Rumination Bouts Research Articles

Daylong acoustic recordings of grazing and rumination activities in dairy cows

Monitoring livestock feeding behavior may help assess animal welfare and nutritional status, and to optimize pasture management. The need for continuous and sustained monitoring requires the use of automatic techniques based on the acquisition and analysis of sensor data. This work describes an open dataset of acoustic recordings of the foraging behavior of dairy cows. The dataset includes 708 h of daily records obtained using unobtrusive and non-invasive instrumentation mounted on five lactating multiparous Holstein cows continuously monitored for six non-consecutive days in pasture and barn. Labeled recordings precisely delimiting grazing and rumination bouts are provided for a total of 392 h and for over 6,200 ingestive and rumination jaw movements. Companion information on the audio recording quality and expert-generated labels is also provided to facilitate data interpretation and analysis. This comprehensive dataset is a useful resource for studies aimed at exploring new tools and solutions for precision livestock farming.

Intake, performance, and feeding behavior of Holstein and Holstein × Gyr heifers grazing intensively managed tropical grasses during the rainy season

Holstein × Gyr and Holstein are the primary dairy breeds used in tropical systems, but when rearing under pasture, feed intake, behavior, and performance might differ between them. This study aimed to evaluate the voluntary intake, nutrient digestibility, performance, and ingestive behavior of Holstein and Holstein × Gyr (½ Holstein × ½ Gyr) heifers managed in a rotational system of Guinea grass (Panicum maximum Jacq. cv. Mombaça). The experiment was conducted during the summer season throughout four periods of 21 d. Two 8-heifers (four Holstein and four Holstein × Gyr) groups, averaging 258.6 ± 24.79 kg and 157.1 ± 24.99 kg BW, were used. Each group grazed a separate set of 16 paddocks, and all heifers received a concentrate supplement daily. Heifers were weighed at the beginning and end of the experiment. Fecal, forage and concentrate samples were evaluated for their DM, CP, crude fat, ash, NDF, and indigestible NDF. Feeding behavior was evaluated through 24 h of live observation for 48 h of each experimental period. Grazing, ruminating, resting, and intake of concentrate times were recorded, and rumination criteria, bout criteria, mealtime, meal frequency, and meal duration were calculated. There was no difference in total dry matter intake (DMI), but forage DMI of Holstein × Gyr was 11.70 % greater than the Holstein heifers. The Holstein × Gyr heifers had greater NDF intake and feed efficiency tended to show greater CP and NDF digestibilities, consequently, they had greater average daily gain (ADG). Holstein grazed less than Holstein × Gyr heifers in the afternoon. Ruminating time was 18.43 % lower for Holstein than Holstein × Gyr heifers, and rumination criteria (i.e. longest non-feeding interval within a rumination event) were greater for Holstein heifers. Holstein heifers presented more prolonged rumination bouts and resting time than Holstein × Gyr heifers. Holstein × Gyr can ingest and ruminate greater amounts of fibrous material, and Holstein heifers needed to spend more time ruminating the cud. Overall, even though the behavior was not markedly different between breeds, rearing young Holstein heifers in tropical pasture conditions is less suitable than Holstein-Gyr because of their lower ADG. Therefore, this management condition seems appropriate for Holstein × Gyr but inappropriate for Holstein dairy heifers.

Feeding behavior of post-weaned crossbred steers supplemented in the dry season of the year.

The objective of this study was to evaluate the feeding behavior of grazing steers supplemented in the dry season of the year. Thirty-two castrated crossbred (½ Holstein-Zebu) steers with an average initial weight of 378 ± 7.54kg, aged 14months, were distributed into four treatment groups in a completely randomized design with eight replicates. The animals were managed in an area covered with a pasture of Brachiaria brizantha cv. Marandu, in a rotational grazing system. The supplement was formulated so that the animals in the different treatment groups would ingest the same amount of crude protein (CP) daily. Thus, the treatments consisted of increasing levels of supplementation, based on the animals' body weight (BW), as the protein content of the supplement was reduced. The following treatments (dry matter basis) were tested: T2, supplement at 0.2% BW, with 50% CP; T4, supplement at 0.4% BW, with 25% CP; T6, supplement at 0.6% BW, with 16.67% CP; and T8, supplement at 0.8% BW, with 12.5% CP. Forage dry matter intake decreased linearly (P < 0.05), characterizing a substitution effect. The increasing supplementation levels influenced the animals' feeding behavior, especially grazing time, total feeding time, number of grazing bouts, and number of bites per day, which showed a positive quadratic response (P < 0.05), and rumination time, number of rumination bouts, number of cuds ruminated per day, and number of chews per ruminated cud, which exhibited a negative quadratic behavior (P < 0.05). Dry matter and neutral detergent fiber (NDF) feed efficiencies and dry matter and NDF rumination efficiencies responded quadratically (P < 0.05). In conclusion, concentrate supplementation at up to 0.8% BW improves the feeding behavior of grazing steers in terms of the intake of concentrate supplement and forage as well as the feed and rumination efficiencies.

