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Distance is a key constraint for animals in moving between suitable habitats, but is this also the case in staging long-distance migrating shorebirds that habitually cover thousands of kilometers during migrations? We conducted multi-year field observations, benthic prey sampling and satellite tracking, to compare how endangered great knots Calidris tenuirostris respond to the food shortage at two similarly functioning staging sites (Gaizhou and Beijingzi) in the northern Yellow Sea, China. Food availability declined by >95 % at both sites across the study period, with the intake rates of great knots declining by 87 %. However, whereas the number of great knots declined by 91 % at Gaizhou, only a 29 % decrease was seen at Beiijngzi. Satellite tracking showed that during the time when food was poor in Gaizhou, tagged great knots crossed 20 km to suitable alternative high-quality sites where food was not scarce. From Beijingzi, tagged great knots flew at least 124 km to find a good alternative. We show that longer distances to alternative sites decreased the probability of a bird leaving. Thus, habitat degradation in staging sites induced great knots to move to alternative sites, but only if such alternatives were relatively close. As staging habitats become more isolated, the negative effects of habitat degradation will be more serious due to a distance constraint on exploratory movements. This emphasizes the importance of maintaining networks of nearby high-quality refueling sites for migratory birds to provide buffers in seasons when local food conditions are lean. [ABSTRACT FROM AUTHOR]

Aflatoxin B1 (AFB1), a naturally occurring mycotoxin (fungal toxin) in maize and nuts, causes liver cancer and has been associated with other adverse health effects. Much less is known about the toxicity of its metabolite AFM1, which is secreted in the milk of mammals. Nonetheless, many nations have set regulatory limits for maximum allowable AFM1 in milk and other dairy products. We collected comprehensive data on the occurrence of AFM1 in samples of milk worldwide, encompassing a wide range of different milk types: raw, pasteurized, ultra-high-temperature treated, fresh, and powdered. For each nation, we found average daily milk intake based on national or global dietary surveys. We then used the AFM1 concentration data and intake rates to calculate AFM1 exposure for adults in multiple nations worldwide. Several nations including Pakistan, India, and several sub-Saharan African nations, had AFM1 levels in milk that substantially exceeded United States and European Union regulatory limits for AFM1, indicating potential risk to individuals in those nations with high milk consumption. Because no regulatory agency has set a tolerable daily intake (TDI) for AFM1, we could not compare our exposure estimates to a TDI to determine at-risk populations. But importantly, high AFM1 levels in milk indicate high levels of AFB1 in animal feed. This may imply that the crops used to make that feed such as maize, may have high AFB1 levels, which upon consumption could harm both animal and human health. • Our study estimates occurrence of and human exposure to aflatoxin M1 (AFM1) globally. • Most nations in most years have average AFM1 levels in milk that meet EU standards. • Several South Asian and African nations have occasional high AFM1 levels in milk. • These extremely high AFM1 levels in milk indicate highly contaminated animal feed. [ABSTRACT FROM AUTHOR]

An understanding of the processes involved in grazing behaviour is a prerequisite for the design of efficient grassland management systems. The purpose of managing the grazing process is to identify sward structures that can maximize animal forage daily intake and optimize grazing time. Our aim was to evaluate the effect of different grazing management strategies on foraging behaviour and herbage intake by sheep grazing Italian ryegrass under rotational stocking. The experiment was carried out in 2015 in southern Brazil. The experimental design was a randomized complete block with two grazing management strategies and four replicates. The grazing management treatments were a traditional rotational stocking (RT), with pre- and post-grazing sward heights of 25 and 5 cm, respectively, and a 'Rotatinuous' stocking (RN) with pre- and post-grazing sward heights of 18 and 11 cm, respectively. Male sheep with an average live weight of 32 ± 2.3 kg were used. As intended, the pre- and post-grazing sward heights were according to the treatments. The pre-grazing leaf/stem ratio of the Italian ryegrass pasture did not differ between treatments (P > 0.05) (~2.87), but the post-grazing leaf/stem ratio was greater (P < 0.001) in the RN than in the RT treatment (1.59 and 0.76, respectively). The percentage of the non-grazed area was greater (P < 0.01) in post-grazing for RN compared with RT treatment, with an average of 29.7% and 3.49%, respectively. Herbage nutritive value was greater for the RN than for the RT treatment, with greater CP and lower ADF and NDF contents. The total time spent grazing, ruminating and resting did not differ between treatments (P > 0.05), with averages of 439, 167 and 85 min, respectively. The bite rate, feeding stations per min and steps per min by sheep were greater (P < 0.05) in the RN than in the RT treatment. The grazing time per hour and the bite rate were greater (P < 0.05) in the afternoon than in the morning in both treatments. The daily herbage intake by sheep grazing Italian ryegrass was greater (P < 0.05) in the RN than in the RT treatment (843.7 and 707.8 g organic matter/sheep, respectively). Our study supports the idea that even though the grazing time was not affected by the grazing management strategies when the animal behaviour responses drive management targets, such as in 'Rotatinuous' stocking, the sheep herbage intake is maximized, and the grazing time is optimized. [ABSTRACT FROM AUTHOR]

