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Site fidelity—the tendency to reuse familiar spaces—is expected to improve fitness. Familiarity with the local environment is particularly crucial when resource demands or predation risk are high. Consequently, site fidelity often peaks during reproduction when energetic costs are high and offspring are vulnerable. For many species, the environment they experience is not solely a function of geography but also of the social environment. Social fidelity, the selection for familiar social environments, could constitute an independent or parallel strategy to spatial fidelity when considering behaviour at the spatial–social interface. Using global positioning system locations from caribou across Newfoundland, we tested whether females selected calving sites based on proximity to familiar conspecifics, in addition to geographical (spatial) fidelity. These strategies were synergistic, not alternative, and correlated across the population but more variable within individuals. We also tested whether either form of fidelity affected reproductive success. We failed to detect an effect of spatial or social fidelity on reproductive success in this population. Nevertheless, given the association between social and spatial fidelity and the demonstrated fitness consequences of site fidelity in other systems, familiar conspecifics and the potential benefits these social partners provide may be an underappreciated component driving site fidelity. This article is part of the theme issue 'The spatial–social interface: a theoretical and empirical integration'. [ABSTRACT FROM AUTHOR]

The western region of the wide Thwaites Glacier terminus is characterized by a near‐vertical calving front. The grounding line at this western calving front (WCF) rests on a relatively high ridge, behind which exists a reverse‐sloping bed; retreat of the grounding line into this over‐deepening basin could therefore expose deep calving faces that may be subject to ice‐cliff failure. Here, we use the 3D Helsinki Discrete Element Model to identify the factors that control the calving dynamics in this location. We then focus on the ability of mélange to influence these dynamics given the wide embayment in which Thwaites Glacier terminates. We find that calving along the WCF is currently influenced by ice flow across the grounding line and consequent longitudinal tensile stress and rift formation. Calving is slowed in simulations that are initiated with a highly constricted mélange, with a thicker mélange suppressing calving entirely. We liken the constrained simulations to a scenario in which mélange piles behind a large grounded iceberg. In a future which may see calving become a more dominant control on the retreat of Thwaites Glacier, this type of blockage will be necessary for robust force chains to develop and transmit resistive forces to the terminus. The ability of the mélange to hinder calving at this location will be determined by the presence and rigidity of binding land‐fast sea ice and iceberg keel depths. Therefore, it is necessary to represent calving, mélange and sea ice in a single framework to predict the fate of Thwaites Glacier. Plain Language Summary: Thwaites Glacier, a major outlet glacier of the West Antarctic Ice Sheet, may be vulnerable to rapid retreat. The terminus of Thwaites Glacier is over 100 km wide; in this paper, we focus on the western terminus region, which meets the Amundsen Sea at a near‐vertical ice face. We use a 3D glacier model that simulates ice fracture to identify the factors controlling iceberg calving. We also run simulations to explore the potential for mélange, a conglomerate of variably sized ice pieces in front of a glacier, to impact calving dynamics at this location. Our simulations show that iceberg calving currently occurs through the growth of short ice‐shelf extensions and the loss of resisting forces as the ice begins to float. Our simulations also demonstrate that calving is slowed when a thick immobile mélange is present. The ability of the mélange to apply a backforce to glaciers has been previously identified as an important brake on such calving‐driven retreat. In a future that may see calving become a more dominant control on the retreat of Thwaites Glacier, this type of blockage will be necessary for the transmission of resistive forces to the terminus. Key Points: Calving at Thwaites Glacier's western terminus is controlled by longitudinal tensile stresses and fracturing as basal traction is lost3D modeling demonstrates that mélange, if constrained, can inhibit calving at this locationFuture sea‐ice conditions and iceberg morphology will determine if mélange can compact and transmit substantial resistive forces [ABSTRACT FROM AUTHOR]

In dairy farming, the uncertainty of cow calving date often imposes waiting costs for days on farmers. Improving the accuracy of calving date prediction would mitigate these costs, specifically before a few days of the event. We monitored and analyzed the heart rate patterns of eight pregnant cows in the days leading up to calving using a dedicated monitoring device. We decomposed the heart rate data into three distinct components: trend, daily cycle, and the remainder, and discovered that the heart rate trend exhibited a sharp decline more than 40 h before the calving event via the trend turning point. To detect the turning point, we applied common financial technical indicators traditionally used to identify turning points of asset prices in trading markets for the extracted heart rate trend. This study remains a feasibility study because of the limited observations, but it indicates that these indicators can effectively capture the trend’s turning point in real time, offering a promising approach for enhanced calving prediction. In addition to discussing the practical implications for cow management, we also contemplate the broader utility of these technical indicators in the context of various dynamic scientific data analyses. [ABSTRACT FROM AUTHOR]

Terminus change is a complex outcome of ice‐ocean boundary processes and poses challenges for ice sheet models due to inadequate calving laws, creating uncertainty in sea level change projections. To address this, we quantify glacier termini sinuosity and convexity, testing the hypothesis that terminus morphology reflects dominant calving processes. Using 10 glaciers with diverse calving styles in Greenland over the period from 1985 to 2021, we establish a supervised classification of calving style by comparing morphology and literature‐derived calving observations. Validation with four of these glaciers and flotation conditions and subglacial discharge routing observations confirms concave, smooth termini indicate buoyant flexure dominated‐calving, while convex, sinuous termini suggest serac failure dominated‐calving. We also identify a mixed style where both calving types may occur. We use these classes to label calving style from 1985 to 2021 for all 10 glaciers and explore how this changes over time as glaciers retreat. Plain Language Summary: The ice‐ocean boundary (terminus) of the Greenland ice sheet changes over space and time due to the melt and calving of ice. There is a range of calving behaviors due to many environmental and geometric factors, including changing ocean temperatures, glacier melting, and the geometry of the glacier. This makes representing how these boundary changes in ice sheet models are difficult, leading to uncertainties in predicting sea level rise from retreating glaciers. The study focuses on the shape (morphology) of 10 glaciers from 1985 to 2021, finding that smooth, concave termini indicate a type of calving related to the flotation of the glacier, while sinuous, convex termini indicate melt‐dominated calving. The research helps classify calving styles and understand how they change over time as glaciers retreat. Key Points: Two calving styles are linked to distinct terminus morphologies but both can exist for a single glacier (over time or space)Mixed styles of calving are more difficult to classifyClassifying terminus morphology over time can aid in identifying how terminus calving mechanisms change over time [ABSTRACT FROM AUTHOR]