Effect of dietary protein level and corn processing on behavior activity of high producing dairy cows

The objective of this experiment was to evaluate the effects of corn processing and protein level on the feeding, lying, and post milking standing (PMS) behavior in high producing cows. Eight Holstein cows were randomly assigned to diets containing either finely ground (FGC) or steam flaked (SFC) corn based on either low (LP) or high (HP) protein content. Cows receiving LP had lower milk yield than cows receiving HP with similar DMI. Moreover, FGC-fed cows had higher DMI than SFC-fed cows with similar milk yields. Eating and rumination time tended to be lower and chewing time was lower in HP-fed cows than LP-fed cows. Cows fed SFC tended to have higher laying rumination interval and lower lying rumination bouts than cows fed FGC. Total and average PMS were lower in cows fed HP than LP. Cows fed LP had higher chewing activity in the daytime than cows fed HP. Our results suggested that the protein level and corn processing affect the standing and lying behavior of high producing dairy cows, although, this effect is marginal. Results also indicated that probably any change in the diet that increases the rumination and eating times could also improve the PMSThe objective of this experiment was to evaluate the effects of corn processing and protein level on the feeding, lying, and post milking standing (PMS) behavior in high producing cows. Eight Holstein cows were randomly assigned to diets containing either finely ground (FGC) or steam flaked (SFC) corn based on either low (LP) or high (HP) protein content. Cows receiving LP had lower milk yield than cows receiving HP with similar DMI. Moreover, FGC-fed cows had higher DMI than SFC-fed cows with similar milk yields. Eating and rumination time tended to be lower and chewing time was lower in HP-fed cows than LP-fed cows. Cows fed SFC tended to have higher laying rumination interval and lower lying rumination bouts than cows fed FGC. Total and average PMS were lower in cows fed HP than LP. Cows fed LP had higher chewing activity in the daytime than cows fed HP. Our results suggested that the protein level and corn processing affect the standing and lying behavior of high producing dairy cows, although, this effect is marginal. Results also indicated that probably any change in the diet that increases the rumination and eating times could also improve the PMS

Effect of Floor Enrichment with Rubber Mattress of Calving Pen on Prepartum Behaviour of Tharparkar Cow during Winter Season

Background: The study was conducted to evaluate the effect of floor enrichment with rubber mattress of calving pen on prepartum calving behaviour of Tharparkar cow during the winter season. Methods: A total 28 Tharparkar cows were taken in study during winter season (November to March) and divided into two groups each contain 14 animals. One group placed in floor enriched with rubber mattress and other group kept on bare concrete floor calving pen. Preparturient behaviours like lying time, standing time, lying bout duration, number of lying bouts, rumination time ,rumination bouts, self grooming and frequency of self grooming were evaluated on -12 hr, -7th day, -14th day and -21st day prepartum for period of 12 hr in a day. Repeated Meausures ANOVA was used for the analysis of the data. Result: It was found that lying time, lying bout duration was significantly more in rubber mattress group as compare to concrete floor. However, 12 hr before parturition standing time was significantly high compare to any other observational day within the group. Similarly, rubber mattress had positive effect on rumination time, lying duration and self grooming frequency as compare to bare concrete floor. It was concluded that rubber mattress had beneficial effect in calving pen of Tharparkar cow during winter season due to its softness and insulating property. It provided comfort and warmth to the parturient cows. which was evident by increase in rumination time, more lying duration and reduced self grooming frequency.

Meta-analysis of rumination behavior and its relationship with milk and milk fat production, rumen pH, and total-tract digestibility in lactating dairy cows

