The aim of the study was to determine the production responses of lambs receiving either creep feed or not while grazing two different pastures. The production of ewes within each treatment was also recorded. The study was conducted at both the Kromme Rhee and Langgewens Research Farms. At Kromme Rhee, sheep grazed kikuyu (Pennisetum clandestinum) pasture under irrigation. Dohne Merino (n = 47) ewes, with their lambs, were randomly allocated to four groups. At Langgewens, the sheep grazed medic (Medicago parrabinga) pastures under dry-land conditions. South African Mutton Merino ewes (n = 89), with their lambs, were randomly divided into four groups. At Langgewens creep feed was provided at 200 g/lamb/day from the start of the study. This was increased by 100 g/lamb/day every week up to a maximum of 600 g/lamb/day. At Kromme Rhee, creep feed was provided at 200 and 300 g/lamb/day for the first and second week, respectively. From week three creep feed was provided ad libitum. At both locations ewes and lambs were weighed once a week. Live weight data of lambs and ewes were analysed by means of a multifactor analysis of variance with treatment (creep feed or no creep feed) and birth status (single and twins) as main factors. Provision a creep feed at Langgewens significantly increased lamb weight, but had no effect on ewe live weight. The provision of creep feed At Kromme Rhee significantly increased lamb weight as well as ewe weight. At both locations, birth status had no effect on the production parameters for ewes or lambs.

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Ram seminal plasma increases the fertility of frozen-thawed ram spermatozoa deposited into the cervix. The aim of the current study was to compare the effect of ram seminal plasma to that of bull seminal plasma, dog prostatic fluid, protein-free TALP, TrilEq (Triladyl with 0.5 mℓ of Equex STM paste added to each 100 mℓ) and heat-treated skim milk on longevity and percentages of progressively motile and aberrantly motile frozen-thawed ram spermatozoa. Three ejaculates from each of 6 rams were extended in TrilEq, pooled and frozen in straws as a single batch per ram. One hundred and eight straws (3 straws from each ram for each fluid) were thawed in random order. Once thawed, a straw was emptied into a tube with 0.85mℓ of the appropriate fluid at 37 °C and kept at that temperature for 6 h. Motility was assessed at x200 magnification immediately (time zero) and 2, 4 and 6 h after thawing. Progressive motility decreased from each time to the next (P < 0.05) and was 39.0% (0 h), 26.0% (2 h), 19.6% (4 h) and 12.6% (6 h); SEM 1.24, n=108 for each group. Ram seminal plasma resulted in higher progressive motility than bull seminal plasma, lower than milk, and similar to the other fluids. Ram seminal plasma resulted in lower aberrant motility than protein-free TALP and similar aberrant motility to other fluids. The effect of ram seminal plasma and dog prostatic fluid was very similar. The effect of ram seminal plasma on the fertility of frozen-thawed ram spermatozoa deposited into the cervix is not due an exceptionally beneficial effect on the motility of spermatozoa

No abstract