The scientific research conducted worldwide on the use of probiotics in animal husbandry demonstrates only a positive effect on the functioning of the macroorganism, but questions persist about the various pharmacological effects of multicomponent microbial preparations in combination with enzymes important in the digestion of certain types of productive animals, which makes it important for veterinary medicine and farmers to obtain environmentally friendly and high-quality products. The purpose of this study was to investigate the effect of a multicomponent enzyme and probiotic supplement on the duration of calving stages, prevention of postpartum complications in cows and some haematological parameters. Clinical, haematological, and statistical research methods were employed in this study. The research was conducted in a private dairy farm with 195 cows. The housing conditions and diet of the animals in the control group (n=6) and the experimental group (n = 17) were analogous, and the enzyme and probiotic supplement "ProActivo" (containing enzymes, Bacillus subtilis strain AX20, B. licheniformis strain EA22, and Enterococcus faecium) was added to the diet of the experimental cows at the rate of 10-14 g/animal, once a day, for 21-30 days before calving. A positive effect on the body of pregnant cows was found - elimination of diarrhoea symptoms in 4 days in 100% of diseased animals, and no changes in the control group. The study proved that the prenatal course of probiotic therapy of cows provided 95% prevention of afterbirth retention, a significant (P ≤ 0.001) reduction in the duration of the stage of afterbirth separation in cows of the experimental group (253.9 ± 3.6 min) compared to the control group (326.8 ± 8.9 min). A significant (P ≤ 0.01) increase in the count of lymphocytes by 3.25 ± 0.2 G/l, monocytes by 0.43 ± 0.03 G/l, neutrophils (P ≤ 0.001) by 1.6 ± 0.28 G/l in cows treated with an enzyme-protein supplement was recorded, which is associated with the optimisation of the functioning of the primary immune system and the pharmacosynergistic effect of the multicomponent supplement. The findings obtained are valuable for veterinarians and dairy herd keepers, as the addition of an enzyme and probiotic supplement to the diet of dry cows will facilitate the calving stages and prevent afterbirth retention. [ABSTRACT FROM AUTHOR]

Herein, fast fracture initiation in glacier ice is modeled using a Material Point Method and a simplified constitutive law describing tensile strain softening. Relying on a simple configuration where ice flows over a vertical step, crevasse patterns emerge and are consistent with previous observations reported in the literature. The model's few parameters allows identification of a single dimensionless number controlling fracture spacing and depth. This scaling law delineates two regimes. In the first one, ice thickness does not play a role and only ice tensile strength controls the spacing, giving rise to numerous surface crevasses, as observed in crevasse fields. In this regime, scaling can recover classical values for ice tensile strength from macroscopic field observations. The second regime, governed by ice bending, produces large‐scale, deep fractures resembling serac falls or calving events. Plain Language Summary: In ice sheets and alpine glaciers, fast‐flowing sections are often characterized by crevasse fields that play a significant role in the cryo‐hydrologic system by facilitating meltwater flow, enhancing basal sliding, weakening the ice, and impacting glacier thermodynamics. Modeling these fractures at the glacier scale remains challenging and often necessitates integrating diverse models which hinders the straightforward consideration of physical issues associated with crevasse fields on a large scale. Here, a new numerical framework allows us to conduct field‐scale experiments and paves the way for a scaling law to elucidate the macroscopic factors influencing fracture fields and to easily incorporate crevasse depth and spacing into large‐scale models. A newly discovered scaling law highlights the transition between a mechanical behavior where the regular crevasse spacing is unaffected by geometry to a regime where geometry plays a significant role, particularly in large‐scale fracture processes like glacier calving. While the numerical experiments in this paper focus on glaciers, the model and conceptual framework is versatile and can address the mechanical behavior of fractures in broader geophysical contexts such as snow, rock or ice avalanches, tectonics and landslides. Key Points: Fractures in glacier flow are modeled using material point method with elastoplasticity and tensile strain softeningA dimensional analysis reveals a key dimensionless number characterizing two different regimes of fast fractureOne regime predicts acknowledged ice tensile strength from field observations and characterizes the regular crevasse spacing [ABSTRACT FROM AUTHOR]

The largest uncertainty in future sea-level rise is loss of ice from the Greenland and Antarctic Ice Sheets. Ice shelves, freely floating platforms of ice that fringe the ice sheets, play a crucial role in restraining discharge of grounded ice into the ocean through buttressing. However, since the 1990s, several ice shelves have thinned, retreated, and collapsed. If this pattern continues, it could expose thick cliffs that become structurally unstable and collapse in a process called marine ice cliff instability (MICI). However, the feedbacks between calving, retreat, and other forcings are not well understood. Here we review observed modes of calving from ice shelves and marine-terminating glaciers, and their relation to environmental forces. We show that the primary driver of calving is long-term internal glaciological stress, but as ice shelves thin they may become more vulnerable to environmental forcing. This vulnerability—and the potential for MICI—comes from a combination of the distribution of preexisting flaws within the ice and regions where the stress is large enough to initiate fracture. Although significant progress has been made modeling these processes, theories must now be tested against a wide range of environmental and glaciological conditions in both modern and paleo conditions. Ice shelves, floating platforms of ice fed by ice sheets, shed mass in a near-instantaneous fashion through iceberg calving. Most ice shelves exhibit a stable cycle of calving front advance and retreat that is insensitive to small changes in environmental conditions. Some ice shelves have retreated or collapsed completely, and in the future this could expose thick cliffs that could become structurally unstable called ice cliff instability. The potential for ice shelf and ice cliff instability is controlled by the presence and evolution of flaws or fractures within the ice. [ABSTRACT FROM AUTHOR]