Time spent ruminating is affected by diet and affects the rumen environment. The objective of the current study was to conduct a meta-regression to characterize the variation in rumination time and its relationship with milk and milk fat yields and variables mechanistically associated with milk fat synthesis, including rumen pH and total-tract digestibility. The analysis included 130 journal articles published between 1986 and 2018 that reported 479 treatment means from lactating Holsteins cows during established lactation. Milk yield averaged 34.3 kg/d (range 14.2-52.1 kg/d), milk fat averaged 3.47% (range 2.20-4.60%), and rumen pH averaged 6.1 (range 5.3-7.0). Rumination observation systems were categorized into 6 groups, but there was little difference in average rumination time among systems. The total time spent ruminating averaged 444 min/d (range 151-638 d) and occurred in 13.8 bouts/d (range 7.8-17.4 bouts/d) that averaged 32.7 min (range 20.0-48.1 min). Bivariate regressions were modeled to include the random effect of study, and correlations were evaluated through the partial R2 that excluded variation accounted for by the random effect. Rumination time was quadratically increased with increasing milk fat yield (partial R2 = 0.27) and milk fat percent (partial R2 = 0.17). Rumination was also increased with increasing milk yield, dry matter intake, and rumen pH, and was quadratically related to dietary neutral detergent fiber (NDF) and total-tract NDF digestibility (partial R2 = 0.10-0.27). Similar relationships were observed for rumination per unit of dry matter and NDF intake. The best-fit multivariate model predicting total rumination time included milk yield, milk fat yield, and concentration and accounted for 37% of the variation. Total-tract digestibility was available for 217 treatment means; when included in the model, the partial R2 increased to 0.41. Last, principal component analysis was conducted to explore the relationship among variables. The first 2 principal components in the broad analyses explained 36.7% of the 39 variables evaluated, which included rumination bouts and time spent ruminating. In conclusion, rumination time was related to milk fat across a large number of studies, although it explained only a limited amount of the variation in milk fat.

Effects of corn grain endosperm type and conservation method on feed intake, feeding behavior, and productive performance of lactating dairy cows

Our objective was to evaluate the effects of corn grain varying in endosperm type and conserved as high-moisture or dry ground corn on dry matter intake (DMI), feeding behavior, ruminal fermentation, and yields of milk and milk components of cows in early to mid-lactation. Seven ruminally and duodenally cannulated Holstein cows (73 ± 39 d in milk; mean ± SD) were used in a duplicated 4 × 4 Latin square design with 21-d periods. A 2 × 2 factorial arrangement of treatments was used with main effects of corn grain endosperm type (floury or vitreous) conserved as high-moisture corn (HMC) or dry ground corn (DGC). Rations were formulated to contain 27.0% starch, 26.6% neutral detergent fiber (NDF), 19.1% forage NDF, and 16.5% crude protein. Corn grain treatments supplied 86.6% of dietary starch and contained alfalfa silage as the sole forage. Dry matter intake was increased 1.3 kg/d by DGC compared with HMC. The increase in DMI by DGC was related to a shorter intermeal interval (104.4 vs. 118.2 min/d), and meal size was not affected by treatment. Dry ground corn decreased rumination bout length and number of chews per bout compared with HMC. No differences were detected between endosperm treatments for DMI, yields of milk, 3.5% fat-corrected milk (FCM), milk fat, protein, lactose, or solids-not-fat (SNF). Mean yield of 3.5% FCM across treatments was 47.5 kg/d. However, a tendency for an interaction was observed for feed efficiency; floury endosperm increased efficiency 0.05 kg 3.5% FCM per kg of DMI for DGC but decreased it by 0.14 kg 3.5% FCM per kg of DMI for HMC relative to vitreous endosperm. Vitreous compared with floury corn tended to increase true protein concentration in milk when conserved as DGC (2.68% vs. 2.62%) but not as HMC. Concentration of SNF was increased by DGC compared with HMC (8.45 vs. 8.37%) due, in part, to the effect of treatment on milk protein concentration. Body weight was not affected by treatment, but vitreous endosperm tended to increase loss of body condition compared with floury endosperm. Corn endosperm type and conservation method had little effect on productive performance of high-producing cows.

Associations between body condition score, locomotion score, and sensor-based time budgets of dairy cattle during the dry period and early lactation

Lameness, one of the most important disorders in the dairy industry, is related to postpartum diseases and has an effect on dairy cow welfare, leading to changes in cows' daily behavioral variables. This study quantified the effect of lameness on the daily time budget of dairy cows in the transition period. In total, 784 multiparous dairy cows from 8 commercial Dutch dairy farms were visually scored on their locomotion (score of 1-5) and body condition (score of 1-5). Each cow was scored in the early and late dry period as well as in wk 4 and 8 postpartum. Cows with locomotion scores 1 and 2 were grouped together as nonlame, cows with score 3 were considered moderately lame, and cows with scores 4 and 5 were grouped together as severely lame. Cows were equipped with 2 types of sensors that measured behavioral parameters. The leg sensor provided number of steps, number of stand-ups (moving from lying to standing), lying time, number of lying bouts, and lying bout length. The neck sensor provided eating time, number of eating bouts, eating bout length, rumination time, number of rumination bouts, and rumination bout length. Sensor data for each behavioral parameter were averaged between 2 d before and 2 d after locomotion scoring. The percentage of nonlame cows decreased from 63% in the early dry period to 46% at 8 wk in lactation; this decrease was more severe for cows with higher parity. Cows that calved in autumn had the highest odds for lameness. Body condition score loss of >0.75 point in early lactation was associated with lameness in wk 4 postpartum. Moderately lame cows had a reduction of daily eating time of around 20 min, whereas severely lame cows had a reduction of almost 40 min. Similarly, moderately and severely lame dry cows showed a reduction of 200 steps/d, and severely lame cows in lactation showed a reduction of 600 steps/d. Daily lying time increased by 26 min and lying bout length increased by 8 min in severely lame cows compared with nonlame cows. These results indicate a high prevalence of lameness on Dutch dairy farms, with an increase in higher locomotion scores from the dry period into early lactation. Time budgets for multiparous dairy cows differed between the dry period and the lactating period, with a higher locomotion score (increased lameness) having an effect on cows' complete behavioral profile. Body condition score loss in early lactation was associated with poor locomotion postpartum, whereas lameness resulted in less eating time in the dry period and early lactation, creating a harmful cycle.

