The present study aimed to investigate the long-term effect of feeding barley grain steeped in lactic acid (LA) with or without thermal treatment on reticuloruminal pH dynamics and metabolic activity of the liver in 12 primiparous and 18 multiparous early-lactating dairy cows. All cows were included on d 21 postpartum and sampled until d 90 postpartum. Cows were fed a diet based on differently processed ground barley grain: untreated grain (control diet, CON), or grain treated with 1% LA alone for 24 h before feeding (LA), or with an additional oven-heating at 55°C for 12 h (LAH). The reticuloruminal pH and temperature were measured via indwelling sensors that allowed for continuous (every 10 min) and long-term measurement from d 21 to 80 postpartum. Blood samples were taken on d 21, 40, and 90 of lactation and analyzed for liver enzymes aspartate aminotransferase (AST), gamma-glutamyltransferase, and glutamate dehydrogenase, as well as bilirubin, bile acids, and serum amyloid A. Dry matter intake was higher in multiparous cows (20.7 ± 0.27 kg/d) compared with primiparous cows (18.2 ± 0.33 kg/d), but was not affected by dietary treatment. Overall, the relatively short duration (51 ± 5 min/d) of reticuloruminal pH 5.8 suggests low risk of subacute ruminal acidosis throughout the experiment. Results indicated that LA treatment of barley, with or without heat, lowered the time duration of pH 5.8 compared with CON, but only in primiparous cows (from 118 ± 13 to 46 ± 11 and 25 ± 11 min/d for CON, LA, and LAH, respectively). In multiparous cows, the opposite effect of feeding the LA-treated barley on time duration of pH 5.8 (11 ± 8 vs. 46 ± 9 vs. 57 ± 9 min/d for CON, LA, and LAH, respectively) was observed. Multiparous cows generally showed higher pH readings and shorter periods in which the ruminal pH dropped below the threshold of pH 5.8. The reticuloruminal temperature was not affected by dietary treatment, whereas parity affected the time duration of reticuloruminal temperature >39.5°C, being 60 ± 19 min/d shorter in primiparous cows. The measured activities of the liver enzymes AST, gamma-glutamyltransferase, and glutamate dehydrogenase, as well as bilirubin, bile acids, and the acute phase protein serum amyloid A, were not affected by grain feeding. Additionally, only one small effect of parity on investigated serum variables was noticed, showing slightly but significantly higher values of AST in multiparous (80.5 ± 1.4 U/L) compared with primiparous cows (76.0 ± 1.7 U/L). In conclusion, our results indicate greater risk for primiparous cows to develop subacute ruminal acidosis-like conditions during early lactation than multiparous cows. The study also suggests limited benefits of feeding processed barley grain with LA with or without thermal treatment to modulate ruminal tolerance of grain feeding, whereby differing effects in primiparous cows were observed compared with multiparous cows

This experiment was conducted to evaluate the effects of dietary supplementation of greenBrazilian propolis on behavioral patterns and feather condition of heat stressed broilerchickens. Five hundred and four (504) male Ross 708 broiler chicks at 15-day old wererandomly allotted to six dietary treatments containing 0 (control), 100, 250, 500, 1000and 3000 mg kg−1propolis, respectively. Each treatment consisted of four replicates of 21birds each. Heat stress at 32◦C was applied daily from 08:00 am to 17:00 pm from day15–42. Twelve birds per treatment were randomly taken and marked with livestock colorfor behavioral observation. Treatment effects on behavioral patterns were recorded usingdirect observation instantaneous scan sampling technique. At the end of the experiment(42 days of age) the three birds used for behavioral observation were feather scored (from 1to 5); while all birds (504) were individually scanned for primary feather abnormalities. Theresults indicated that the effects of using propolis as a feed additive for broilers reducedheat stress behavior, especially dietary treatment with 250 or 3000 mg kg−1propolis, byincreasing bird walking activities and reducing panting behaviors (P 0.05, respectively).Moreover, 250 mg kg−1propolis (P 0.05) increased standing behavior also. Walking activ-ities was also increased in the birds fed with 100 mg kg−1propolis (P 0.05). There were nosignificant (P > 0.05) treatment effects on sitting, preening, feeding, drinking, wing eleva-tions and feather pecking activities. Propolis at current doses did not significantly (P > 0.05)improve feather scoring, but reduced (P = 0.048) abnormal shape of primary feathers. Thecurrent results support that propolis treatment may be considered as a protective manage-ment practice in broiler chickens to alleviate the negative effects of heat stress, but furtherinvestigations may requested to determine the best type, dose, time and duration of itsadministration.