In ruminants, feeding behaviour variables are parameters involved in feed efficiency that show variation among individuals. This study aimed to evaluate during the first two production cycles in ruminants the repeatability of feed intake pattern, which is an important aspect of feeding behaviour. Thirty-five dairy goats from Alpine or Saanen breeds were housed in individual pens at four periods (end of first gestation, middle of first and second lactations and middle of second gestation which is also the end of first lactation) and fed a total mixed ration (TMR) ad libitum. Individual cumulative dry matter intake (DMI) was automatically measured every 2 min during the last 4 days of each period. Feed intake pattern was characterized by several measures related to the quantity of feed eaten or to the rate of intake during the 15 h following the afternoon feed delivery. Two main methods were used: modelling cumulative DMI evolution by an exponential model or by a segmentation-clustering method. The goat ability to sort against dietary fibre was also evaluated. There was a very good repeatability of the aggregate measures between days within a period for a given goat estimated by the day effect within breed and goat, tested on the residual variance (P > 0.95). The correlations between periods were the highest between the second and either the third or fourth periods. With increasing age, goats sorted more against the fibrous part of the TMR and increased their initial rate of intake. Alpine goats ate more slowly than Saanen goats but ate during a longer duration. Principal component analysis (PCA) was performed on all the aggregate measures of feed intake patterns. The factor score plots generated by the PCA highlighted the opposition between the different measures of feed intake patterns and the sorting behaviour. The projection of the animals on the scoring plots showed a breed effect and that there was a continuum for the feed intake pattern of goats. In conclusion, this study showed that the feed intake pattern was highly repeatable for an animal in a given period and between periods. This means that phenotyping goats in a younger age might be of interest, either to select them on feeding behaviour and choose preferentially the slow eaters or to adapt the quantity offered and restrict feed delivery to the fast eaters in order to increase feed efficiency and welfare by limiting the occurrence of acidosis, for example. [ABSTRACT FROM AUTHOR]

Intake rates by large herbivores are governed by among other things plant traits. We used Masai giraffe ( Giraffa camelopardalis tippelskirchi Matschie) as study animals, testing whether they as very large browsers would follow the Jarman–Bell principle and maximize intake rate while tolerating low forage quality. We worked in Arusha National Park, Tanzania. We investigated how intake rate was determined by bite mass and bite rate, and show that bite mass and bite rate were determined by plant characteristics, governed by inherent plant traits, plant traits acquired from previous years’ browsing, and season. We predicted that; (1) bite mass would be larger in trees without spines than with (2) bite mass would be larger in the wet season than in the dry, (3) bite rate would be higher in spinescent trees than in non-spinescent, (4) bite rate and/or bite mass would increase with previous years’ browsing, (5) bite mass, bite rate or browsing time per tree would be highest for high trees with large, although still available canopies. Visual observations were used to collect data on tree attributes, number of bites taken and time of browsing. Sample size was 132 observed giraffe. We found that bite mass was larger in spineless than in spinescent trees and was larger in the wet season than in the dry. Bite rate, but not bite mass, increased with increasing browsing in previous years and was highest on two to three meter high trees and in spinescent trees. Intake rate followed bite mass more than bite rate and was higher in spineless than in spinescent trees, higher in the wet season than in the dry, and tended to increase with tree height. Giraffe did not prioritize the highest intake rate, but browsed much on Acacias giving a high quality diet but a low intake rate. [ABSTRACT FROM AUTHOR]

