A total number of 136 pregnant ewes with the same age and parity were used in the present study. The experimental ewes reared during Arabic months or lunar months, from the 1 Gomady to Zol-hega, 1432 AH. The available data for each animal were obtained from the records of Sheep Farm, Project of Experimental Farms. Lambing season started at months, Shawal to Zol-hega. After lambing, the ewes wer...

A sustained-release multi-trace element/vitamin bolus has been devised for administration to ewes in advance of mating. Each bolus contained 5.3g Cu, 50mg Se, 90mg Co, 100mg I, 3.2g Mn and 4.7g Zn with 268x10(3) IU Vitamin A, 54x10(3) IU Vitamin D and 800 IU Vitamin E. About 50% of each nutrient is released during the first 6 weeks. Thereafter the release rate slows and over the remaining life ...

In the absence of livestock contact, recurring lamb mortality in bighorn sheep (Ovis canadensis) populations previously exposed to pneumonia indicates the likely presence of carriers of pneumonia-causing pathogens, and possibly inadequate maternally derived immunity. To investigate this problem we commingled naïve, pregnant ewes (n=3) with previously exposed rams (n=2). Post-commingling, all ew...

The adrenal and renal responses to similar increases in plasma angiotensin II (AII) were studied in chronically catheterized fetal lambs (112-131 days gestation: term 145 days) and adult nonpregnant sheep. The rate of AII infusion was adjusted to compare the effect of similar rises in plasma AII concentration between fetuses and adult ewes. Increases in plasma AII were associated with a decreas...

This experiment studied congenital transmission in sheep experimentally infected with oocysts of Toxoplasma gondii and reinfected at one of three stages of pregnancy. Twenty ewes were experimentally infected with T. gondii strain ME49 (day 0). After the T. gondii infection became chronic (IFAT≤512), the ewes were allocated with rams for coverage. After the diagnosis of pregnancy, these ewes wer...

The litter size of homozygous Booroola Merino ewes results in high perinatal mortality. One subcutaneous implant of crystaline oestradiol in silastic tubing in heterozygous Booroola Merino ewes decreased ovulation rate from 3.18 -r0.15 (n = 39) to 2.03 & 0.14 (n = 35), and decreased litter size (5 8 weeks pregnant) from 2.49 + 0.13 (n = 39) to 1.47 + 0.12 (n = 32), providing a useful management...

The first ovulation and first oestrus after parturition were recorded in four groups of Merino ewes which: (a) reared their lambs normally, (b) were allowed to suckle their lambs only during three 1-hr periods each day, (c) had their lambs removed on the day after birth, or (d) had their lambs removed on the day after birth and were injected intramuscularly with 5 i.u. oxytocin ten times each d...

This study investigated whether the transmission of naturally occurring scrapie in sheep can be prevented using embryo transfer. Embryos were collected from 38 donor ewes in a Suffolk sheep flock with a high incidence of naturally occurring scrapie, treated with a sanitary procedure (embryo washing) recommended by the International Embryo Transfer Society and then transferred to 58 scrapie-free...

Ewes were injected intramuscularly with 1 ml iodised oil at mating or during the first two months of pregnancy to determine if marginal iodine deficiency contributed to the high mortality of newborn lambs in Victoria. Iodine treatment markedly increased milk iodine concentration of ewes. In nine of ten trials conducted in 1979 and 1980 at Ararat, Hamilton, Langi Kal Kal, Ruffy, Rutherglen and T...