Professor Gerhard Sand (1861–1921) was the first professor of veterinary obstetrics at the Royal Veterinary and Agricultural University, Copenhagen, Denmark. He began teaching the theory and practice of obstetrics to veterinary students in 1887 and spent the following years until his death in 1921 developing the veterinary obstetrics teaching program. During this period, veterinary obstetrics was established as an independent discipline at the Royal Veterinary and Agricultural University. Professor Sand's teaching had a major impact on the field of veterinary obstetrics in Scandinavia. He was devoted to teaching veterinary obstetrics and produced a number of obstetrical illustrations, some of which showed different causes of dystocia, mainly fetal malpresentation in cattle and horses. Professor Sand created the illustrations with the intention of publishing a handbook of obstetrics, but due to illness and an early death, this work was never completed. This compilation of historical artworks of dystocia in cattle and horses includes some of these illustrations and is published to honour Professor Sand, with the intention of making his illustrations widely available for the teaching of veterinary obstetrics. [ABSTRACT FROM AUTHOR]

Conventional induction protocol (CIP) of calving in buffaloes employs the intramuscular (IM) administration of dexamethasone (40 mg) and cloprostenol sodium (500 μg). If there is no progression in terms of cervical dilatation, then a second dose of cloprostenol sodium (500 μg) is administered intramuscularly. This protocol possesses certain demerits: (1) a wide range of response time intervals, and (2) increased risk of fetal membrane retention. Considering the cervix as a caudal continuation of the myometrium with its own contractile potential, and the limitations of CIP, we developed intracervical (IC) drug administration route in buffaloes. The proposed technique was evaluated for its use in a total of 22 cases of incomplete cervical dilatation in uterine torsion-affected buffaloes (IC-14 and IM-8). In addition to CIP, the IC group received an intracervical injection of cloprostenol sodium (500 μg) at the start of the experiment whereas the IM group received an extra intramuscular dose of cloprostenol sodium (500 μg) either after 24 h or when no progression in cervical dilatation is noticed. Surprisingly, the average response time during the experiment in the IC group was 5.8 h shorter (p < 0.000) than in the IM group (IC-5.7 ± 0.17 h vs. IM-11.9 ± 0.74 h). The duration from calving to fetal membrane expulsion (IC-12.8 ± 0.60 h vs. IM-17.5 ± 1.40 h; p < 0.002) and incidence of retention of fetal membrane were also less in the IC group (57.1% vs. 87.5%). The proposed intracervical drug administration potentiates cervical dilatation and can be regarded as a safe, effective, and feasible technique for attaining reliable results. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Zoology is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Folia Pomeranae Universitatis Technologiae Stetinensis Agricultura Alimentaria Piscaria et Zootechnica is the property of West Pomeranian University of Technology in Szczecin and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Marine-terminating glaciers cover more than one-fourth of the total glacierized area in the Northern Hemisphere outside the Greenland ice sheet. It is therefore crucial to ensure an adequate representation of these glaciers when projecting large-scale glacier mass changes. We investigate how the introduction of marine frontal processes in the modeling chain influences the results of mass change projections, compared to projections neglecting such processes. We find that including frontal processes reduces the projected glacier mass loss, since incorporating frontal ablation in the model's mass-balance calibration results in a decrease in marine-terminating glaciers' sensitivity to atmospheric temperatures. We also find that retrograde bed slopes lead to increased frontal ablation as the atmosphere warms, while frontal ablation decreases if bed slopes are prograde. These opposing effects have the potential to partly cancel each other when considering large glacier ensembles. Although we do not account for potential future changes in oceanic climate yet, any effect of these would be moderated by around half of today's marine-terminating glaciers becoming land-terminating in the course of the 21st century. While we find a significant influence of ice flow parameters on our results, boundary conditions remain the largest source of uncertainty in our projections. [ABSTRACT FROM AUTHOR]

In Greenland, 87% of the glacierized area terminates in the ocean, but mass lost at the ice‐ocean interface, or frontal ablation, has not yet been fully quantified. Using measurements and models we calculate frontal ablation of Greenland's 213 outlet and 537 peripheral glaciers and find a total frontal ablation of 481.8 ± 24.0 for 2000–2010 and 510.2 ± 18.6 Gt a−1 for 2010–2020. Ice discharge accounted for ∼90% of frontal ablation during both periods, while mass loss due to terminus retreat comprised the remainder. Only 16 glaciers were responsible for the majority (>50%) of frontal ablation from 2010 to 2020. These estimates, along with the climatic‐basal balance, allow for a more complete accounting of Greenland Ice Sheet and peripheral glacier mass balance. In total, Greenland accounted for ∼90% of Northern Hemisphere frontal ablation for 2000–2010 and 2010–2020. Plain Language Summary: We estimate the mass of ice lost from all Greenland glaciers that entered the ocean during each of the last two decades. This ice loss at the front of these marine‐terminating glaciers is called frontal ablation and is approximately equal to the mass of icebergs entering the ocean. Frontal ablation is important because 87% of glacier area in Greenland ends in the ocean, through 750 outlets, and previous work has only approximated frontal ablation. This study quantifies it for the first time, helping to close the mass budget for the Greenland Ice Sheet and better partition its mass balance into components. We find that Greenland accounts for ∼90% of all Northern Hemisphere frontal ablation and, of that contribution, just 17 glaciers for 2000–2010 and 16 glaciers for 2010–2020 account for more than half of total Greenland frontal ablation. Key Points: Frontal ablation of the Greenland Ice Sheet averaged 510.2 ± 18.6 Gt a−1 for 2010–2020, ∼90% of which came from ice dischargeThe frontal ablation we measured is larger than the total mass loss from the ice sheet, indicating a positive climatic‐basal balanceOnly 16 glaciers account for 50% of the total frontal ablation from the Greenland Ice Sheet [ABSTRACT FROM AUTHOR]