The aim of this study was to understand the benefit of diet mixing for Creole goats grazing native forage species in the central Monte desert of Argentina and the drivers of preference in the mixed diet. To achieve this goal, cafeteria-style experiments were conducted with thirty female Creole goats (2 years old; 44 ± 1.4 kg) and forage species that are typically ingested by goats in this region: Two tanniniferous ( Tricomaria usillo , Mimosa ephedroides ) and three non-tanniniferous shrubs ( Prosopis flexuosa , Capparis atamisquea, Atriplex lampa ). In Experiment 1, goats were assigned to three groups ( n = 10); two groups were offered single tannin-containing shrubs as their basal diet ( T. usillo ; SDTU or M. ephedroides , SDME), whereas the third group received a combination of all five forages (Mixed diet of forages, MD). After a fifteen-day adaptation period, half the animals in each group ( n = 5) were dosed with polyethylene glycol (PEG), a polymer that neutralizes the negative effects of tannins, whereas the other half (Control) were not dosed (CG). Daily dry matter intake (DMI), in vivo apparent digestibility of the diet (ADD) and nitrogen (ADN) were determined. For goats fed MD, preference was estimated based on the DMI of each of the forages offered. Jugular blood samples were collected on the first and last days of the experiment to determine concentrations of blood urea nitrogen (BUN) and serum metabolites indicative of liver damage. In experiment 2, intake rates (IR) of the five forage species were estimated. No significant differences in DMI were detected among treatments. However, goats offered a choice of forages (MD) in the CG treatment had greater diet digestibility and lower BUN than animals fed the single shrubs, showing evidence of a nutritional benefit with dietary diversity. Goats changed their foraging preferences in response to PEG supplementation. Animals in the CG treatment preferred M. ephedroides whereas animals in the PEGG treatment preferred A. lampa. There was a positive correlation between forage preference and IR of crude protein ( r = 0.65; P < 0.001) in PEGG goats, and between forage preference and IR of total tannins ( r = 0.77, P < 0.001) in CG goats. When PEG attenuated biological effects of condensed tannins, goats switched their preference from forages that offered the greatest IR of total tannins (i.e., M. ephedroides ) to those that led to the greatest IR of crude protein (i.e., A. lampa ). In summary, a mixed diet led to greater nutritional benefits than single diets, which contribute to explain the diverse array of food items goats typically show when browsing in the central Monte desert of Argentina. Our results also show that CP, tannins and plant structure (which offer variable intake rates) play significant roles in goats’ foraging preferences in this environment. [ABSTRACT FROM AUTHOR]

Outside the breeding season, most shorebirds use either estuarine or non-estuarine intertidal areas as foraging grounds. The sanderling Calidris alba is mostly associated with coastal sandy beaches, a habitat which is currently at risk worldwide due to increasing coastal erosion, but may also use estuarine sites as alternative foraging areas. We aimed to compare the trophic conditions for sanderlings wintering in estuarine and non-estuarine sites within and around the Tejo estuary, Portugal, where these two alternative wintering options are available within a relatively small spatial scale. To achieve this, we analysed sanderling diet, prey availability, foraging behaviour, and time and energy budgets in the different substrates available in estuarine and non-estuarine sites. In terms of biomass, the most important sanderling prey in the estuarine sites were siphons of the bivalve Scrobicularia plana , polychaetes, staphylinids and the gastropod Hydrobia ulvae . In non-estuarine sites the main prey were polychaetes, the bivalve Donax trunculus and chironomid larvae. Both food availability and energetic intake rates were higher on estuarine sites, and sanderlings spent a higher proportion of time foraging on non-estuarine sites. In the estuary, sanderlings foraged in muddy-sand substrate whenever it was available, achieving higher intake rates than in sandy substrates. In the non-estuarine sites they used both sandy and rocky substrates throughout the tidal cycle but had higher intakes rates in sandy substrate. Estuarine sites seem to offer better foraging conditions for wintering sanderlings than non-estuarine sites. However, sanderlings only use muddy-sand and sandy substrates, which represent a small proportion of the intertidal area of the estuary. The extent of these substrates and the current sanderling density in the estuary suggest it is unlikely that the estuary could provide alternative wintering habitat for sanderlings if they face habitat loss and degradation in coastal sites. [ABSTRACT FROM AUTHOR]

