Crossbreeding can improve the profit for most dairy producers if economically similar breeds are used. However, it is important to stress that crossbreeding cannot replace pure breeding. Pure breeding is a prerequisite for crossbreeding. The heterosis obtained from crossbreeding is an added bonus on top of the genetic gain created by pure breeding. The size of the bonus depends on the number an...

The objective of this work was to evaluate the genetic diversity of Brazilian Pantaneiro horse by microsatellite markers, investigate the effect of genetic bottlenecks and estimate genetic differentiation among four horse breeds. Genetic variation was estimated through allele frequencies and mean breed heterozygosity. Nei ́s genetic distances among the breeds Pantaneiro, Thoroughbred, Arabian, S...

Yak are crossed with Bos taurus and Bos indicus cattle, including common local cattle breeds (via natural service) and via artificial insemination of frozen-thawed semen from improved breeds (e.g. Holstein Friesian). Female hybrids reach puberty and mate a year earlier than pure yaks. Nonpregnant F1 females usually have several estrus cycles in the same season and will generally calve every yea...

The role indigenous livestock can play in Africa’s Livestock Revolution is not always recognized. In many parts of Africa pure breeding with indigenous breeds is the only viable production strategy because of adverse climatic and nutritional conditions. However, there are scenarios where the higher demands of exotic breeds and their cross-breds can be met. This article discusses the possibility...

Weaning weights of calves of dams at ages in years of 2, 3, and older were modeled to be three separate traits. Fixed effects were sex of calf-year of birth combinations for nine pure breeds and sex of calf-year of birth-generation for three composite populations. Random effects fitted for each trait were correlated direct and maternal genetic, maternal permanent environmental, and temporary en...

Remarkably little has been published on hematological phenotypes of the domestic dog, the most polymorphic species on the planet. Information on the signalment and complete blood cell count of all dogs with normal red and white blood cell parameters judged by existing reference intervals was extracted from a veterinary database. Normal hematological profiles were available for 6046 dogs, 5447 o...

The serum or plasma biochemical profile is essential in the diagnosis and monitoring of systemic disease in veterinary medicine, but current reference intervals typically take no account of breed-specific differences. Breed-specific hematological phenotypes have been documented in the domestic dog, but little has been published on serum biochemical phenotypes in this species. Serum biochemical ...

Ewe performance was compared for five pure breeds of sheep (Finnsheep, F; Rambouillet, R; Dorset, D; Targhee, T; Suffolk, S) and the crosses in development of two maternal composite lines (C1 = 1/2F1/4R1/4D and C2 = 1/2F1/4T1/4S). The data involved 10,959 breeding season records of 4,219 ewes by 412 sires. Ewe production and the components (fertility, litter size, neonatal and preweaning lamb s...

BACKGROUND Sensitivity to macrocyclic lactones, which are commonly used in veterinary clinics, was first found in Rough Collies, and was attributed in 2001 to a 4 bp deletion in the MDR1 gene. The list of affected breeds currently includes 13 breeds. Researchers from different countries and continents examined the allelic frequencies of the nt230(del4) MDR1 mutation, emphasizing the clinical im...

The diaspora of the modern cat was traced with microsatellite markers from the presumed site of domestication to distant regions of the world. Genetic data were derived from over 1100 individuals, representing 17 random-bred populations from five continents and 22 breeds. The Mediterranean was reconfirmed to be the probable site of domestication. Genetic diversity has remained broad throughout ...