Sea level rise contributions from the Pine Island Glacier (PIG) are strongly modulated by the backstress that its floating extension – Pine Island Ice Shelf (PIIS) – exerts on the adjoining grounded ice. The front of PIIS has recently retreated significantly via calving, and satellite and theoretical analyses have suggested further retreat is inevitable. As well as inducing an instantaneous increase in ice flow, retreat of the PIIS front may result in increased ocean melting, by relaxing the topographic barrier to warm ocean water that is currently provided by a prominent seabed ridge. Recently published research (Bradley and others, 2022a) has shown that PIIS may exhibit a strong melting response to calving, with melting close to the PIG grounding line always increasing with ice front retreat. Here, we summarise this research and, additionally, place the results in a glaciological context by comparing the impact of melt-induced and ice-dynamical changes in the ice shelf thinning rate. We find that while PIG is expected to experience rapid acceleration in response to further ice front retreat, the mean instantaneous thinning response is set primarily by changes in melting, rather than ice dynamics. Overall, further ice front retreat is expected to lead to enhanced ice-shelf thinning, with potentially detrimental consequences for ice shelf stability. [ABSTRACT FROM AUTHOR]

Knowledge of frontal ablation from marine-terminating glaciers (i.e., mass lost at the calving face) is critical for constraining glacier mass balance, improving projections of mass change, and identifying the processes that govern frontal mass loss. Here, we discuss the challenges involved in computing frontal ablation and the unique issues pertaining to both glaciers and ice sheets. Frontal ablation estimates require numerous datasets, including glacier terminus area change, thickness, surface velocity, density, and climatic mass balance. Observations and models of these variables have improved over the past decade, but significant gaps and regional discrepancies remain, and better quantification of temporal variability in frontal ablation is needed. Despite major advances in satellite-derived large-scale datasets, large uncertainties remain with respect to ice thickness, depth-averaged velocities, and the bulk density of glacier ice close to calving termini or grounding lines. We suggest ways in which we can move toward globally complete frontal ablation estimates, highlighting areas where we need improved datasets and increased collaboration. [ABSTRACT FROM AUTHOR]

We revise and evaluate frontal ablation fluxes obtained by the Open Global Glacier Model (OGGM) for Greenland's tidewater peripheral glaciers de-coupled from the ice sheet. By making use of new region-wide ice thickness and solid ice discharge data, we re-evaluate model performance and suggest future research directions to improve the ice thickness estimation of glacier models. OGGM is unable to predict individual tidewater glacier dynamics well if it has to rely only on surface mass balance estimates and the assumption of a closed budget to constrain the calving parameterization. Velocity observations are essential to constrain the model and estimate the dynamic mass loss of Greenland's tidewater peripheral glaciers. [ABSTRACT FROM AUTHOR]

Aims of study was to determine the relationship between steaming up with colostrum production at different milking times. The animals used in this research were 36 pregnant Holstein-Friesian (HF) cows. The method used in this research was a case study. Samples were determined with purposive sampling. The selected animal was divided into two groups, T1 (control) and T2 (steaming up). The steaming up was done two weeks prior to calving. The total average of colostrum production from HF cows that were in T2 group was 11.96±2.40 liter/cow/day, while the mean value of colostrum production from HF cows that were in T1 group was 8.05±1.80 liter/cow/day. The average colostrum production that was collected at morning milking from cows in T2 group was 6.38±1.36 liter/cow/day and at afternoon milking was 5.58±1.11 liter/cow/day, significantly higher than T1 group which was 4.22±0.92 liter/cow/day at morning milking and 3.83±0.90 liter/cow/day. The result of the regression equation on morning milking is Y = 2.059 + 2.159x. This means that steaming up treatment can increase colostrum production by as much as 2.159 liters at morning milking. While the result of the regression equation on afternoon milking is Y = 1.753 + 2.078x. This means steaming up treatment can escalate the colostrum production as much as 2.078 at afternoon milking. That equation is used as the basis for estimating the relationship between steaming up with colostrum production at both milking times, with a correlation coefficient (r) between steaming up and colostrum quantity at morning milking is 0.692, which means the relationship is in the strong category. Meanwhile, the relationship between steaming up and colostrum yield at afternoon milking is 0.666, which means the relationship is also in the strong category. It was concluded that steaming up had a very significant effect at both milking times in Holstein-Friesian cows. [ABSTRACT FROM AUTHOR]

Tibetan antelopes (Pantholops hodgsonii) migrate great distances to specific delivery and calving areas. In the current study, we investigated calving site selection and vigilance behaviour during delivery and nursing in migratory female Tibetan antelopes at Zonag Lake. According to observations and analysis, the females were distributed south of Zonag Lake, where vegetation was abundant. We determined their dates of migration (crossing the Qinghai-Tibet Highway observation site), showing a shift of one month during the period from June in 2008 to May 2021. Results also showed that 81.4% of females expressed high vigilance behaviour during calving and nursing compared to those without calves (7.1%). From delivery until calf standing, females were highly vigilant and spent considerable time scanning, with 96% of females showing vigilance behaviour. Females with calves (average 9.94 ± 0.62 s) spent more time on vigilance behaviour than females without calves (average 6.25 ± 1.38 s). Females with newborns spent the greatest amount of time being vigilant (average 51.63 ± 4.24 s). These results not only identify basic Tibetan antelope calving behaviour, but also provide scientific analysis and evidence for further ethological research on female Tibetan antelopes. [ABSTRACT FROM AUTHOR]

The paper presents the results from 2019–2022 of studying the associations of polymorphism of the coenzyme Q9 (COQ9) gene, which affects the energy and metabolic processes in the body, with traits of the reproductive qualities of Holstein heifers. The experimental population was selected from animal analogues (251 heads). DNA testing of allelic polymorphism G → A (guanine → adenine) of the COQ9 gene, which results in changes in oxidative phosphorylation, that affects the respiratory function of mitochondria, was carried out by PCR-RFLP. Two alleles (A, 0.604; G, 0.396) and three genotypes (AA, 36.6%; AG, 48.2%; GG, 15.5%) have been identified in the COQ9–BstMB I gene locus, which indicates genetic biodiversity populations. The chi-square takes on a value well below the critical value (0.05). The population is in genetic equilibrium according to the Hardy-Weinberg law. The traits of the reproductive ability of cows (251 animals) of different genetic groups of the COQ9 gene have been studied. An analysis of the relationship between fertility rates and genotypes of the COQ9 gene showed that individuals with the COQ9AA genotype were characterized by increased live weight during insemination and at calving. Animals with the COQ9AG genotype were characterized by a later age of the first fruitful insemination, while the number of sperm doses spent on them was minimal. The same group of heifers had the shortest calving interval, open day and service period and, as a result, a greater yield of live calves, a high fertility index of Dohi and a reproductive ability coefficient. The data presented in our research prove the influence of genetic factors on the reproductive qualities of cattle, which makes it possible to develop systems for managing the productivity of farm animals based on the use of molecular genetics methods. [ABSTRACT FROM AUTHOR]