Numerous territories of Sub-Saharan Africa are composed of a mosaic of very different landscape units: cropland, forest, and savannah. This spatial, but also temporal heterogeneity leads to complexity in the analysis of cattle intake behaviour. The instantaneous intake rate (IIR) is generally analysed in relation to forage biomass density (Bm), i.e. the functional response. We analysed the relationship between IIR and Bm and effects of other vegetation and animal factors for two herds of N'Dama cattle grazing freely during the dry season in the complex Sare Yoro Bana landscape located in the Kolda region in Southern Senegal. The available forages included crop residues (from rice, millet and maize), grass and hay, fruits and litter. The amount and quality of biomass declined throughout the dry season. The variation in IIR was large and could be attributed to differences in Bm (for 30%) and differed between seasons and vegetation types (also 30% of variation explained). Effects of animal characteristics such as wither height and requirements were significant but small compared to herbage-related factors. In the middle of the dry season (MDS) the IIR was higher than in the early dry season (EDS), probably due to better herbage prehensibility, whereas in the late dry season total herbage stocks were very low and also IIR was lower than in EDS and MDS. Two different relations were observed between IIR and the bite rate. In the EDS higher bite rate resulted in higher IIR, compared to an absence of such effect in later stages of the season indicating a compensation between ingestion rate and bite size. Based on these result, we conclude that the relation between intake rate and biomass density generally follows a type-2 functional response, modelled by a monotonically saturating function, but is strongly affected by many factors related to herbage palatability. Despite the inherent spatio-temporal complexity of the vegetation and the challenges in observations and data collection these relationships can be quantified for cattle grazing in a heterogeneous semi-arid landscape. [ABSTRACT FROM AUTHOR]

Abstract: Reaction distances under various light intensities (0-19 uE/m2/s), angles of attack, swimming speeds, and percentage of overall foraging success were measured. Extensive efforts have been invested in restoring lean lake trout (Salvelinus namaycush) populations in the Laurentian Great Lakes, but successful natural recruitment of lake trout continues to be rare outside of Lake Superior and parts of Lake Huron. There is evidence of high mortality during the first several months after eggs hatch in the spring, but little is known about the foraging mechanisms of this age-0 life stage. We developed a foraging model for age-0 lake trout (S. namaycush) in response to amphipods (Hyalella azteca) and mysids (Mysis diluviana) by simulating underwater environmental conditions in the Great Lakes using a temperature-controlled chamber and spectrally matched lighting. Reaction distances under various light intensities (0–19 uE/m2/s), angles of attack, swimming speeds, and percentage of overall foraging success were measured. Intake rates under different light intensities and prey densities were also measured. Age-0 lake trout were non-responsive in the dark, but were equally responsive under all light levels tested. Age-0 lake trout also demonstrated a longer reaction distance in response to moving prey, particularly mysids, which had an escape response that reduced overall foraging success. We determined that prey intake rate (numeric or biomass) could be modeled most accurately as a function of prey density using a Michaelis–Menton equation and that even under low mysid densities (3 individuals/m2), age-0 lake trout could quickly satisfy their energetic demands in a benthic setting. [Copyright &y& Elsevier]

It is often necessary to estimate the weight that an individual may be capable of gaining depending on its degree of activity. A simple individual-based model was developed for studying the dynamics of weight in terms of daily behavior and ingestion rate. It was based on the balance between the individual's energy intake and the cost of its daily activities. Costs depend on the weight of the individual and the photoperiod, as well as on the time spent on each activity. Different combinations of ingestion rate, individual's weight, photoperiod length, and time assigned to different activities were used for simulating the weight dynamics, taking the species Rhea americana as a study case. Estimations of energetic costs of the activities were obtained from specialized literature. Using different photoperiods and individual behaviors, the model yields field metabolic rate (FMR) values in agreement with those obtained from direct measurements for other omnivorous bird species. [Copyright &y& Elsevier]

Abstract: We tested an energy intake rate maximisation hypothesis to predict preferences. In experiment 1, five groups of INRA401 dry ewes (G1–G5) grazed down conterminal monocultures of Lolium perenne (L)–Festuca arundinacea (F), 0.50:0.50 by area, at a stocking rate of 92ewesha−1. Both plant species were 220-mm high at the beginning of grazing. Time spent grazing either L or F was measured daily from dawn to dusk in groups G1, G2, G4 and G5, composed of six ewes, using automated cameras. In experiment 2, intake-rate from L and F was measured over two periods (P1 and P2) on a group of 8 dry INRA401 ewes (G3), using the short-term double weighing technique. The four ewes that grazed L in P1 grazed F in P2 and vice versa. Sward height at the beginning of grazing was 220-mm high for both plant species in P1, and 195 and 156mm for L and F, respectively, in P2. Time spent grazing either L or F was measured during P2. During the first 5 days of the grazing down, ewes spent on average 71% of their grazing time on L. A marked switch to F occurred on day 6 on average. Thereafter, there was no more preference for either species. At the time of the switch and thereafter, mean sward height and green leaf mass were, respectively, 25–30mm and 50% lower for L than for F, whereas they were similar at the beginning of the depletion. From the switch to F onwards, the decrease in preference for L was mediated via an increase in the time spent grazing F, rather than a decrease in the time spent grazing L. For a given sward height, DM and DOM intake rates (DMIR and DOMIR) were lower from L than from F in both periods. Ratio of DOM intake rate between L and F (DOMIRL/DOMIRF) at the beginning of grazing was 0.74 and 1.08 on average for P1 and P2, respectively. Two days before the switch, it decreased to 0.59 and 0.70 in P1 and P2, respectively. After the switch, it remained at 0.60 and 0.73 on average in P1 and P2, respectively. These results demonstrate that diet selection cannot simply be explained by a strategy that maximises energy intake rate. We observed a marked interindividual variability in preferences. The degree of preference for L was repeatable between years (P <0.05) in all but one ewe. [Copyright &y& Elsevier]

