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This study aimed to clarify the differences in ingestive behavior between goats and sheep at the bite scale. Animals were allowed to graze a feeding station of bahiagrass (Paspalum notatum Flügge) with two sward heights (short and tall) to two levels of bite depletion (20 and 40 bites). Ingestive behavior variables, which represent the rate and mass of bites and chews, intake rate, bite dimensions, and bite placement characteristics, were quantified. The interspecies difference in ingestive behavior became obvious at the short sward. Goats reduced the inter‐bite distance and maintained bite overlapping but took deeper bites than sheep at the short sward, resulting in slightly greater bite mass. These behavioral changes with efficient chewing may be helpful to maintain the intake rate at the short sward. Sheep maintained their inter‐bite distance regardless of the sward height and decreased overlapping bites at the short sward. These behavioral characteristics in sheep in response to sward height may partly compensate for the decrease in the bite mass at the short sward, although it may not always maintain the intake rate. Thus, the present study suggests that goats and sheep implement different bite scale ingestive behaviors, including bite placement, when they eat short swards. [ABSTRACT FROM AUTHOR]

The aim of this study was to reveal the potential impact of botanically diverse pasture on the nutritional, physiological, and immunological status of grazing cattle using multifaceted indices. Ten Japanese black beef cows (325.5 ± 40.6 kg of body weight [BW], 7.9 ± 3.8 years of age) were used in this experiment. Five of them grazed on a 1.8‐ha grassland (botanically diverse pasture: DP) that was composed of sown grassland and grazable forestland (approximately 34 plant species). The other five cows grazed on 1.0 ha of sown grassland with only a few plant species (botanically monotonous pasture: MP, approximately 5 plant species) for 2 months. Blood samples were collected approximately every 2 weeks. In DP cows, the hemoglobin (HGB) concentration, hematocrit (HCT) ratio, and superoxide dismutase (SOD) activity increased linearly after the start of grazing, as did plasma sodium (Na), calcium (Ca), and potassium (K) concentrations. Urea nitrogen (UN) levels were higher in DP than in MP cows throughout the grazing period, whereas in MP cows, the red blood cell (RBC) count, HGB concentration, and HCT ratio decreased quadratically after the start of grazing. The DP cows gained more BW than the MP cows throughout the grazing period. Thus, the increased intake and/or the change in the ingested plant species in DP cows might have promoted the increase in the plasma UN concentration. In summary, the present study showed that grazing in botanically diverse pasture improved the nutritional and physiological status of cows; however, it aggravated the imbalance of protein and energy intake induced by grazing within 2 months. [ABSTRACT FROM AUTHOR]

The objective of the present study was to evaluate the effects of extensive grazingin a sown pasture with forestland on the health of beef cows by measuring multiple indicators. Ten Japanese Black beef cows were used in this experiment. Five of the ten cows were grazed for two months on a 1.8 ha field. The remaining cows were fed under confinement conditions. Behavioral assessments showed that grazing increased sternum lying with rumination of the cows. The grazing cows did not show any abnormal behaviors. There was a tendency for the numbers of red blood cells and lymphocytes to be lower in grazing cows than in confined cows, whereas the number of neutrophils in grazing cows was significantly higher than that in confined cows. In addition, grazing cows had a higher total antioxidant capacity and glutathione peroxidase activity than confined cows. These results suggest that extensive grazing in a sown pasture with forestland increases natural behaviors, decreases circulating red blood cells and lymphocytes and enhances neutrophil circulation, antioxidant enzyme activity, and antioxidant capacity. [ABSTRACT FROM AUTHOR]