A populational, observational and longitudinal‐retrospective study with records of 28 dairy‐specialized and dual‐purpose farms was carried out to compare the productive performance of cows born by embryo transfer (ET), artificial insemination (AI) and natural mating (NM), using the database of Centro Regional de Investigación para la Producción Animal Sostenible (CRIPAS) of cattle herds in Costa Rica. Herds (system × altitude), conception method (ET, AI and NM), genetic background (DSpB: specialized dairy breeds [Bos taurus] and crosses, GYR × HOL: Gyr × Holstein Crossbred and DSpB × BI: crosses between dairy breeds and Bos indicus), year of birth (or at calving), lactation number and days in milk were evaluated for the productive parameters age at first calving (AFC), calving to conception interval (CCI) and lactation milk yield (LMY) using a GLIMMIX procedure on SAS. The AFC, CCI and LMY were affected (p <.0001) by all factors considered in each parameter. ET has lower (p <.0001) AFC in months (33.1) than AI (35.2) and NM (36.44). NM had lower (p =.004) CCI (110 days) than AI or ET (121 days) values which were similar (p >.05). The higher LMY (p <.0001) was observed in ET (4140 kg), compared to AI (3706 kg) and NM (3595 kg). There was no difference between AI and NM. In conclusion, the method of conception in calves affected their future reproduction and production during puberty, postpartum and lactation. The effects on management decisions will require a rigorous economical study to discern whether ET would be a cost‐effective alternative to AI or NM. [ABSTRACT FROM AUTHOR]

Future mass loss projections of the Greenland ice sheet require understanding of the processes at a glacier terminus, especially of iceberg calving. We present detailed and high-rate terrestrial radar interferometer observations of Eqip Sermia and Bowdoin Glacier, two outlet glaciers in Greenland with comparable dimensions and investigate iceberg calving, surface elevation, velocity, strain rates and their links to air temperature, tides and topography. The results reveal that the two glaciers exhibit very different flow and calving behaviour on different timescales. Ice flow driven by a steep surface slope with several topographic steps leads to high velocities, areas of extension and intense crevassing, which triggers frequent but small calving events independent of local velocity gradients. In contrast, ice flow under smooth surface slopes leaves the ice relatively intact, such that sporadic large-scale calving events dominate, which initiate in areas with high shearing. Flow acceleration caused by enhanced meltwater input and tidal velocity variations were observed for terminus sections close to floatation. Firmly grounded terminus sections showed no tidal signal and a weak short-term reaction to air temperature. These results demonstrate reaction timescales to external forcings from hours to months, which are, however, strongly dependent on local terminus geometry. [ABSTRACT FROM AUTHOR]

Basal crevasses are macroscopic structural discontinuities at the base of ice sheets and glaciers that arise by fracture. Motivated by observations and by the mechanics of elastic fracture, we hypothesise that spatial variations in basal stress (in the presence of basal water pressure) can promote and localise basal crevassing. We quantify this process in the theoretical context of linear elastic fracture mechanics. We develop a model evaluating the effect of shear-stress variation on the growth of basal crevasses. Our results indicate that sticky patches promote the propagation of basal crevasses, increase their length of propagation into the ice and, under some conditions, give them curved trajectories that incline upstream. A detailed exploration of the parameter space is conducted to gain a better understanding of the conditions under which sticky-patch-induced basal crevassing is expected beneath ice sheets and glaciers. [ABSTRACT FROM AUTHOR]

This study was designed to deduce the effect of parity and calving season on the resumption of ovarian cyclicity in post-partum Murrah buffaloes. For this study, 102 Murrah buffaloes (primparous: 21; pluriparous: 81) calved between August 2015 and February 2016 were examined by transrectal ultrasonography. The first group of buffaloes between 26- days post-partum were taken and thereafter animals calved every next 10 days were grouped and added. Animals thus progressed and adjudged in 26-35, 36-45, 46-55, 56-65, 66-75, 76-85 and 86-95 days post-partum with an average of 30, 40, 50, 60, 70, 80 and 90 days post-partum, respectively. The day of second examination at 10 days interval of first group of animals also had first examination of second group and the same was followed for all study groups till cyclicity was confirmed in all study animals. In this investigation, 40.20, 65.69 and 81.37 % buffaloes resumed cyclicity within 30, 60 and 90 days post-partum, respectively. Significant (p < 0.0001) difference in resumption of cyclicity between primiparous and pluriparous buffaloes was observed. Onset of cyclicity in pluriparous buffaloes (37.24 ± 1.83 days post-partum) differed significantly (p = 0.0001) than primiparous (59.61 ± 6.10 days post-partum). Also, the onset of cyclicity was evident (p < 0.0001) during pre-breeding (n = 60) and resumption of ovarian cyclicity showed a significant trend (p < 0.0001) in relation to days post-partum. In summary, resumption of ovarian cyclicity differs significantly with parity and season of calving in post-partum Murrah buffaloes. [ABSTRACT FROM AUTHOR]

