The developmental capacity of (a) single blastomeres of 4-cell embryos, (Jb) pairs of blastomeres of 8-cell embryos and (c) single blastomeres of 8-cell embryos was studied. The blastomeres were inserted into evacuated foreign zonae pellucidae, embedded in agar, transferred to ligated oviducts of dioestrous ewes, and recovered when their total age was 5-Jto 6̂ days. At lecovery the majority of e...

The developmental capacity of (a) single blastomeres of 4-cell embryos, (Jb) pairs of blastomeres of 8-cell embryos and (c) single blastomeres of 8-cell embryos was studied. The blastomeres were inserted into evacuated foreign zonae pellucidae, embedded in agar, transferred to ligated oviducts of dioestrous ewes, and recovered when their total age was 5-Jto 6̂ days. At lecovery the majority of e...

Thirty-two Afshari lambs were used in a completely randomized design with a 2 × 2 factorial arrangement of treatments to evaluate a nutritional supplement designed to provide multiple gluconeogenic precursors during heat stress (HS). Lambs were housed in thermal neutral (TN) conditions and fed ad libitum for 8 d to obtain covariate data (period 1 [P1]) for the subsequent experimental period (pe...

The objective of this study was to investigate the effect of maintenance system as well as the effect of Se, Zn, and vitamin E supplementation of ram-lambs on the slaughter value and concentration of mineral elements in the loin muscle of lambs. The experiment was conducted on 72 Polish Merino ram-lambs divided into three groups: group C, indoor with no supplement, 19 lambs; S, indoor with supp...

The effects of Spirulina supplementation, sire breed, sex and basal diet on intramuscular fat percentage (IMF) and fat melting point (FMP) in crossbred and purebred Merino lambs were investigated. Over two consecutive years, a total of 48 lambs was randomly allocated into feeding trials that utilised either ryegrass or Lucerne hay basal diets. Each treatment group had 8 lambs balanced by sire b...

In order to determine the efficacy of melatonin implants in initiating the lambing season and improving reproductive efficiency in sheep, ewes (n= 1932) from three breeds (Rasa Aragonesa, Assaf and Merino) received melatonin implants (Group M) every 45 days from the winter solstice (1 January and 15 February—winter; 1 April and 15 May—spring) on 12 commercial farms. The other group of ewes (n= ...

The experiment was conducted on 80 Polish Merino ewes, their 82 lambs and 40 fattening rams. Merino ewes were divided into two groups: experimental (E) and control (C), each composed of 40 animals. Four weeks before lambing, 1 day, 3 weeks and 6 weeks after lambing 40 ewes of the experimental (E) group received intramuscular injection of 5 ml 0.1 % Na2SeO4 (selenium [Se]: 2.09 mg), 10 ml 10 % Z...

Lambs were used to evaluate the effect of acute heat stress (HS) or restraint and isolation stress (RIS) on endocrinological and immunological functions. In Exp. 1, lambs were exposed to HS (35 degrees C) and control lambs (CN) were exposed to 21 degrees C for 24 h in two replicates (n = 8 lambs total per treatment). Samples of serum were obtained at frequent intervals for evaluation of cortiso...

The study was conducted on 20 Polish Merino ram-lambs divided into two groups: experimental (E) and control (C), each of 10 animals. From birth all the lambs were maintained with their dams and then weaned at the age of 8 weeks, placed in individual straw-bedded pens and fattened individually with a granulated concentrate mixture until reaching a mean body weight of 31.8 kg. During fattening ea...

background: high grain diets in ruminants increases the risk of digestives disorders such as acidosis which may lead to high economic loss. objectives: this experiment was conducted to determine the effects of an unsaturated and polyunsaturated fatty acid and monensin on gene expression of enzymes involved metabolic pathway of cell proliferation and rumen epithelial intracellular ph regulation....