An online method for estimating grazing and rumination bouts using acoustic signals in grazing cattle

The growth of the world population expected for the next decade will increase the demand for products derived from cattle (i.e., milk and meat). In this sense, precision livestock farming proposes to optimize livestock production using information and communication technologies for monitoring animals. Although there are several methodologies for monitoring foraging behavior, the acoustic method has shown to be successful in previous studies. However, there is no online acoustic method for the recognition of rumination and grazing bouts that can be implemented in a low-cost device. In this study, an online algorithm called bottom-up foraging activity recognizer (BUFAR) is proposed. The method is based on the recognition of jaw movements from sound, which are then analyzed by groups to recognize rumination and grazing bouts. Two variants of the activity recognizer were explored, which were based on a multilayer perceptron (BUFAR-MLP) and a decision tree (BUFAR-DT). These variants were evaluated and compared under the same conditions with a known method for offline analysis. Compared to the former method, the proposed method showed superior results in the estimation of grazing and rumination bouts. The MLP-variant showed the best results, reaching F1-scores higher than 0.75 for both activities. In addition, the MLP-variant outperformed a commercial rumination time estimation system. A great advantage of BUFAR is the low computational cost, which is about 50 times lower than that corresponding to the former method. The good performance and low computational cost makes BUFAR a highly feasible method for real-time execution in a low-cost embedded monitoring system. The advantages provided by this system will allow the development of a portable device for online monitoring of the foraging behavior of ruminants.Web demo available at: https://sinc.unl.edu.ar/web-demo/bufar/.

Effects of feeding live yeast at 2 dosages on performance and feeding behavior of dairy cows under heat stress

The objectives were to evaluate the effects of feeding different amounts of supplemental live yeast (LY) on performance and digestion of cows under heat stress. Sixty Holstein cows, 27 multiparous and 33 primiparous, were blocked by parity and milk yield in the first 20 d in milk (DIM) and randomly assigned to receive 0, 0.5, or 1.0 g/d of LY, resulting in daily intakes of 0, 14.2, and 37.6 billion cells, respectively, of Saccharomyces cerevisiae strain CNCM I-1077 from 30 to 107 DIM. Cows were milked twice daily, dry matter intake (DMI) and milk yield were measured daily, and milk components, body weight, and body condition were measured weekly. Blood was sampled weekly and plasma analyzed for concentrations of glucose, fatty acids, urea N, haptoglobin, serum amyloid A, and acid-soluble protein. Digestibility of nutrients was measured in the last 2 wk of the experiment. Ruminal fluid was collected on 2 consecutive days 6 h after the morning feeding for measurements of pH, concentrations of short chain fatty acids, and NH3-N. Feeding behavior was observed for 48 h on experiment d 21 and 63. The mean ambient temperature was 26.8°C, humidity was 83.2%, and the temperature and humidity index ranged from 73 to 81. Treatment did not affect rectal temperature (38.9 ± 0.04°C) or DMI but increased yield of energy-corrected milk (ECM; 35.2 vs. 36.1 vs. 37.2 kg/d for 0, 0.5, and 1.0 g/d, respectively) and efficiency of conversion of DM into ECM (1.70, 1.79, and 1.83 for 0, 0.5, and 1 g/d, respectively). Feeding LY increased digestibility of crude protein (65.1 vs. 68.8 vs. 70.4%) and neutral detergent fiber (NDF; 47.5 vs. 49.2 vs. 55.2%), and concentration of acetate (64.7 vs. 69.1 vs. 72.2 mM), which resulted in increased concentration of total short chain fatty acids in ruminal fluid (110.3 vs. 117.7 vs. 121.4 mM). Mean ruminal pH increased (5.99 vs. 6.03 vs. 6.26), and proportion of cows with pH <5.8 decreased linearly (42.9 vs. 34.9 vs. 7.7%) with increasing inclusion of LY. Concentrations of acute-phase proteins decreased with increasing amount of LY. Some aspects of feeding behavior were altered by LY, and meal size reduced quadratically (3.2, 3.5, and 2.9 kg of DM, respectively), whereas interval between rumination bouts tended to reduce linearly (122, 96.5, and 90.7 min, respectively) with increasing dose of LY. Chewing time per kilogram of NDF tended to increase linearly (71.6, 71.3, and 81.6 min/kg, respectively) with increasing dose of LY. The estimated net energy for lactation of the diet increased 5.2%, from 1.72 Mcal/kg of DM for 0 g of LY to 1.81 Mcal/kg for 1 g of LY. Feeding 1 g of LY/d to cows under heat stress increased yield of ECM and efficiency of feed conversion into ECM, improved diet digestibility, and increased ruminal fluid pH; these responses might be related either to direct effects of LY on ruminal microbial activity or to changes in feeding behavior that improved digestion of cows in heat stress.