In seasonal environments, animals should be adapted to match important life‐history traits to when environmental conditions are optimal. Most animal populations therefore reproduce when resource abundance is highest to increase annual reproductive success. When facing variable, and changing, environments animals can display behavioural plasticity to acclimate to changing conditions. Behaviours can further be repeatable. For example, timing of behaviours and life history traits such as timing of reproduction may indicate phenotypic variation. Such variation may buffer animal populations against the consequences of variation and change.Our goal was to quantify plasticity and repeatability in migration and parturition timing in response to timing of snowmelt and green‐up in a migratory herbivore (caribou, Rangifer tarandus, n = 132 ID‐years) and their effect on reproductive success.We used behavioural reaction norms to quantify repeatability in timing of migration and timing of parturition in caribou and their plasticity to timing of spring events, while also quantifying phenotypic covariance between behavioural and life‐history traits.Timing of migration for individual caribou was positively correlated with timing of snowmelt. The timing of parturition for individual caribou varied as a function of inter‐annual variation in timing of snowmelt and green‐up. Repeatability for migration timing was moderate, but low for timing of parturition. Plasticity did not affect reproductive success. We also did not detect any evidence of phenotypic covariance among any traits examined—timing of migration was not correlated with timing of parturition, and neither was there a correlation in the plasticity of these traits.Repeatability in migration timing suggests the possibility that the timing of migration in migratory herbivores could evolve if the repeatability detected in this study has a genetic or otherwise heritable basis, but observed plasticity may obviate the need for an evolutionary response. Our results also suggest that observed shifts in caribou parturition timing are due to plasticity as opposed to an evolutionary response to changing conditions. While this provides some evidence that populations may be buffered from the consequences of climate change via plasticity, a lack of repeatability in parturition timing could impede adaptation as warming increases. [ABSTRACT FROM AUTHOR]

Bali cattle have advantages in terms of adaptation and fertilization rates, but tend to have slow growth rate because the rearing system is still grazing so that livestock growth becomes uncontrollable. This study aims to determine the peak of mating and calving estimation of Bali cattle (Bos sondaicus) that did not experience reproductive disorders, aged 4-7 years, belonging to smallholder farmers. The cattle were reared in semi-arid area of Netemnanu village, South Amfoang district, Kupang regency, Nusa Tenggara Timur. The method used was interviews with farmers, diagnosis of pregnancy through rectal palpation and ultrasonography. The results showed that the pregnancy rate was 86.20% (50/58). Based on pregnancy data, it was known that the peak of mating would occur in December 2021 and estimated calving would reach its peak in September 2022. [ABSTRACT FROM AUTHOR]

Simple Summary: The use of technology to predict calving is increasingly being applied in animal reproduction. In our current study, we tested the hypothesis that there are correlations between facets of ruminating, eating, and locomotion behavior parameters registered by innovative technologies utilized by RumiWatch before and after calving. We found that rumination time, eating time, drinking time, and activity all decreased ten days before calving; drinking gulps decreased on the ninth and second days before calving; and down time decreased two days before calving, thus ensuring that the likelihood of calving is predicted from 10 days prior to the event. The hypothesis for this study was that there are correlations between ruminating, eating, and locomotion behavior parameters registered by the RumiWatch sensors (RWS) before and after calving. The aim was to identify correlations between registered indicators, namely, rumination, eating, and locomotion behavior around the calving period. Some 54 multiparous cows were chosen from the entire herd without previous calving or other health problems. The RWS system recorded a variety of parameters such as rumination time, eating time, drinking time, drinking gulps, bolus, chews per minute, chews per bolus, activity up and down time, temp average, temp minimum, temp maximum, activity change, other chews, ruminate chews, and eating chews. The RWS sensors were placed on the cattle one month before expected calving based on service data and removed ten days after calving. Data were registered 10 days before and 10 days after calving. We found that using the RumiWatch system, rumination time was not the predictor of calving outlined in the literature; rather, drinking time, downtime, and rumen chews gave the most clearcut correlation with the calving period. We suggest that using RumiWatch to combine rumination time, eating time, drinking, activity, and down time characteristics from ten days before calving, it would be possible to construct a sensitive calving alarm; however, considerably more data are needed, not least from primiparous cows not examined here. [ABSTRACT FROM AUTHOR]

The incidence of clinical mastitis (CM) in small and large-scale dairy cow farms can be highly variable and can be affected by age, parity, post-calving status, and atmospheric conditions. The current study aimed to assess the CM-incidence and its association with the post-calving days, number of lactations, season, and number of affected udder quarters in dairy cows in small-scale dairy farms. The study was conducted within one calendar year in 177 small-scale farms with 864 dairy cows. Clinically confirmed CM cows (n=72) were sampled from each udder quarter and processed for bacteriology examination. The CM-positive samples were grouped according to the season (spring, summer, autumn, and winter), the number of days after calving (<90, 90-180, and >180), the number of lactations (1-st, 2-5-th, and >6-th), and the number of affected udder quarters (one, two, three, and four). The CM-positive samples (n=72, 8.3%) were confirmed on bacteriology examination in significantly lower count (n=56, 6.5%). The 2-5-th lactations cows (n=35, 68.6%) were significantly more compared to the first lactation (n=6, 11.8%), and >6-th lactation cows (n=10, 19.6%). CM cows with infection of one udder quarter (n=40, 78.4%) were significantly more than the cows with two (n=6, 11.8%), and four infected quarters (n=5, 9.8%). The CM-incidence in small-scale dairy cow farms in North Macedonia was 8.3% and 6.5% by clinical and bacteriology examination, respectively. The highest CM susceptibility was observed in the cows between the second and fifth lactations. One udder quarter was most frequently affected in CM-positive cases. [ABSTRACT FROM AUTHOR]

The aim of this research was to investigate the effect of drenching with a feed additive on rumination time (RT) and reticuloruminal pH post-partum at a Hungarian large-scale dairy farm. One hundred and sixty-one cows were fitted with a Ruminact© HR-Tag and from these 20 also received SmaXtec© ruminal boli approximately 5 days before calving. Drenching and control groups were established based on calving dates. Animals in the drenching group were dosed three times (Day 0/day of calving/, Day 1, and Day 2 after calving) using a feed additive containing calcium propionate, magnesium sulphate, yeast, potassium chloride and sodium chloride mixed in approximately 25 L of lukewarm water. RT before calving and sensitivity to subacute ruminal acidosis (SARA) were considered in the final analysis. There was a significant decrease in RT in the drenched groups compared to the controls after drenching. Reticuloruminal pH was significantly higher and time below reticuloruminal pH 5.8 remained significantly lower in SARA-tolerant drenched animals on the days of the first and the second drenchings. Drenching temporarily decreased RT in both drenched groups compared to controls. The feed additive had a positive effect on reticuloruminal pH and time below reticuloruminal pH 5.8 in tolerant drenched animals. [ABSTRACT FROM AUTHOR]

