resistance traits. However, these methods of selection have met with limited success. This is partly due to the complex nature of the disease. The limited progress in improving udder health by conventional selection procedures requires applying information on molecular markers of mastitis susceptibility in marker-assisted selection schemes. Mastitis is under polygenic control, so there are many genes that control this trait in many loci. This review briefly describes genome-wide association studies which have been carried out to identify quantitative trait loci associated with mastitis resistance in dairy cattle worldwide. It also characterizes the candidate gene approach focus on identifying genes that are strong candidates for the mastitis resistance trait. In the conclusion of the paper we focus our attention on future research which should be conducted in the field of the resistance to mastitis.

scholarly journals A Sociolinguistic Study of Choosing Names for Newborn Children in Jordan

2016 ◽  
Vol 6 (1) ◽  
pp. 177 ◽  
Author(s):  
Abeer Harb Al-Qawasmi ◽  
Fawwaz Al-Abed Al-Haq
Keyword(s):  
Random Sample ◽  
Social Values ◽  
Male And Female ◽  
Personal Names ◽  
The People ◽  
Time Period ◽  
Civil Status ◽  
The Difference ◽  
Different Cultures ◽  
Clear Change

<p>This study aims at the study of newborn names in Jordan of a sociolinguistic perspective. This study tries to detect the difference in naming newborns in Jordan over the decades - from the seventies to 2015 due to the result of some factors that may have affected the Jordanian society, whether historical, religious and/or social. The data necessary to complete the study was obtained from the Civil Status Department and the Department of Statistics. The data obtained consisted of names of both sexes during the time period from the seventies until the early year of 2015, a random sample of personal names within the same family were also provided. The data was analyzed quantitatively. The study revealed that there is a clear change in the choice of newborn names-male and female-in Jordan, whether a change in sounds or in morphemes. In specific, names during the seventies were strongly linked to the culture and the values, religious or social, in which the people believed in. During the eighties and nineties, names were associated with certain social values, however, some names were shown to be affected by urbanization or modernization. And with the beginning of 2000 up to 2015, peoples directions towards naming newborns changed due to the advent of globalization, associating with development and urbanization, and moreover, the influence of different cultures on the community.</p>

scholarly journals Costs and Risks for Sire Selection Strategies in Artificial Insemination

1981 ◽  
Vol 64 (3) ◽  
pp. 491-496 ◽  
Author(s):  
M. Schneeberger ◽  
A.E. Freeman ◽  
P.J. Berger
Keyword(s):  
Artificial Insemination ◽  
Selection Strategies ◽  
Sire Selection

scholarly journals Non-specific Bacterial Profiles in Reproductive Tract of Dairy Cattle during Artificial Insemination

2021 ◽  
Vol 11 (1) ◽  
pp. 110-114
Author(s):  
Astin Islam Andriani ◽  
Sri Pantja Madyawati ◽  
Emy Koestanti Sabdoningrum
Keyword(s):  
Dairy Cattle ◽  
Bacterial Infection ◽  
Artificial Insemination ◽  
Reproductive Tract ◽  
The Other ◽  
Reproductive Efficiency ◽  
Reproductive Disorders ◽  
Bacterial Isolation ◽  
Isolation And Identification ◽  
Other Hand

One of the causes of low reproductive efficiency in dairy cattle is the presence of reproductive disorders caused by a non-specific bacterial infection. The aim of the present study was to isolate and identify the genus of non-specific bacteria in the reproductive tract of dairy cattle during artificial insemination. A total of 10 samples in the form of mucus attached to the plastic sheath used after artificial insemination in dairy cattle were collected in the study. The samples were subjected to bacterial isolation and identification. The obtained results of the study indicated that Staphylococcus was the dominant genus found (90%). On the other hand, other genera were Escherichia (60%) and Corynebacterium (20%).

The use of progeny testing with artificial insemination in dairy cattle

1950 ◽  
Vol 50 (1) ◽  
pp. 21-31 ◽  
Author(s):  
Alan Robertson ◽  
J. M. Rendel
Keyword(s):  
Dairy Cattle ◽  
Artificial Insemination ◽  
Progeny Testing

Methods for assessing sociability of dairy cows

2007 ◽  
Vol 2007 ◽  
pp. 38-38
Author(s):  
J. Gibbons ◽  
A. B. Lawrence ◽  
M. Haskell
Keyword(s):  
Individual Differences ◽  
Dairy Cattle ◽  
Dairy Cows ◽  
Social Behaviour ◽  
Social Motivation ◽  
Welfare Assessment ◽  
Suitable Test ◽  
Breeding Programmes ◽  
Social Companionship ◽  
Reliable Methods

Sociability refers to the extent to which animals seek social companionship. Individual differences in social behaviour exist between animals. It is important to measure individual social motivation in order to develop suitable temperament scores that can be used in future breeding programmes or as part of welfare assessment schemes. Runway tests have been shown as reliable methods of measuring sociability in animals (Birds Mills & Faure, 1991; Sheep Sibbald et al., 2005). The aim was to develop a suitable test that could be used to measure sociability of cows in a commercial situation. The following questions were addressed i) How repeatable is the runway test when carried out on dairy cattle, ii) Does a cow’s performance in a runway test correlate with social behaviour within a group house setting?

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