Abstract: Concerns about biodiversity preservation through grazing have revived interest in feeding choices made by herbivores. In this article, we study the dynamics of behavioural intake response in heterogeneous vegetation, where the size and quality of edible plants is highly diverse and varies from day to day as a result of grazing. We conducted two experiments with ewes grazing in paddocks located in shrubby rangelands. A direct in situ observation method was used, with continuous observation of ingestive bites taken by a continuously monitored individual. A bite coding-grid enabled us to distinguish the extreme diversity between bites masses and structure, including the ones resulting from plant depletion. Flock activities were also scan-sampled. Observations were made throughout complete paddocking sequences, which lasted for about two weeks. Grazing seriously depleted the paddocks since 75–95% of the herbaceous species was consumed. No trend was detected either in daily activity patterns or in intake time-budgets. These two variables were well synchronised between the continuously monitored individuals and their respective flocks. No inter-day trend was observed for dry matter daily intakes, which was twice higher than predictions from existing models on sheep intake. Our data enabled us to explore the relationship between the diversity of instantaneous feeding choices and the quantitative daily intake. On the instantaneous scale (20s), we confirmed the functional relationship between bite mass and bite frequency. Little variation was observed in daily averages of ingestive behaviour components. But these averages hide the extremely large range of instantaneous values (from 0.04 to 1.2g DM for bite mass). When vegetation size and structure declined as a result of grazing, the ewes progressively took larger bite masses with equivalent nutritive quality, thus adopting a pattern of consumption that is not consistent with the general assumption that such bites are chosen during the first day, as a result of the behavioural quantity–quality trade-off. This article provides knowledge about which type of diversity in plant parts size, structure and composition offers a small ruminant satisfying behavioural leeway in composing its meals and reaching physical satiety. We tend to discard pastoral management practices focused on biomass evaluation, and encourage further studies that will help qualify the nature and structure of vegetation that offers adjustment possibilities at both the individual and flock levels. [Copyright &y& Elsevier]

This experiment aimed at studying the behavioral strategies grazing dairy cows use to satisfy their nutritional needs as the day progresses and the possible role of rumen fill in controlling these behavioral strategies. The day was divided into 3 main periods (0600 to 1200 h, 1200 to 1800 h, and 1800 to 2400 h), where the 3 main grazing bouts (dawn, afternoon, and dusk) of dairy cows usually occur. Four late lactating rumen-cannulated dairy cows were used in a repeated measures design; grazing bout was the within-subjects factor. Cows had access to a 1-ha grass sward under a continuous stocking system. To estimate dry matter intake, bite rate, bite mass (BM), and intake rate at the 3 grazing bouts, cows were rumen-evacuated at 0600, 1200, 1800, and 2330 h, and the jaw recorders were fitted to the cows between these time points. Time spent eating by dairy cows at the dusk grazing bout was much longer than that at the other 2 grazing bouts and composed about 40% of the daily total eating time. Total grazing jaw movement (TGJM) rate was constant during the day at around 75/min. Bite rate, BM, and, hence, intake rate increased, but chewing rate decreased as the day progressed. The increase in BM was mainly due to the increase in dry matter content of the grass at dusk rather than increased bite dimensions. Therefore, it could be concluded that the main behavioral strategies dairy cows use to satisfy their nutritional needs under continuous stocking include manipulating their eating time, biting rate, and chewing rate, with little control over TGJM rate and BM. Dairy cows interrupted the first 2 grazing bouts (dawn and afternoon) long before reaching their maximal rumen capacity, indicating that rumen fill is less likely to play a significant role in signaling the termination of these 2 grazing bouts. However, rumen pool sizes were always maximal at the time when the dusk grazing bout ceased, indicating that rumen fill is more likely to play a significant role... [ABSTRACT FROM AUTHOR]

