Puberty Studies of Swedish Crossbreeding Gilts*

Effect of elevated ambient temperatures on puberty in gilts.

Effects of elevated ambient temperature on puberty and related physiological responses were studied in 40 gilts. Group 1 (n = 20) gilts were born in September and Group 2 (n = 20) gilts were born in March. Gilts were placed in environmentally controlled chambers at 140 d of age. After a 10-d acclimation period at 20 degrees C, 35% relative humidity (RH), and 12 h light (L)/12 h dark (D), gilts ...

Influence of nutritional regime on age at puberty in gilts.

Endocrine changes and management factors affecting puberty in gilts

Puberty in gilts is the occurrence of first oestrus and the onset of reproductive capability (usually at between 200 and 220 days of age). It is the combined effect of genetic factors and management factors (including nutrition, boar exposure and season) that contribute to the age at puberty. Consumer demands for leaner pork have lead to genetic selection for increased lean tissue growth rate a...

Ovarian activity and uterus organometry in delayed puberty gilts.

About 30% of the total number of gilts selected for reproduction at the large breeding farm units in Vojvodina (Republic of Serbia) are culled due to prolonged pre-insemination anoestrus (estrus not detected until 8 mo of age). The aim of this study was to provide the answer to the following question: do the culling gilts reach cyclic ovarian activity at all? One hundred seventy five culled gil...

Factors influencing age at first mating in purebred Swedish Landrace and Swedish Yorkshire gilts.

The aim of the present study was to retrospectively analyze causes of the variation in age at first mating in Swedish Landrace (L) and Swedish Yorkshire (Y) gilts. Production traits including growth rate from birth to 100kg body weight and backfat thickness at 100kg body weight were also studied. Data analyzed were obtained from 11 L and 11 Y nucleus herds and included gilts born during a 5-yea...