Arctic ice shelves have declined over the past several decades, one of many indications of a rapidly changing cryosphere. Here we use a collection of off-nadir Landsat 8 images, a 1978 digital orthophotograph and photogrammetrically derived DEM, satellite altimetry and other data to examine the causes of an Arctic ice-shelf retreat in northernmost Greenland, the Hunt Fjord Ice Shelf (HFIS). HFIS has several distinct provenance regions comprised of glacier-derived ice and corrugated multi-decadal fast ice, with varying ice thicknesses (5–64 m). Available imagery shows little change in HFIS between 1978 and 2012, after which several midsummer calving events occurred (2012, 2016 and 2019) that reduced the HFIS by 42.5 km2 (~56%). Shelf area losses began as the number of surface melt days on the adjacent ice sheet more than doubled relative to the 1980s. Recent calving events also occurred during open-water periods at the ice-shelf front. Prior to mid-2012, there were no calving events during similar open-water periods. HFIS tributary glaciers have thinned by 3–20 m near their grounding zones, and may have accelerated since the 1980s, likely due to increased basal melting from contact with warm Atlantic Water. [ABSTRACT FROM AUTHOR]

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Copyright of Züchtungskunde is the property of Verlag Eugen Ulmer and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Iceberg calving is one of the major mechanisms of ice loss from tidewater glaciers and ice sheets, but obtaining accurate estimates of ice discharge that are both continuous and accurate is a challenging task. Recent results have demonstrated the effective application of passive cryoacoustics – the use of naturally generated sounds to study the cryosphere – to quantify subaerial calving fluxes. However, little is known about the acoustic signatures of submarine calving. This study investigates the underwater noise from 656 subaerial and 162 submarine calving events observed at Hansbreen, Svalbard in the summers of 2016 and 2017. Statistical analysis of the acoustic signal shows that the normalized power of the calving noise is log-normally distributed regardless of the calving mode. However, submarine events can be distinguished from subaerial events by using the shape parameter of the log-normal distribution paired with the calving signal duration. The newly developed classification model may potentially be used for two purposes: (1) to study potential causal relationships between these two calving modes and (2) to separate calving fluxes into subaerial and submarine components. The latter will also require knowledge of the relationship between ice mass and sound spectral level for submarine calving events. [ABSTRACT FROM AUTHOR]

Mass loss from ice shelves is a strong control on grounding-line dynamics. Here we investigate how calving and submarine melt parameterizations affect steady-state grounding-line positions and their stability. Our results indicate that different calving laws with the same melt parameterization result in more diverse steady-state ice-sheet configurations than different melt parameterizations with the same calving law. We show that the backstress at the grounding line depends on the integrated ice-shelf mass flux. Consequently, ice shelves are most sensitive to high melt rates in the vicinity of their grounding lines. For the same shelf-averaged melt rates, different melt parameterizations can lead to very different ice-shelf configurations and grounding-line positions. If the melt rate depends on the slope of the ice-shelf draft, then the positive feedback between increased melting and steepening of the slope can lead to singular melt rates at the ice-shelf front, producing an apparent lower limit of the shelf front thickness as the ice thickness vanishes over a small boundary layer. Our results illustrate that the evolution of marine ice sheets is highly dependent on ice-shelf mass loss mechanisms, and that existing parameterizations can lead to a wide range of modelled grounding-line behaviours. [ABSTRACT FROM AUTHOR]

Little is known about the interplay between the ruminant microbiome and the host during challenging events. This long-term study investigated the ruminal and duodenal microbiome and metabolites during calving as an individual challenge and a lipopolysaccharide-induced systemic inflammation as a standardized challenge. Strong inter- and intra-individual microbiome changes were noted during the entire trial period of 168 days and between the 12 sampling time points. Bifidobacterium increased significantly at 3 days after calving. Both challenges increased the intestinal abundance of fiber-associated taxa, e.g., Butyrivibrio and unclassified Ruminococcaceae. NMR analyses of rumen and duodenum samples identified up to 60 metabolites out of which fatty and amino acids, amines, and urea varied in concentrations triggered by the two challenges. Correlation analyses between these parameters indicated a close connection and dependency of the microbiome with its host. It turns out that the combination of phylogenetic with metabolite information supports the understanding of the true scenario in the forestomach system. The individual stages of the production cycle in dairy cows reveal specific criteria for the interaction pattern between microbial functions and host responses. [ABSTRACT FROM AUTHOR]

Simple Summary: In dairy buffaloes, the efficiency of the milking process mostly depends on the anatomical and physiological differences found in this species when compared to cattle from the genus Bos. Milk quality is influenced by individual and environmental characteristics such as health, diet, handling, and the use of exogenous hormones such as oxytocin, elements that can alter the dam's performance. The present review aims to integrate the anatomical characteristics of the mammary gland and the neurophysiology of milk ejection to understand the milking capacity of the water buffalo. The present review aims to integrate the anatomical characteristics of the mammary gland and the neurophysiology of milk ejection to understand the milking capacity of the water buffalo. Since one of the main uses of this species is milk production, this article will analyze the controversies on the use of oxytocin as a stimulant during milking as well as the existing alternatives that farmers apply to promote correct stimulation during milk letdown. According to the available literature, the efficiency of the milking process, the quality of the milk, and the health of the animals are elements that require the consideration of species-specific characteristics to enhance the performance of buffaloes. The incorporation of technological innovations and competitive strategies could contribute to a better understanding of water buffalo in the milk industry. [ABSTRACT FROM AUTHOR]