Red deer cause heavy damage to forest production, hence the need to better understand what determines their dietary choices. Deer are selective herbivores. According to the optimal foraging theory (OFT), they should select foods that maximise their net rate of energy gain. For a given nutritional quality, we predict that plant architecture and height should affect deer feeding preferences through intake rate variations. In the first experiment, 12 tame red deer with shoulder height (SH) ranging from 82 to 105 cm were individually offered fresh bunches of Salix caprea at seven heights regularly spaced from 25 to 205 cm. Animals preferred bunches at 85 and 115 cm height (29 and 32% of feeding time). There was a positive relationship between average consumption height (CH) and animal shoulder height (CH=0.99×SH; r2=0.43; P<0.05) but intake rate did not change with consumption height. In the second experiment, 10 fresh bunches of Quercus pedunculata were offered on three wooden structures, resembling a bushy topped (BT), a normal (N) and a five-shoot (FS) oak sapling. For each structure, average bunch height was set at preferred consumption height. Five tame hinds were observed during individual cafeteria trials (double- then triple-choice). Intake rate was slightly higher for FS than for the other structures (FS=23.7 g DM/min, N=22.3 g DM/min and BT=22.0 g DM/min). Preferences were expressed as the proportion of feeding time during the first min of test. In the double-choice trials, preference was higher for FS relative to BT (61%–39%), and for N relative to BT (62%–38%), but similar between FS and N (57%–43%). In the triple-choice trials, preference for FS (44%), N (24%) and BT (32%) differed from 33%–33%–33%. In both trials, there was thus a slight preference for FS, i.e. for the structure where all bunches were widely spaced and at the hinds’ preferred height. Foliage height and, to a lesser extent, structure of saplings thus affect the feeding preferences of red deer. These results can contribute to improving management practices to limit deer damages to commercial plantations. [Copyright &y& Elsevier]

The ingestive behaviour of dairy heifers grazing monocultures of either perennial ryegrass or white clover was characterised. Two different types of jaw movements were characterised: bites (i.e. when herbage was gathered in to the mouth and then severed) and chews (i.e. when herbage severed by a bite was processed before swallowing). The heifers had a total jaw movement rate (i.e. bites+chews) between 70–80 min−1. Of these, 80–90% were bites, with bite mass varying between 0.15–0.30 g DM per bite.Heifers grazing grass spent longer eating (536 min per day versus 436 min per day) compared to those on clover. As average instantaneous dry matter intake rates min−1 were identical on grass and clover swards (both 12.9 g DM min−1), this gave rise to greater daily intakes of grass compared with clover (6.93 kg DM per day versus 5.61 kg DM per day). However, clover had a higher digestibility than grass (59.9 DOMD versus 77.2 DOMD, % DOM in DM) and so animals on the two different swards had similar intakes of digestible organic matter (4.17 kg per day versus 4.27 kg per day). This gave rise to similar daily liveweight gains (0.97 kg per day versus 0.99 kg per day) for heifers kept on grass and clover, respectively. The masticatory processing (chewing) of the herbage appeared to be delayed from grazing to ruminating, with the heifers kept on grass spending longer ruminating (526 min per day versus 267 min per day) and tending to have more ruminating chews per kg DM ingested (5906 per day versus 3117 per day) than those on clover.These findings suggest that the heifers were regulating their intake by adopting a foraging strategy aimed at minimising grazing time. [Copyright &y& Elsevier]

