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ObjectiveAn experiment was conducted to investigate the effects of a specific mixture of essential oils (MEO), containing thyme, clove and cinnamon EO, on rumen microbial fermentation, nutrient apparent digestibility and blood metabolites in fistulated sheep.MethodsSix sheep fitted with ruminal fistulas were used in a repeated measurement design with two 24-d periods to investigate the effect of adding MEO at 0 (control), 0.8, and 1.6 mL/d on apparent nutrient digestibility, rumen fermentation characteristics, rumen microbial population and blood chemical metabolites. Animals were fed with a 50:50 alfalfa hay:concentrate diet.ResultsRuminal pH, total volatile fatty acids (VFA) concentration, molar proportion of individual VFA, acetate: propionate ratio and methane production were not affected with MEO. Relative to the control, Small peptides plus amino acid nitrogen and large peptides nitrogen concentration in rumen fluid were not affected with MEO supplementation; while, rumen fluid ammonia nitrogen concentration at 0 and 6 h after morning feeding in sheep fed with 1.6 mL/d of MEO was lower (p<0.05) compared to the control and 0.8 mL/d of MEO. At 0 h after morning feeding, ammonia nitrogen concentration was higher (p<0.05) in sheep fed 0.8 mL/d of MEO relative to 1.6 mL/d and control diet. Ruminal protozoa and hyper ammonia producing (HAP) bacteria counts were not affected by addition of MEO in the diet. Relative to the control, no changes were observed in the red and white blood cells, hemoglobin, hematocrit, glucose, beta-hydroxybutyric acid, cholesterol, total protein, albumin, blood urea nitrogen and aspartate aminotransferase and alanine aminotransferase concentration. Apparent total tract digestibility of dry matter, crude proten, organic matter, and neutral detergent fiber were not influenced by MEO supplementation.ConclusionThe results of the present study suggested that supplementation of MEO may have limited effects on apparent nutrient digestibility, ruminal fermentation and protozoa and HAP bacteria count, blood cells and metabolites.

This study was conducted to evaluate the effects of processed apple peel waste (APW), alone or in combination with an enzyme, as a natural antioxidant on broiler chickens under heat stress. A total of 360 unsexed, 28-day-old broilers were assigned to 6 dietary treatments with four replicates (15 broilers per pen). The experiment consisted of a 3 × 2 factorial arrangement with three levels of apple peel waste (0, 50 or 100 g/kg of diet) and two levels of enzyme (0 or 500 mg/kg, ZY Multi(®)). Inclusion of 100-g APW/kg of diet decreased broiler weight gain at 42 days of age. Inclusion of 50 and 100-g APW/kg of diet increased gizzard and small intestine weights. Feeding 50 and 100-g APW/kg increased high-density lipoprotein (HDL) cholesterol and decreased low-density lipoprotein (LDL) cholesterol and malondialdehyde in blood serum at 49 days of age. At 49 days of age, apparent ileal protein digestibility was reduced when 50 and 100-g APW/kg were used in the diet. This study showed that feeding APW up to 50 g/kg from 28 to 49 days of age increased HDL cholesterol and decreased LDL cholesterol in serum and had no adverse effect on broiler performance.

The aim of the study was to determine the effects of different heat-processing methods of flaxseed on the in situ effective dry matter degradability (EDMD) and the in situ effective crude protein degradability (ECPD). The treatments included roasting, steep roasting, rolled roasting, rolled steep roasting, microwave irradiation and extrusion. Three rumen-fistulated sheep were used for in situ incubations. Furthermore, the effects of heat-processing methods on post-ruminal in vitro nutrient disappearance and total tract disappearance were measured by a three-step in vitro technique. The seeds were roasted and extruded at 140°C to 145°C. One lot of roasted seeds was gradually cooled for about 1 h (roasting) and another lot was held in temperature isolated barrels for 45 min (steep roasting). Moreover, roasted and steep roasted flaxseed was rolled in a roller mill. The lowest and highest EDMD was observed for unheated and extruded flaxseed, respectively (p < 0.05). The highest ECPD was observed for extruded flaxseed (p < 0.05). Roasting and microwave irradiation reduced ECPD of flaxseed (p < 0.05). In vitro post-ruminal disappearance of crude nutrients including fibre fractions was highest for rolled-roasted and rolled steep-roasted flaxseed (p < 0.05). The lowest and highest total tract disappearance rates of crude nutrients and fibre fractions were estimated for unheated and extruded flaxseed, respectively (p < 0.05). The post-ruminal disappearance of crude nutrients was also increased by roasting, in which rolling enhanced this effect. In conclusion, all investigated heat treatments had significant effects on in situ and in vitro degradability of nutrients. As well, rolling of roasted flaxseed enhanced the respective effects. Therefore, different methods of heat processing can be used to modify the feed value of flaxseed for specific purposes.

The objective of this study was to compare the feeding behaviour of high-yielding dairy cows in relation to parity during early to peak lactation and to determine whether or not there was any relationship between variables describing their feeding behaviour and total feed intake. Information concerning feed intake of each individual dairy cow is especially valuable for the herd management, particularly in early lactation. However, technical requirements for implementation are rarely given. Therefore, relationships between feed intake and time-related feeding behaviour parameters are of special interest. Time-related parameters could be recorded on farm conditions adapted sensor technology. Seventy high-yielding lactating dairy cows in different parities (23 in the 1st lactation, 17 in the 2nd lactation, and 30 in the 3rd-and-more-lactation) with an average of 11 000 kg milk yield per year were fed using automatic feeders from the 2nd to the 15th week of lactation. 222 231 recorded visits were analysed in three equal periods (period 1 = 7-39, period 2 = 40-72, and period 3 = 73-105 days in milk [DIM]) during early to peak lactation. Visits were clustered in meals based on the estimated meal criterion (28.5 min). The present study yielded the following values for meal frequency, number of visits per meal, meal duration, meal size, daily mealtime, daily dry matter intake (DMI), and feeding rate over the course of the study were 7.61 ± 1.7 (mean ± SD) meals/d, 4.02 ± 1.68 visits/meal, 37.07 ± 13.77 min/meal, 2.96 ± 0.92 kg DM/meal, 272.18 ± 82.14 min/d, 21.46 ± 4.29 kg DM/d, and 85.56 ± 28.77 g DM/min, respectively. Younger cows had more meals per day, more number of visits per meal, longer daily mealtime but a smaller meal size, lower daily DMI, and lower feeding rate compared to older cows (P<0.001). Meal duration and meal size were highly related to the number of visits at feeder per meal (R 2 =0.55-0.63; P<0.001, R 2 =0.25-0.39; P<0.001 respectively). In addition, meal size was highly related to meal duration (R 2 =0.59-0.72; P<0.001). Results from this study, which analysed data based on meal criterion, showed a higher correlation between the selected parameters of feeding behaviour and feed intake. The high correlation between meal duration and meal size could be used to estimate feed intake.Keywords: feeding behaviour, feed intake, parity, dairy cow