Paraquat (PQ) is used as a herbicide in agriculture and causes oxidative and inflammatory damage to animal tissues. The current study was conducted to investigate the positive effects of dietary propolis (PR), as a potent naturally produced antioxidant, on growth performance and immune function of turkey poults exposed to oxidative stress induced by PQ injection. Native male turkey poults (n = 120, 49-d-old) were randomly assigned into 4 groups: poults received a basal diet with a daily subcutaneous PQ injection of 5 mg/kg BW for 7 consecutive days (PQ group), an experimental diet containing 1 g/kg PR with a daily subcutaneous PQ injection for 7 days (PR+PQ group), or received the experimental PR diet with a daily subcutaneous injection of 0.5 mL sterile saline for 7 days (PR group); while the control poults received a basal diet with a daily subcutaneous saline injection for 7 consecutive days (C group). The productive performance in the PQ group showed a significant (P < 0.05) reduction in the weight gain (WG) and feed intake (FI), and impaired feed conversion ratio (FCR). Propolis supplementation in the PR+PQ group significantly ameliorated the PQ effects on WG and FCR. Turkey poults of the PQ and PR+PQ groups had a significant augmentation in the blood malondialdehyde (MDA), tumor necrosis factor-α (TNFα), and corticosterone levels, and in contrast, a significant reduction in the triiodothyronine (T3), when compared to the C group. While propolis significantly reduced the MDA and corticosterone, and increased the T3 levels in the PR+PQ group compared to the PQ group. Furthermore, the dietary PR supplementation significantly limited the PQ-suppressive effects on cell- and humoral-mediated immunity and lymphocyte proliferation of turkey poults. In addition, propolis supplementation in the PR and PR+PQ groups markedly reversed the PQ-induced DNA fragmentation and heat shock protein 70 (Hsp70) over-expression in blood cells. It can be concluded that PR could improve turkey immunity and performance, particularly under inflammation and oxidative stress induced by PQ exposure.

Estimation of genetic and phenotypic parameters of productive (305-day yields of milk, MY305; fat, FY305 and protein, PY305) and reproductive performance traits (days open, DO; calving interval, CI and number of inseminations per conception, NSC) were calculated on 3398 lactation records of 1054 Holstein Friesian cows, daughters of 94 bulls and 691 dams using multi-trait animal model with repeated records. Expected impact of direct selection for MY305, FY305 and PY305 on reproductive performance was calculated. Heritability estimates for productive traits varied from 0.08 to 0.26 and from 0.04 to 0.19 for reproductive traits. The productive traits were highly inter-correlated genetically (0.995 to 0.998) than the reproductive traits (0.241 to 0.786). Cows which producing abundant MY305, FY305 and PY305 tended to show less reproductive efficiency in terms of longer DO (r G = 0.942 to 0.947), longer CI (r G =0.587 to 0.673) and more NSC (r G =0.769 to 0.829). Direct selection, after one round of selection, for MY305, FY305 and PY305 is expected to result in cows with more advantageous productive performance in terms of higher MY305 (+180.22 to 323.27 kg), FY305 (+13.79 to 24.95 kg) and PY305 (+12.41 to 22.48 kg). This enhancement in productive performance is expected to be associated with deterioration in reproductive performance in terms of longer days open (+16.27 to 29.48 days), longer calving interval (+15.26 to 25.22 days) and higher number of inseminations per conception (+.08 to 0.16 services). It could be concluded that the undesirable relationship between productive and reproductive performance traits in Holstein Frisian cows must be taken into consideration when planning breeding programs in dairy cattle (e.g. improving productive traits by genetic selection and reproductive traits by enhancement management or by using restricted selection indices).

The aim of this study was to in-vitro evaluate encapsulated probiotic supplementation to ruminant rationson degradation and fermentation parameters. The ration consisted of 40% alfalfa hay and 60% concentrate feed mixture. Encapsulated and not encapsulated probiotic were supplemented with level of 10 6 cfu/kg of the total dry matter of ration (DM) and compared with encapsulation media (Sodium Alginate, SA) and control (not supplemented ration). DM and OM degradation and total gas production as well as fermentation parameters of the incubated samples were determined after 24 h of fermentation. Significant (P<0.01) increases in in-vitro DM degradability was observed for the experimental ration supplemented with encapsulated or not encapsulated probiotics at levels (10 6 CFU/ kg DM) and SA treatment compared to control ration. Also, significant (P<0.05) improvement in OM degradability was recorded for the ration supplemented with not encapsulated probiotics bacteria compared to the other treatments. Moreover no significant differences were observed between the control ration and the rations supplemented with encapsulated probiotics or SA only, as well as no significant difference was recorded between the ration supplemented with encapsulated probiotics and the ration supplemented with SA only. Probiotics bacteria supple-mentation in the form of not encapsulated probiotic resulted significant increases in in vitro total gas production per sample and per g DM, OM, dDM, NDF and ADF after 24 hours incubation period compared to the other experimental rations (control, encapsulated probiotic and SA). While significant increase in total gas production per g dOM was observed for not encapsulated probiotic compared to encapsulated probiotic only. It could be concluded that, using encapsulated probiotics bacteria had no significant effect on DM degradability and may be induce decrease in gas production and fermentation parameters.

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Genetic and phenotypic parameters of productive (305-day yields of milk, MY; fat, FY and protein, PY) and reproductive (days open, DO; number of service per conception, NSC and age at first calving, AFC) traits were estimated from 1180 first lactation records on Holstein dairy cows, daughters of 93 sires and 650 dams, using multi-trait animal model. Seven selection indexes aiming to improve 305-day yields of milk, fat and protein were considered using various combinations of these three traits as sources of information. The full index (I 1), being the most accurate index, had the highest correlation with the true breeding value (r TI = 0.629). Comparable accuracy (r TI = 0.607) would be expected from the single trait index involving milk yield alone. At each round of selection, such a single trait index is expected to result in advantageous productive traits in terms of higher yields of milk (+727.24 kg), fat (+22.10 kg) and protein (+20.68 kg), and disadvantageous reproductive performance in terms of DO (+4.41 day), NSC (+0.01 service) and AFC (+0.15 month). To prevent deterioration in DO, NSC and AFC, separate restrictions were imposed to the full index (I 8(DO) , I 9(NSC) and I 10(AFC) respectively). The optimum balance between production and fertility was obtainable via using (I 9(NSC)) instead of I 1 with slight reduction in accuracy of selection (r TI = 0.590 vs. 0.629) and in expected gain in yields of fat (20.60 vs. 25.12 kg) and protein (19.36 vs. 23.63 kg) but with seemingly tolerable sacrifice in milk yield gain (709.13 vs. 774.07 kg).