• Structuring relationship established between Bite mass, Intake rate and DM intake. • Sward height a key factor of intake rate, alongside sward bulk density. • Cattle and small ruminants exhibit specific behaviours via biting and chewing rates. • Useful relationships highlighted to calibrate precision agriculture automatic devices. Ingestive behaviour determines the nutrient intake and thus feed efficiency and robustness of ruminants through their ability to adapt to diverse available resources. Grazing behavior of ruminant has been intensively researched, but it is still difficult to get a clear picture of the various relationships linking bite mass to daily intake. To address this issue, we led a meta-analysis (103 publications, 278 experiments) to shed light on the quantitative adaptive feeding behaviour responses of cattle (C) and small ruminants (SR) facing variations in sward characteristics, notably sward height (SH, 18. 7 ± 13.9 cm) and herbage bulk density (HBD, 1.73 ± 1.30 kg DM/m³). All responses plotted as a plateau expressing an adaptive limit with extreme SH and HBD values. The minimum plateau for bite rate (BR, 46.9 ± 14.6/min) was around 40/min, while intake rate (IR) values, different for C and SR, i.e. 69.1 ± 38.1 vs. 99.9 ± 45.7 mg DM/kg Body Weight (BW) per min respectively ranged between a minimum plateau of 50 mg DM//kg BW/min and a maximum plateau around 100 mg DM/kg BW/min. Two other pasture management factors affected IR: herbage allowance (10.16 ± 6.0, DM % BW) and daily proportion of time spent grazing (0.30 ± 0.08). Our results confirm the specific key influence of bite mass (BM, 1.80 ± 1.27 mg DM/kg BW) on IR. The regressions were IR = 145 (1-exp (-b BM)), where b was 0.44 for C vs. 0.54 for SR. This meta-analysis also revealed fundamental differences in behaviour between C and SR that no study to date has attempted to compare. SR have to chew more (2.7 ± 1.2 vs. 1.6 ± 0.5 JM/bite) to ingest the same amount of DM per bite (expressed in relation to BW) as C, which allows them to ingest slightly quicker. [ABSTRACT FROM AUTHOR]

• We evaluated the effect of two grazing management strategies on herbage and animal production. • Rotatinuous stocking is a grazing strategy based on animal ingestive behaviour. • This approach prioritizes the optimal sward structure to maximize intake rate. • Rotatinuous stocking results in greater herbage and animal production. • Trade-off between forage and animal production is overcome with rotatinuous stocking. 'Rotatinuous' stocking is a grazing management strategy based on animal behavioural responses to sward structure which is designed to maximize herbage intake per unit of grazing time. It is an alternative to traditional grazing management practices focusing on pasture use efficiency and maximizing herbage accumulation and harvesting. To investigate this approach, Italian ryegrass (Lolium multiflorum) pastures grazed by sheep were evaluated in 2014 and 2015 under two contrasting grazing management strategies. Paddocks were distributed under a complete randomized block design with four replicates. Grazing management strategies were: traditional rotational stocking (RT), with pre- and post-grazing sward heights of 25 and 5 cm, respectively, and 'Rotatinuous' stocking (RN), with pre- and post-grazing sward heights of 18 and 11 cm, respectively. Thirty-two castrated Texel × Polwarth crossbred lambs were randomly allocated to treatments. As a consequence of grazing strategies, the stocking cycles were 12 and 4, with resting periods of 13 and 35 days, respectively, for RN and RT treatments. Herbage production, total herbage harvested, and feed conversion efficiency were 28%, 20%, and 40%, respectively, greater for RN than for RT treatment. Although the stocking rate was lower, the average daily gain per animal and live weigh gain per hectare were 153% and 43%, respectively, greater for the RN treatment. Despite the RN treatment being orientated to maximize herbage intake per unit of grazing time, it results in greater total herbage production and harvesting. We conclude that the 'Rotatinuous' stocking strategy is not necessarily reversed by low herbage harvesting efficiency. This innovation in grazing management conciliates high herbage and animal production at the same time. [ABSTRACT FROM AUTHOR]

• Ants fed sucrose solutions whose viscosity was increased by the addition of tylose. • This increase of only the viscosity raised antś metabolic rate during feeding. • The volume per pump contraction varied with viscosity but not with concentration. • A low concentration and increased viscosity caused a fast decrease in pump frequency. • Ants could rapidly integrate information from different food properties while feeding. It is well known that viscosity reduces the intake rates in nectar-feeding insects, such as nectivorous ants, though it remains unclear whether viscosity imposes a higher energy investment in these insects, and how this affects their feeding motivation. To address this issue, we studied feeding behavior, metabolism, and pharyngeal pump activity in the carpenter ant Camponotus mus during ingestion of ad libitum sucrose solutions. In some solutions tylose was added to modify viscosity without changing its sucrose concentration, in a way that allowed comparing: (1) two solutions with the same viscosity and different sucrose concentration (10 T and 50), and (2) two solutions with different viscosity and the same sucrose concentration (50 and 50 T). The viscosity increase was detrimental to the metabolic rate and energy balance. Ants feeding on a solution with high sucrose concentration and increased viscosity (50 T) spent extra-time until reaching a crop load similar to that reached by ingesting the solution without tylose (50). For all solutions offered, ants started feeding with the same pharyngeal pump frequencies, reflecting a similar motivation. Interesting, when ants fed on a low sucrose concentration and increased viscosity solution (10 T), their pump frequencies dropped rapidly respect to the pure-sucrose solution (50). On the contrary, pump frequencies for 50 and 50 T remained similar until the end of the intake. Since the pump frequency is strongly modulated by the ant motivation, an increase in viscosity with low sucrose content, demotivates the ants rapidly, suggesting a rapid integration of different kinds of information about the food value. Our results helped to understand how nectivorous ants could modulate their foraging decision-making. [ABSTRACT FROM AUTHOR]

