Chromosomal anomalies in dairy cattle as reasons of impaired fertility

Abstract

Aim. The evaluation of animals for the presence of chromosomal anomalies is one of the main tasks of prac- tical selection, aimed at detecting undesired chromosomal anomalies in early age, which may have negative impact on the reproductive and productive capability of cows and lead to considerable economic losses. The aim of the work is a cytogenetic analysis of the chromosome set in cows of Ukrainian Red-and-Motley dairy cattle breed, which will allow assuming a decrease in reproductive functions with chromosomal aberrations. Methods. We examined 53 cows of the Ukrainian Red-and-Motley dairy cattle breed in SE Research Farm Khrystynivske, IABG named after M.V. Zubets, NAAS. The investigation of chromosomal anomalies involved 72-h cultivation of lymphocytes from the peripheral blood of animals using the common methods. During a routine analysis the preparations were stained with 2 % Giemsa staining solution. The induction of G-bands for differential staining of chromosomes was conducted using 0.25 % solution of trypsin. The processing of study results was performed with Microsoft Excel software package. Results. The investigations in the aberration spectrum detected aneuploid and polyploid cells, breaks and fragments of chromosomes, premature chromo- some disjunction in mitosis and translocation. The total number of aberrant cells in cows with decreased fertil- ity was 14.69 ± 0.56 %, the number of aberrations per one investigated cell was 0.144, which was almost twice reliably (Р < 0.999) exceeding the values of similar features for cows which did not have problems with repro- duction. GTG-banding method was used to detect a new RT 13/23 Robertsonian translocation. Conclusions. The cytogenetic analysis of chromosome set of Ukrainian Red-and-Motley dairy breed cows allows assuming the connection between a decrease in the fertility of cows and chromosomal instability. A routine screening of dairy cows allows both evaluating the karyotype saturation with undesired chromosomal aberrations and using the obtained results to forecast the reproductive ability of an animal in the early age.

Effect of Selected Micro- and Macroelements and Vitamins on the Genome Stability of Bovine Embryo Transfer Recipients following In Vitro Fertilization

“…Studies assessing genome stability in cows used in assisted reproduction, e.g., in vitro fertilization, can make it possible to evaluate and select the best cows, i.e., those with high genome stability. Studies analyzing chromosomal instabilities in cattle most often focus on numerical and structural mutations in chromosomes [ 3 , 68 , 69 , 70 ]. There are fewer studies on chromosomal instabilities resulting from errors in replication, transcription, or malfunctioning repair mechanisms and control points tasked with catching these errors.…”

Assessment of the genomic stability of calves obtained from artificial insemination and OPU/IVP in vitro fertilization

“…Studies detecting chromosomal instabilities in cattle most often analyse structural and numerical anomalies (Dzitsiuk & Tipilo, 2019;El-Bayomi et al, 2011;Jennings et al, 2020;Trukhachev et al, 2017).…”

“…Chromosomal instabilities can cause disturbances at the level of cell function (Wójcik et al, 2018; Wójcik & Szostek, 2019). Studies detecting chromosomal instabilities in cattle most often analyse structural and numerical anomalies (Dzitsiuk & Tipilo, 2019; El‐Bayomi et al, 2011; Jennings et al, 2020; Trukhachev et al, 2017). There are fewer reports on the types of chromosomal instabilities identified by the SCE, FS or comet assays, which result from errors in replication and in malfunctioning repair mechanisms and checkpoints.…”

Identification of Genomic Instability in Cows Infected with BVD Virus

“…Genetic tests, especially cytogenetic assays, are helpful tools for assessing genomic stability and integrity. Many chromosome instabilities reduce fertility in cows [84][85][86][87][88][89], and structural and numerical mutations are among the instabilities which cause reproductive problems [89][90][91][92]. Scientists are increasingly assessing the genomic stability using cytogenetic assays, which identify chromosome instability arising as a result of malfunctioning cellular mechanisms, such as replication, transcription, damage repair, and checkpoints [93][94][95].…”