Reciprocal combinations of alfalfa hay and corn silage in the starter diets of Holstein dairy calves: Effects on feed sorting, meal pattern, and ingestive behavior

We investigated the effects of replacing alfalfa hay (AH) with corn silage (CS) in the starter diet on feed intake, feeding and chewing behavior, and sorting activity using 30 newborn male Holstein calves which were assigned randomly to 3 groups receiving starter diets containing chopped AH [100.00 g/kg on dry matter (DM) basis; AH), CS (100.00 g/kg; CS), or their equal combination (AHCS). The starter diets had the same nutrient composition but differed in DM content (P = 0.001) and thereby, particle size distribution. Feeding AHCS or CS tended to increase day time meal duration (pre-weaning; P = 0.09) and meal frequency (post-weaning; P = 0.08) and tended (P = 0.08) to decrease inter-meal interval (post-weaning), and thereby, tended to increase (P = 0.09) and increased (P = 0.04) day time eating time during the pre- and post-weaning periods, respectively, without affecting nutrient intake or body weight. Calves fed AHCS or CS had lower eating rate during the pre-weaning period (P = 0.03). Concurrent increase in day time rumination frequency (P = 0.04) and duration (P = 0.04) together with a decrease in rumination bout interval (P = 0.03) in calves fed AHCS or CS increased ruminating time (P = 0.001) during the post-weaning period. Time devoted to standing and lying decreased (P = 0.002) and tended (P = 0.06) to decrease, respectively, as the amount of CS increased in the starter diets during the post-weaning period. Calves fed AH or AHCS sorted for the particles retained on second (P = 0.001) and third (P = 0.001) sieves of the Penn State Particle Separator (PSPS) and against the feed materials retained on the bottom pan (P = 0.001); however, calves fed CS sorted against the particles retained on second sieve of the PSPS and for the particles retained on third sieve of the PSPS and feed materials retained on the bottom pan. Crude protein and neutral detergent fiber intakes of particles retained on the both 8.00- and 1.18-mm sieves increased and tended to increase, respectively, in calves fed AHCS or CS compared with calves fed AH. Blood concentration of albumin was higher in calves fed AHCS compared with calves fed AH or CS during the pre-weaning period (P = 0.001). Overall, replacing AH with CS increased day time eating time by increasing meal frequency and duration or decreasing inter-meal interval but did not influence feed intake due to lower eating rate. Finally, calves exhibited feed sorting at the extent to which they balanced intake of nutrients and met their nutritional needs.

Substituting corn silage with reconstituted forage or nonforage fiber sources in the starter feed diets of Holstein calves: Effects on intake, meal pattern, sorting, and health

We examined the effect of replacing corn silage (CS) with reconstituted alfalfa hay (RAH) or reconstituted beet pulp (RBP) in the starter diets on feeding behavior, sorting, and health criteria using 54 neonatal female Holstein calves that were assigned randomly to 3 groups receiving starter diets containing CS (10% on a dry matter basis), RAH, or RBP. The starter diets had the same nutrient composition and moisture level but differed in particle size distribution. Calves fed CS tended to have a lower intermeal interval compared with calves fed RAH before weaning; however, meal frequency and duration, eating rate, and meal size were not affected by treatment before and after weaning, which resulted in no changes in feed intake and time spent eating. Rumination frequency was higher for calves fed CS than for calves fed RAH or RBP after weaning. Feeding RBP decreased rumination duration compared with CS and RAH after weaning; however, calves fed RBP had a higher rumination bout interval compared with calves fed CS. Calves fed CS spent more time ruminating compared with calves fed RAH or RBP after weaning. Feeding CS tended to decrease and decreased time devoted to standing and lying, respectively, compared with calves fed RBP; however, calves fed RBP tended to spend more time on nonnutritive oral behaviors compared with calves fed RAH. Calves fed CS sorted against particles retained on the 8-mm sieve of the Penn State Particle Separator (PSPS) and for particles retained on the 1.18-mm sieve of the PSPS. Feeding RAH increased sorting for particles retained on the 8- and 1.18-mm sieves of the PSPS. Calves fed RBP sorted only for particles retained on the 1.18-mm sieve of the PSPS. Calves fed RBP tended to be more susceptible to developing pneumonia compared with calves fed CS or RAH; however, frequency and duration of diarrhea and pneumonia or number of days needed to medicate the diseases were unchanged across treatment groups. Initial (d 3) blood total protein concentration was similar (6.51 g/dL) across treatment groups. Overall, replacing CS with RAH or RBP did not affect time devoted to eating and feed intake due to no significant changes in meal size or intermeal interval before and after weaning. Calves showed feed sorting at the extent to which they balanced intake of nutrients and met their nutritional needs. Calves in general were healthy; therefore, CS, RAH, or RBP can be used interchangeably based on availability and competitive feed price.