• Herbicides reduce forage and intake rate of deer, especially directly post-harvest. • Closed canopy forests provide almost negligible amounts of suitable forage for deer. • Deer often do not meet nutritional needs in a single stand, regardless of herbicides. • Early seral forests foster shade-intolerant plants that are forage for deer. The increasing intensity of forestry practices, especially using herbicides to promote early survival and growth of planted conifers, has the potential to influence the abundance of nutritious, shade-intolerant forbs and shrubs on which black-tailed deer (Odocoileus hemionus columbianus) and other forest ungulates depend. Therefore, we compared summer forage resources and nutrition of female black-tailed deer in stands that received herbicide treatments paired with stands that did not in Douglas-fir/western hemlock forests of western Washington. We investigated how these responses changed as forests aged from early seral to canopy closure (2–20 years post-harvest) in both treatments, and also in unmanaged mid-seral stands (30–90 years old). We measured the biomass and nutritional quality of understory vegetation and the diet composition, diet quality and nutrient intake of tractable black-tailed deer within each paired stand. We found that herbicides did not affect the rate of closure of the overstory canopy, but influenced plant species composition of the understory vegetation and reduced total and non-conifer understory biomass, primarily in the first 9 years before canopy closure. Herbicides also reduced the biomass of two of the six plant functional groups, evergreen shrubs and deciduous shrubs and trees, but did not reduce forb, graminoid, or fern biomass. Herbicides reduced bite size, harvest rate, daily dry matter intake and daily digestible energy (DE) intake of deer, but increased dietary digestible protein (DP) content, and these effects occurred primarily in the first 3 years post-treatment. Biomass of plants suitable for black-tailed deer, and the deers' bite rate, daily feeding time, dietary DE, and daily digestible DP intake did not respond to herbicides. Our yearling and sub-adult, non-lactating deer met requirements for yearling growth and adult maintenance for dietary DE in 78%, and DE intake in 27% of plots, but only met the higher requirements for lactating females in 5% of plots. All plots where daily DE requirements of lactation or growth were met were <10 years old. Deer were equally likely to obtain diets that satisfied requirements in treated and untreated plots, indicating that although herbicide application reduced understory biomass and DE intake, it did not explain whether deer were able to meet requirements. We also found that the biomass of deciduous shrubs and trees, forbs, and suitable forage was ~25 times greater in 4–9 year old stands than closed canopy stands (14–90 years old), indicating the importance of maintaining early seral habitat for sustaining populations of black-tailed deer. [ABSTRACT FROM AUTHOR]

Presents abstracts of research on forages in dairy production. "Grazing Behavior of Late Lactating Dairy Cows Under Continuous Stocking," by H. Z. H. Taweel, B. M. Tas, J. Dijkstra and S. Tamminga; "Modeling Pasture-Based Split-Calving Dairy Systems Using a Whole Farm Model," by P. C. Beukes, B. S. Thorrold, M. E. Wastney, C. C. Palliser, J. A. S. Lancaster, C. F. Folkers, G. L. Levy, M. Neal and M. J. Auldist; "Effects of Feeding Legume Silage With Differing Tannin Levels on Lactating Dairy Cattle," by U. C. Hymes-Fecht, G. A. Broderick, R. E. Muck and J. D. Graber.

Presents abstracts of research on forages in dairy production. "Grazing Behavior of Late Lactating Dairy Cows Under Continuous Stocking," by H. Z. H. Taweel, B. M. Tas, J. Dijkstra and S. Tamminga; "Modeling Pasture-Based Split-Calving Dairy Systems Using a Whole Farm Model," by P. C. Beukes, B. S. Thorrold, M. E. Wastney, C. C. Palliser, J. A. S. Lancaster, C. F. Folkers, G. L. Levy, M. Neal and M. J. Auldist; "Effects of Feeding Legume Silage With Differing Tannin Levels on Lactating Dairy Cattle," by U. C. Hymes-Fecht, G. A. Broderick, R. E. Muck and J. D. Graber.