This experiment was conducted to evaluate the effects of dietary supplementation of greenBrazilian propolis on behavioral patterns and feather condition of heat stressed broilerchickens. Five hundred and four (504) male Ross 708 broiler chicks at 15-day old wererandomly allotted to six dietary treatments containing 0 (control), 100, 250, 500, 1000and 3000 mg kg−1propolis, respectively. Each treatment consisted of four replicates of 21birds each. Heat stress at 32◦C was applied daily from 08:00 am to 17:00 pm from day15–42. Twelve birds per treatment were randomly taken and marked with livestock colorfor behavioral observation. Treatment effects on behavioral patterns were recorded usingdirect observation instantaneous scan sampling technique. At the end of the experiment(42 days of age) the three birds used for behavioral observation were feather scored (from 1to 5); while all birds (504) were individually scanned for primary feather abnormalities. Theresults indicated that the effects of using propolis as a feed additive for broilers reducedheat stress behavior, especially dietary treatment with 250 or 3000 mg kg−1propolis, byincreasing bird walking activities and reducing panting behaviors (P 0.05, respectively).Moreover, 250 mg kg−1propolis (P 0.05) increased standing behavior also. Walking activ-ities was also increased in the birds fed with 100 mg kg−1propolis (P 0.05). There were nosignificant (P > 0.05) treatment effects on sitting, preening, feeding, drinking, wing eleva-tions and feather pecking activities. Propolis at current doses did not significantly (P > 0.05)improve feather scoring, but reduced (P = 0.048) abnormal shape of primary feathers. Thecurrent results support that propolis treatment may be considered as a protective manage-ment practice in broiler chickens to alleviate the negative effects of heat stress, but furtherinvestigations may requested to determine the best type, dose, time and duration of itsadministration.

This experiment was conducted to evaluate the effects of dietary supplementation of greenBrazilian propolis on behavioral patterns and feather condition of heat stressed broilerchickens. Five hundred and four (504) male Ross 708 broiler chicks at 15-day old wererandomly allotted to six dietary treatments containing 0 (control), 100, 250, 500, 1000and 3000 mg kg−1propolis, respectively. Each treatment consisted of four replicates of 21birds each. Heat stress at 32◦C was applied daily from 08:00 am to 17:00 pm from day15–42. Twelve birds per treatment were randomly taken and marked with livestock colorfor behavioral observation. Treatment effects on behavioral patterns were recorded usingdirect observation instantaneous scan sampling technique. At the end of the experiment(42 days of age) the three birds used for behavioral observation were feather scored (from 1to 5); while all birds (504) were individually scanned for primary feather abnormalities. Theresults indicated that the effects of using propolis as a feed additive for broilers reducedheat stress behavior, especially dietary treatment with 250 or 3000 mg kg−1propolis, byincreasing bird walking activities and reducing panting behaviors (P 0.05, respectively).Moreover, 250 mg kg−1propolis (P 0.05) increased standing behavior also. Walking activ-ities was also increased in the birds fed with 100 mg kg−1propolis (P 0.05). There were nosignificant (P > 0.05) treatment effects on sitting, preening, feeding, drinking, wing eleva-tions and feather pecking activities. Propolis at current doses did not significantly (P > 0.05)improve feather scoring, but reduced (P = 0.048) abnormal shape of primary feathers. Thecurrent results support that propolis treatment may be considered as a protective manage-ment practice in broiler chickens to alleviate the negative effects of heat stress, but furtherinvestigations may requested to determine the best type, dose, time and duration of itsadministration.

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