This study aimed to reveal the effects of direct exposure to cold weather under grazing in winter (GW) on the health of Japanese Black beef cattle, as assessed using physiological, immunological, and behavioral parameters. Ten Japanese Black beef cattle (328 ± 45 kg, 7.6 ± 3.4 years of age) were used in this experiment. In winter, five of the 10 cattle grazed for 2 months in a 1.8 ha pasture (GW), and the remaining cattle were fed under confined conditions with tethering (control [CT]). The two groups were fed similar feed during the experiment, except for the grazing forage. Blood samples were collected approximately every 2 weeks. The numbers of neutrophils and monocytes and antioxidant enzyme activity were higher in the GW group than in the CT group (p < 0.05). The proportions of CD4‐single‐positive cells were lower in GW cattle than in CT cattle (p = 0.06). This study showed that direct exposure of beef cattle to cold weather under GW enhanced the levels of circulating neutrophils and monocytes and contributed to the kinetic homeostasis of lymphocytes but also activated antioxidant enzymes due to an increase in oxidative stress. [ABSTRACT FROM AUTHOR]

Tall grasses (>1 m tall) are an important forage resource for grazing ruminants. Understanding the ingestive behavior and short-term intake rate of cattle grazing on tall grasses will help facilitate grazing management of tall grass pastures. The aim of this study was to determine the allocation of jaw movements in grazing cattle in relation to tall grasses and to assess whether such allocations of jaw movements are effective for maintaining a short-term intake rate. Four plants were used as test plants: bahiagrass ( Paspalum notatum Flügge; a short grass), Sudangrass ( Sorghum × drummondii ; a typical tall grass) and two growth forms of a dwarf bamboo ( Sasa senanensis ; a semi-woody form of tall grass): a naturally growing form (NGDB, approximately 2 m tall) and a form that is under grazing (DBUG,<0.8 m). Four Japanese Black cows were allowed to graze each plant in random order. The grazing jaw movements and intake rate were measured using an integrated method with a microsward technique and acoustic monitoring. The cows performed the highest number of total bites (simple bites+chew-bites) for bahiagrass, an intermediate number of total bites for Sudangrass and DBUG and the lowest number of total bites for NGDB ( P <0.05). The total number of chews (simple chews+chew-bites) was similar among NGDB, DBUG, and Sudangrass, whereas the total number of chews for bahiagrass was less than that for dwarf bamboos. The number of observed chew-bites exhibited an order similar to that observed for the number of total bites. As a result of each jaw movement, cows ingesting the DBUG moved their jaws more frequently among the plants, and cows ingesting the bahiagrass performed the fewest grazing jaw movements. Bite mass was considerably greater in the cows ingesting NGDB than in the cows ingesting other plants. Conversely, the chew mass for bahiagrass was clearly greater than that for the two taller plants. Cows ingesting Sudangrass processed the least amount of forage with each chew ( P <0.05). The intake rate did not significantly differ among the plants ( P >0.05), except for Sudangrass. Cows ingested Sudangrass at a lower intake rate than observed for the other plants ( P <0.05). The results suggest that cattle were able to control their ingestive jaw movements depending on plant characteristics such as height, the spatial arrangement of the leaves and leaf morphology. However, the lower short-term intake rate for tall grasses implies that there is a limit to the adaptability of grazing jaw movements. [ABSTRACT FROM AUTHOR]

This study investigated the influence of forage selection on the quality of the diet ingested by beef cows grazed on a dwarf bamboo-dominated pasture. For 13 days each in spring, summer and autumn, eight Japanese Black cows were grazed on a 1.8-ha dwarf bamboo ( Pleioblastus argenteostriatus f. glaber)-dominant pasture during the day. The plant species and number of bites of each species ingested by the cows were recorded, and plant samples were hand plucked to imitate the behavior of the cows during the grazing time on the seventh and 13th days of each period. The botanical and chemical compositions of the available pasture were systematically estimated by sampling 28 plots. The cows slightly avoided dwarf bamboo and preferred grasses on the seventh day of each period. On the 13th day, the cows ate any available forage in the pasture. The selected forages were higher in crude protein and in vitro digestibility and had lower insoluble protein, neutral detergent fiber and lignin contents than the forages available in the pasture during a season. The frequency of the botanical groups selected by the cows was different in autumn from that in spring and summer, and a substantial increase in grasses and a decrease in P. argenteostriatus f. glaber among the selected forages were observed. Although the botanical groups selected by the cows were relatively different between the seasons, an increase in the levels of unavailable fractions such as lignin and insoluble protein and a decrease in in vitro digestibility were observed as the seasons progressed. Thus, the cows could not avoid a decrease in their diet quality in autumn. The selection of forage improved the nutrient intake of the beef cows in terms of chemical and digestible components; however, in a dwarf bamboo-dominated pasture, there is a substantial limitation in the effectiveness of forage selection. [ABSTRACT FROM AUTHOR]

