Sexual activity, body size and testis growth in the prepubertal period (120-210days of age) were studied in five male lambs of each of four dairy sheep breeds. Sexual responses developed earlier in Friesland than in Chios and Karagouniki and latest in Serres ram lambs. Friesland lambs expressed interest in females at 127days of age and 34kg live weight 18-36days younger and 3.4-6.3kg lighter th...

The objective of the present study was to compare live animal performance and carcass characteristics of 3/4 or 7/8 Dorper (DO; n= 30), purebred Katahdin (KA; n= 20), purebred St. Croix (SC; n= 17) and purebred Suffolk (SU; n= 10) lambs born in the spring and fall of 2001. After weaning, lambs were supplemented with up to 680 g of a corn-soybean meal supplement while grazing bermudagrass pastur...

Factors affecting ewe prolificacy (number of lambs born per ewe lambing) were evaluated using records on 9705 Targhee, 12,721 Suffolk, and 7231 Polypay lambings from flocks participating in the US National Sheep Improvement Program. Factors considered were ewe age and season of lambing. Prolificacy was affected by age of the ewe (P<0.001) and was highest for ewes lambing between 4 and either 7 ...

The objective of the study was to determine if exposure of young lambs to leafy spurge (Euphorbia e&u L.) would increase the consumption of this plant. Orphan lambs were exposed to leafy spurge from birth to 11 weeks of age as a water soluble extract mixed with milk replacer and as freshly harvested plants. Ewereared lambs were exposed to leafy spurge by grazing them on a leafy spurge-infested ...

Retroviral-mediated gene transfer was used to insert a Neo R gene into fetal sheep hematopoietic cells obtained by exchange transfusion from lambs in utero. After gene transfer the cells were returned to the donor fetus. The lambs were examined after birth for the presence of a functioning Neo R gene. Of ten analyzable animals, six were positive for G418 resistant progenitor cells (CFU-Mix, CFU...

This study was undertaken to investigate the occurrence and public health significance of Cryptosporidium species/genotypes and subtypes in a newborn lambs. A total of 175 diarrheic fecal samples from lambs (younger than 21 days) were collected in seven sheep flocks located in western Romania, and were microscopically examined for the presence of Cryptosporidium oocysts after staining with modi...

An experiment was conducted to study the effect of presence or absence of rumen ciliate protozoa on nutrient intake, its utilization, rate of body weight gain and feed conversion ef®ciency of lambs in post-weaning phase of growth. Forty ®ve weaned Malpura lambs, divided into three equal groups (G1, G2 and G3) were either defaunated by periodic dosing of sodium lauryl sulfate at the rate of 8 g/...

A three-year survey (1997-99) was carried out on organically reared sheep flocks throughout Sweden. The aim was to determine the prevalence and intensity of nematode infections and to establish relationships between sheep management practices and parasite infections. Faecal samples from ewes and lambs were collected from 152 organic flocks around lambing-time and during the grazing-period for a...

BACKGROUND A cornerstone of neonatal resuscitation teaching suggests that a rapid vagal-mediated bradycardia is one of the first signs of perinatal compromise. As this understanding is based primarily on fetal studies, we investigated whether the heart rate and blood pressure response to total asphyxia is influenced by whether the animal is in utero or ex utero. METHODS Fetal sheep were instr...

Results of the analysis are presented of the effect of inbreeding on selected reproduction traits and body weight in a Booroola flock kept closed for 14 years at the Institute of Genetics and Animal Breeding, Jastrzębiec. The mean inbred in lambs rose linearly until 2002, when it reached the level of 9.81%, ranging from 0 to 31.7%. No inbred effect was observed on ovulation rate, fertility, lit...