Ronald O. Bates Michigan State University

Publish Date: November 14, 2014

Due to specific state legislation or market requirements many farms will have to house gestating sows in groups. Management practices will have to be modified for farms to be successful when housing sows in groups during gestation. Gilts and sows have a dominance hierarchy based on aggression and avoidance. Fighting among sows mainly occurs during the first 2 to 3 hours after mixing. The hierarchy is primarily established within 24 hours. An important consideration will be how to mix sows and gilts in groups to reduce overall, prolonged aggression. This article will provide guidelines that can be used to formulate standard operating procedures for mixing sows into gestation pens. For this ‘How-To’ sheet, it will be assumed that females (gilts and sows) will be mixed after they are mated.

Publish Date: June 3, 2006

Ultrasonic measurement is a viable method to estimate backfat thickness and loin muscle area in the live pig. However accuracy of ultrasonic estimates are technician dependent. The National Swine Improvement Federation (NSIF) has implemented programs to standardize ultrasonic measurement for these traits. These programs consist of a workshop and training session a scanning practicum for participants and a written exam. Participants will be evaluated for their ability to predict carcass data, repeatability of their measurements and bias of live measurements as compared to carcass data. Persons that receive NSIF certification status must meet or surpass NSIF standards.

Publish Date: June 3, 2006

The swine industry is re-emphasizing the importance of efficiently developing a quality product. To fulfill this objective, market hogs will need to come from larger litters and convert feed into lean meat more efficiently. For this to occur in your herd, favorable genetic change needs to be made in those traits that effect efficiency of production. Therefore, pork producers need to understand basic genetic concepts so that they can apply them to improve economically important traits.

Publish Date: June 3, 2006

Recording performance data is common place within many swine businesses in the United States. Information such as sow farrowing and weaning data and changes in feed and pig inventories are used regularly for both tactical and strategic planning.

Publish Date: June 3, 2006

In estimating the genetic merit of an animal, breeders are trying to determine the animal’s value as a parent, its breeding value. The phenotype of an animal (the traits we see and measure) is a combination of genetic and environmental effects. Genetic effects are the result of the genes inherited from parents. Environmental effects are the result of conditions the animal experienced, such as level of nutrition, stocking density, temperature, or health status.

Publish Date: June 3, 2006

Correct use of selection concepts is essential if genetic improvement is to proceed at a rapid rate. Therefore, seedstock breeders and commercial pork producers need to fully understand the principles of selection which directly influence the amount of genetic improvement made per year. This fact sheet explains the primary concepts necessary to gain an understanding of genetic improvement. Then it discusses the effect of applying selection concepts on genetic improvement.