Dwarf bamboo is a significant but unique native forage for cattle grazing in Japan. A pasture dominated by Pleioblastus argenteostriatus f. glaber, a type of dwarf bamboo, was used to evaluate nutrient intake, digestibility of forage and nutritional status of grazing cows. Eight Japanese Black cows were grazed on the pasture, and six among the eight grazing cows were used for the experiment. This experiment consisted of three periods: spring (May), summer (July) and autumn (September–October) in 2002 and 2003. The nutrient intake and digestibility of the cows were estimated by the double indicator method with chromic oxide (Cr2O3) as the external indicator and acid detergent insoluble ash (ADIA) in forages as the internal indicator. The crude protein (CP) and neutral detergent fiber (NDF) contents of forage selected by the cows hardly changed during the grazing seasons in both years. Crude ash, acid detergent lignin (ADL), ADIA, and acid detergent insoluble protein (ADIP) contents were the highest in autumn in both years. Nutrient intake of the cows was lower in autumn than in other seasons. Nutrient digestibility of the cows increased slightly from spring to summer and then decreased in autumn. Metabolizable energy (ME) intake satisfied the maintenance requirements of the cows in spring and summer; however, it was only 50%–70% of the maintenance in autumn for both years. Urea nitrogen concentration in plasma was always high, approximately 20 mg dL−1, during grazing periods. Inorganic phosphate (IP) concentration in plasma was lower than critical value (4.5 mg dL−1) in spring and autumn. Therefore, energy and phosphate supplementation are needed for the cows grazed on P. argenteostriatus f. glaber-dominated pasture. [ABSTRACT FROM AUTHOR]

Highlights • Confinement conditions restrained the expression of normal behaviors in cows. • Sudden confinement may decrease Mg concentrations and increase anxiety in cows. • Antioxidant capacity was lower after cows were moved to confinement. • Changes in the feeding environment increased neutrophil and decreased monocyte. • Nutritional imbalance in grazing was solved within two weeks by a change in feed. Abstract Grazing is thought to contribute to animal health and welfare. However, cattle are often moved from grazing to confinement conditions at the end of the grazing season or due to their production stage. The aim of this study was to clarify the physiological, immunological, and behavioral responses that occur in cows when they are moved from grazing to confinement conditions. Ten Japanese black cows were used in this experiment. Five of the cows grazed on a 1.8-ha field composed of sown pasture and forest land, while the remaining cows were fed under confinement conditions with tethering for two months. Two months later, the grazing cows were moved to confinement conditions with tethering and for two weeks. They were exposed to the same conditions as the confined cows. Blood samples were collected from all cows, and complete blood cell count, leukocyte differentiation, biochemical analysis, and oxidative stress marker analysis were conducted. Behavioral observations were also carried out. The concentrations of blood urea nitrogen (BUN) and magnesium (Mg) and the activity of glutathione peroxidase (GPx) were lower (P ≤ 0.05), while the numbers of red blood cells (RBCs) and lymphocytes, the hematocrit (HCT) percentage, and the concentration of hemoglobin (HGB) were higher after cows were moved to confinement conditions (P < 0.05). The number of monocytes was lower (P = 0.08), and the number of neutrophils decreased on day 3 before increasing on day 14 after the cows were moved to confinement conditions (P = 0.1). The results of the present study suggest that moving the cows from grazing conditions to confinement conditions induced temporary stress, resulting in a reduction in plasma Mg concentrations and eliminating the high levels of immune and antioxidant enzyme activities observed in grazing cows within two weeks. However, the change in feeding conditions recovered blood parameters, such as the number of RBCs and lymphocytes, the HCT percentage, and the concentration of HGB, and these changes were accompanied by improvement in protein and energy status in cows. [ABSTRACT FROM AUTHOR]