Grain source and chromium supplementation: effects on feed intake, meal and rumination patterns, and growth performance in Holstein dairy calves

Carbohydrate-rich diets may increase urinary excretion of chromium (Cr) and increase its requirements. This study was conducted to investigate the effect of grain type (barley v. corn) and Cr supplementation on feed intake, feeding behavior and weight gain in dairy calves. Forty-eight neonatal Holstein female calves were assigned randomly to four experimental diets in a 2×2 factorial arrangement. Experimental diets were either barley-based diet (BBD) or corn-based diet (CBD) supplemented with (+Cr) or without (−Cr) Cr as Cr-methionine (0.05 mg/kg of BW0.75). Chromium was provided in milk (from days 3 to 73 of life) during the pre-weaning period and then in pre-warmed water (from day 74 until day 94 of life) after weaning. Meal length tended to increase in calves fed the BBD v. CBD during the pre-weaning period. During the post-weaning period, meal size, inter-meal interval, and eating rate increased concurrently but meal frequency and eating time decreased in the BBD v. CBD. During the pre-weaning period, feed efficiency, BW at weaning, and heart girth increased and non-nutritive oral behaviors tended to decrease with Cr supplementation. Due to increased meal frequency, the starter feed intake but not eating time increased by Cr supplementation during the post-weaning period. Supplementing Cr increased starter feed intake, final BW, average daily gain and heart girth during the overall period. Rumination time increased in BBD+Cr calves due to increases in the frequency and duration of rumination, or decreased rumination bout interval. Overall, the type of grain had no effect on feed intake and growth performance; however, Cr supplementation decreased non-nutritive oral behaviors and increased starter feed intake via increasing the meal frequency and thereby improved growth performance.

A regularity-based algorithm for identifying grazing and rumination bouts from acoustic signals in grazing cattle

Continuous monitoring of cattle foraging behavior is a major requirement for precision livestock farming applications. Several strategies have been proposed for this task but monitoring of free-ranging cattle for a long period of time has not been fully achieved yet. In this study, an algorithm is proposed for long-term analysis of foraging behavior that uses the regularity of this behavior to recognize grazing and rumination bouts. Acoustic signals are analyzed offline in two main stages: segmentation and classification. In segmentation, a complete recording is analyzed to detect regular masticatory events and to define the time boundaries of foraging activity blocks. This stage also defines blocks that correspond to no foraging activity (resting bouts). The detection of event regularity is based on the autocorrelation of the sound envelope. For classification, the energy of sound signals within a block is analyzed to detect pauses and to characterize their regularity. Rumination blocks present regular pauses, whereas grazing blocks do not. The evaluation of the proposed algorithm showed very good results for the segmentation task and activity classification. Both tasks were extensively analyzed with a new set of multidimensional metrics. Frame-based F1-score was up to 0.962, 0.891 and 0.935 for segmentation, rumination classification, and grazing classification, respectively. The average time estimation error was below 0.5 min for classification of rumination and grazing on recordings of several hours in length. In addition, a comparison for rumination time estimation was done between the proposed system and a commercial one (Hi-Tag; SCR Engineers Ltd., Netanya, Israel). The proposed algorithm showed a narrower error distribution, with a median of −2.56 min compared to −13.55 min in the commercial system. These results suggest that the proposed system can be used in practical applications.Web demo available at: http://sinc.unl.edu.ar/web-demo/rafar/.

