Selection signatures associated with adaptation in South African Drakensberger, Nguni, and Tuli beef breeds.

In the present study 1,709 cattle, including 1,118 Drakensberger (DRB), 377 Nguni (NGI), and 214 Tuli (TUL), were genotyped using the GeneSeek® Genomic Profiler™ 150 K bovine SNP panel. A genomic data set of 122,632 quality-filtered single nucleotide polymorphisms (SNPs) were used to identify selection signatures within breeds based on conserved runs of homozygosity (ROH) and heterozygosity (ROHet) estimated with the detectRUNS R package. The mean number of ROH per animal varied across breeds ranging from 36.

Brainstem auditory evoked responses: Objective hearing threshold assessment in Holstein cows.

Background:  Animal audiology utilizes brainstem auditory evoked responses (BAER) as a non-invasive tool to assess hearing in animals, including Holstein dairy cows. Understanding cows' auditory capabilities is critical for their welfare, especially given their exposure to farm noise.

Objectives:  This study provides preliminary normative BAER data for Holstein cows by focusing on absolute and interpeak wave latencies.

The impact of myostatin variants on growth traits in South African Bonsmara beef cattle.

Double muscling occurs when the myostatin (MSTN) gene is deactivated due to a series of mutations, leading to uncontrolled muscle growth and excessive muscle fiber accumulation, as the gene can no longer effectively regulate muscle development. This study aimed to assess the impact of MSTN variants and their combinations on growth traits, namely direct birth weight (BW), direct weaning weight (WW), average daily gain (ADG) and feed conversion ratio (FCR) in the South African (SA) Bonsmara. Genomically enhanced estimated breeding value (GEBVs) for traits of interest, and MTSN genotypes for SA Bonsmara animals were available for the study.

Risk factors underlining reproductive performance in smallholder beef cattle herds of South Africa.

Improving the historically low reproductive performance of beef cattle in smallholder systems is essential for its productivity and profitability. Therefore, identifying and addressing risk factors associated with low performance in this system present an opportunity for improvement. The study aimed to evaluate the effect of animal and management risk factors on pregnancy rate (PR), fetal and calf loss (FC), calving interval (CI) and days open (DO) in smallholder beef cattle farms.

Automated Cow Body Condition Scoring Using Multiple 3D Cameras and Convolutional Neural Networks.

Body condition scoring is an objective scoring method used to evaluate the health of a cow by determining the amount of subcutaneous fat in a cow. Automated body condition scoring is becoming vital to large commercial dairy farms as it helps farmers score their cows more often and more consistently compared to manual scoring. A common approach to automated body condition scoring is to utilise a CNN-based model trained with data from a depth camera.