Evaluation of an ear-tag-based accelerometer for monitoring rumination in dairy cows

The objective of this study was to evaluate the ear-tag-based accelerometer system Smartbow (Smartbow GmbH, Weibern, Austria) for detecting rumination time, chewing cycles, and rumination bouts in indoor-housed dairy cows. For this, the parameters were determined by analyses of video recordings as reference and compared with the results of the accelerometer system. Additionally, we tested the intra- and inter-observer reliability as well as the agreement of direct cow observations and video recordings. Ten Simmental dairy cows in early lactation were equipped with 10-Hz accelerometer ear tags and kept in a pen separated from herd mates. A total mixed ration was fed twice a day via a roughage intake control system. During the study, cows' rumination and other activities were directly observed for 20 h by 2 trained observers. Additionally, cows were video recorded for 19 d, 24 h a day. After exclusion of unsuitable videos, 2,490 h of cow individual 1-h video sequences were eligible for further analyses. Out of this, one hundred 1-h video sequences were randomly selected and visually and manually classified by a trained observer using professional video analyses software. Based on these analyses, half of the data was used for development (based on data of 50-h video analyses) and testing (based on data of additional 50-h video analyses) of the Smartbow algorithms, respectively. Inter- and intra-observer reliability as well as the comparison of direct against video observations revealed in high agreements for rumination time and chewing cycles with Pearson correlation coefficients >0.99. The rumination time, chewing cycles, as well as rumination bouts detected by Smartbow were highly associated (r > 0.99) with the analyses of video recordings. Algorithm testing revealed in an underestimation of the average ± standard deviation rumination time per 1-h period by the Smartbow system of 17.0 ± 35.3 s (i.e., -1.2%), compared with visual observations. The average number ± standard deviation of chewing cycles and rumination bouts was overestimated by Smartbow by 59.8 ± 79.6 (i.e., 3.7%) and by 0.5 ± 0.9 (i.e., 1.6%), respectively, compared with the video analyses. In summary, the agreement between the Smartbow system with video analyses was excellent. From a practical and clinical point of view, the detected differences were negligible. However, further research is necessary to test the system under various field conditions and to evaluate the benefit of incorporating rumination data into herd management decisions.

Evaluation of the RumiWatchSystem for measuring grazing behaviour of cows

Feeding behaviour is an important parameter of animal performance, health and welfare, as well as reflecting levels and quality of feed available. Previously, sensors were only used for measuring animal feeding behaviour in indoor housing systems. However, sensors such as the RumiWatchSystem can also monitor such behaviour continuously in pasture-based environments. Therefore, the aim of this study was to validate the RumiWatchSystem to record cow activity and feeding behaviour in a pasture-based system. The RumiWatchSystem was evaluated against visual observation across two different experiments. The time duration per hour at grazing, rumination, walking, standing and lying recorded by the RumiWatchSystem was compared to the visual observation data in Experiment 1. Concordance Correlation Coefficient (CCC) values of CCC=0.96 for grazing, CCC=0.99 for rumination, CCC=1.00 for standing and lying and CCC=0.92 for walking were obtained. The number of grazing and rumination bouts within one hour were also analysed resulting in Cohen‘s Kappa (κ)=0.62 and κ=0.86 for grazing and rumination bouts, respectively. Experiment 2 focused on the validation of grazing bites and rumination chews. The accordance between visual observation and automated measurement by the RumiWatchSystem was high with CCC=0.78 and CCC=0.94 for grazing bites and rumination chews, respectively. These results indicate that the RumiWatchSystem is a reliable sensor technology for observing cow activity and feeding behaviour in a pasture based milk production system, and may be used for research purposes in a grazing environment.

Dietary grain source and oil supplement: Feeding behavior and lactational performance of Holstein cows

Effects of grain source and dietary oil supplement on dry matter intake (DMI), feeding, chewing behavior, and production performance of lactating dairy cows were evaluated using eight multiparous Holstein cows (77±22.1 days in milk; mean±SD) in a duplicated 4×4 Latin square design with a 2×2 factorial arrangement of treatments. Experimental diets contained either ground barley or ground corn supplemented with either fish oil or soybean oil at 2% of dietary dry matter (DM). Geometric mean particle size of dietary treatments was 4.1mm. Dry matter intake tended (P=0.09) to be greater for barley- vs. corn-based diets (23.2 vs. 22.3kg/d), but was reduced for the fish oil compared to soybean oil supplemented diets (21.1 vs. 24.3kg/d; P<0.001). This reduction in DMI was attributed to smaller meal size (1.24 vs. 1.55kg of DM; P=0.004) and slower eating rate (0.082 vs. 0.098kg of DM/min; P<0.001) for fish oil compared to soybean oil supplemented diets. Main treatment effects interacted (P=0.005) for DMI of particles retained on 19mm sieve but not for sorting index. Eating rate (0.090kg of DM/min) was similar between barley- and corn-based diets, however, rumination time was greater for barley- compared to corn-based diets as result of longer rumination bout duration (32.5 vs. 28.5min/bout; P=0.01). Barley- compared to corn-based diets increased total chewing time by 71min (709 vs. 638min) for cows fed fish oil, but not for cows fed soybean oil. Grain source did not affect milk yield or milk composition. Compared to soybean oil, fish oil negatively affected milk yield (40.4 vs. 43.4kg/d; P=0.01), and thereby, both milk fat (0.91 vs. 1.26kg/d; P<0.001) and protein (1.23 vs. 1.33kg/d; P=0.007) production. However, feed efficiency (milk yield/DMI) was greater in fish oil compared to soybean oil supplemented diets (1.94 vs. 1.80; P=0.003). Results indicated that grain source and oil supplement can interact to affect feeding and chewing behavior, but not lactational performance of lactating cows.

The influence of acidosis and live yeast ( Saccharomyces cerevisiae) supplementation on time-budget and feeding behaviour of dairy goats receiving two diets of differing concentrate proportion

Increasing the percentage of concentrate in the diet can influence feeding behaviour of ruminants. It can also lead to subacute rumen acidosis and the addition of yeast to the rumen ecosystem might influence fermentation and subsequently help the ecosystem deal with the consequences of high concentrate diets. The aim of this study was to analyse simultaneously the influence of bouts of acidosis and yeast supplementation (2 × 5 g/day of dried live yeast, Saccharomyces cerevisiae, 2.2 × 10 10 CFU/g given through the rumen cannula) on feeding behaviour and time-budget of 12 cannulated dairy goats, allocated into two groups, and fed successively two diets containing 20% or 50% concentrate. Increasing the proportion of concentrate in the diet decreased the duration of rumination, especially during the night. Studying the sorting behaviour of the goats showed that yeast-supplemented goats ate a less fibrous diet than the one eaten by control goats. Yeast supplementation increased the duration of eating and DMI of the afternoon main meal but did not influence rumination. Bouts of acidosis influenced most of the tested parameters. They increased time spent eating per gram of DMI and decreased duration of rumination, especially during the night. They also decreased the number of meals per day, daily intake rate, duration of afternoon main meal and number and duration of rumination bouts. The greater effects of bouts of acidosis when compared to the effects of diet and yeast supplementation indicates that experiments dealing with high concentrate diets have to be analysed very carefully accounting for the occurrence of acidosis.

Effect of Dietary Strong Ions on Chewing Activity and Milk Production in Lactating Dairy Cows

The objective of this experiment was to determine effects of strong ions on chewing activity and short-term lactational performance of dairy cows. Forty multiparous Holstein cows were used in a replicated 5×5 Latin square design with a 2×2 factorial arrangement of equimolar treatments for cations (sodium and potassium), anions (chloride and bicarbonate), plus a control diet. Periods were 14 d in length with the last 4 d for data and sample collection. Diets were formulated to 29% neutral detergent figer and 17.5% crude protein. Sodium bicarbonate was included at 1% of dry matter in one treatment diet, and other treatments (sodium chloride, potassium chloride, and potassium bicarbonate) were added to be equimolar to sodium bicarbonate in their respective diets. Chewing activity was recorded every 5min for the last 24h of each period. Dry matter intake was not affected by treatment (mean=27.9 kg/d). Bicarbonate treatments increased yields of milk, milk fat, and fat- and solids-corrected milk compared with chloride treatments, but cation treatments did not affect any measured variable. The 4 ion treatments reduced ruminating time per day when compared with control by decreasing the length of rumination bouts. This effect was not specific to cations or anions suggesting a mechanism related to increased ruminal osmolality.

Effects of Fatty Acid Supplements on Feed Intake, and Feeding and Chewing Behavior of Lactating Dairy Cows

Saturated and unsaturated fatty acid supplements (FS) were evaluated for effects on feed intake, meal patterns, and chewing behavior. Eight ruminally and duodenally cannulated cows were used in a replicated 4×4 Latin square design experiment with 21-d periods. Treatments were control and a linear substitution of 2.5% fatty acids from supplemented saturated FS (SAT; prilled, hydrogenated free fatty acids) for partially unsaturated FS (UNS; calcium soaps of long-chain fatty acids). All rations contained identical forage and concentrate components including 37.2% forage and 13.5% cottonseed. Dry matter intake for SAT was not different from control, whereas increasing unsaturated FS linearly decreased dry matter intake by 3.2kg. Wet weight of ruminal digesta decreased linearly up to 11.3kg (13%) with increasing unsaturated FS. Adding supplementary fatty acids did not change meal number, meal length, or time between meals compared with control, but increasing unsaturated FS decreased meal size 0.22kg (9%) within FS. The SAT treatment increased time spent ruminating by 56 (10%) and 42 (7%) min/d compared with control and UNS, respectively. Increasing saturated FS did not affect frequency of rumination bouts or interval between bouts, but increased rumination bout length by 5.6min. Water intake was not affected by treatment, but increasing saturated FS linearly decreased the number of drinking bouts per day by up to 2.9 bouts (23%). Increased unsaturated fatty acid flow to the duodenum decreased feed intake by decreasing meal size, and increased saturated fatty acid flow to the duodenum increased rumination time per day by increasing rumination bout length.