Simple Summary: Although the pain associated with parturition performs the primary physiological function of maintaining frequent, strong myometrial contractions, its biological consequences can affect the health of both mother and fetus. Whilst analgesic therapy may be recommended to avoid pain, the evidence indicates that the mechanisms of some analgesic drugs can interfere with the biological process of labor. Opioids and non-steroidal anti-inflammatory drugs have been shown to indirectly inhibit myometrial contractions by decreasing oxytocin secretion, while local analgesics decrease the number of contractions, although its intensity increases, improving maternal performance. This article analyzes the physiological role of pain during labor and the use and efficacy of opioids, non-steroidal anti-inflammatory drugs, and local analgesics in treatments to manage parturition in domestic mammals. This article analyzes the physiological role of pain during parturition in domestic animals, discusses the controversies surrounding the use of opioids, non-steroidal anti-inflammatory drugs (NSAIDs), and local analgesics as treatments during labor, and presents the advantages and disadvantages for mother and offspring. Labor is a potentially stressful and painful event, due to the contractions that promote expulsion of the fetus. During labor, neurotransmitters such as the prostaglandins contribute to the sensitization of oxytocin receptors in the myometrium and the activation of nociceptive fibers, thus supporting the physiological role of pain. Endogenously, the body secretes opioid peptides that modulate harmful stimuli and, at the same time, can inhibit oxytocin's action in the myometrium. Treating pain during the different stages of parturition is an option that can help prevent such consequences as tachycardia, changes in breathing patterns, and respiratory acidosis, all of which can harm the wellbeing of offspring. However, studies have found that some analgesics can promote myometrial contractility, increase expulsion time, affect fetal circulation, and alter mother–offspring recognition due to hypnotic effects. Other data, however, indicate that reducing the number of uterine contractions with analgesics increases their potency, thus improving maternal performance. Managing pain during labor requires understanding the tocolytic properties of analgesics and their advantages in preventing the consequences of pain. [ABSTRACT FROM AUTHOR]

Iceberg calving, the process where icebergs detach from glaciers, remains poorly understood. Moreover, few parameterizations of the calving process can easily be integrated into numerical models to accurately capture observations, resulting in large uncertainties in projected sea level rise. Recent efforts have focused on estimating crevasse depths assuming tensile failure occurs when crevasses fully penetrate the glacier thickness. However, these approaches often ignore the role of advecting crevasses on calculations of crevasse depth. Here, we examine a more general crevasse depth calving model that includes crevasse advection. We apply this model to idealized prograde and retrograde bed geometries as well as a prograde geometry with a sill. Neglecting crevasse advection results in steady glacier advance and ice tongue formation for all ice temperatures, sliding law coefficients and constant slope bed geometries considered. In contrast, crevasse advection suppresses ice tongue formation and increases calving rates, leading to glacier retreat. Furthermore, crevasse advection allows a grounded calving front to stabilize on top of sills. These results suggest that crevasse advection can radically alter calving rates and hint that future parameterizations of fracture and failure need to more carefully consider the lifecycle of crevasses and the role this plays in the calving process. [ABSTRACT FROM AUTHOR]

Upernavik Isstrøm, a marine glacier undergoing rapid retreat, is simulated by forcing a numerical model with ocean-driven melt. A review of processes driving retreat led us to hypothesize that a glacier undergoing rapid retreat may be less sensitive to perturbations in the balance of forces than a glacier that is undergoing moderate changes or a glacier in steady state. Numerical experiments suggest this is not the case, and that a system in rapid retreat is as sensitive to basal traction perturbations as a system that is near to steady state. This result is important when considering other glacier systems experiencing marine-forced retreat. While the ice–ocean interface is of primary importance, additional perturbations from meltwater-forced decoupling of the glacier from its bed continue to feature in glacier dynamics. [ABSTRACT FROM AUTHOR]

The decline of Caribou (Rangifer tarandus) is mainly attributed to anthropogenic disturbance from resource development (i.e., logging, oil and gas extraction), which causes habitat loss and increased predation risk. Natural landscape disturbance, particularly from fire, can have similar effects, and cumulative effects from disturbance have been associated with lower neonate recruitment. Our objective was to evaluate the potential effects of land cover types on resource selection by females, with an emphasis on clear-cuts and fire, during the calving season (May-June) in three neighbouring herds (Middle Ridge, Gaff Topsails, and Pot Hill) on insular Newfoundland, Canada, and compare results with pre-existing information on calf recruitment. We applied a resource selection framework to analyze location data collected from global positioning system collars between 2007-2010 and estimate relative probability of use for different cover types. Recruitment was lowest in Pot Hill, where =10-year old clear-cuts were favoured, whereas recruitment was highest in Middle Ridge and Gaff Topsails, where females favoured burns, suggesting that burns could be more beneficial to Caribou fitness. Further investigation will be needed to more closely examine how anthropogenic versus natural disturbance affects Caribou fitness in Newfoundland and improve our understanding of important habitat for calving females. [ABSTRACT FROM AUTHOR]

Simple Summary: A fetal catheterization is an efficient tool allowing longitudinal in vivo studies on hormonal and metabolic changes, including fetal blood gases and acid-base changes. These surgical techniques made it possible to take blood samples daily under aseptic conditions to determine arterial and/or venous blood samples for acid-base variables (like pH, blood gas tensions: partial pressure of carbon dioxide and partial pressure of oxygen, oxygen saturation, bicarbonate concentration, total carbon dioxide, and base excess). All these examinations may contribute to a better understanding of the physiological changes that occur during calving, which may help reach a significant reduction in losses caused by perinatal mortality, which is still high today. The objective of the present study was to evaluate the changes in maternal and fetal arterial acid-base variables withdrawn from catheterized dams and fetuses during the last days before and during calving. The average gestation length in nine cows with chronically catheterized fetuses was 285 ± 10 (SD) days. The arterial acid-base variables of a catheterized dam and fetus were very stable during late gestation. Four newborn calves showed small differences between prenatal and postnatal pH values (−0.035). At the same time, pCO2 values started to increase significantly (p = 0.02), indicating a shift towards physiological respiratory acidosis during calving. The partial pressure of oxygen and oxygen saturation values showed some non-significant improvements immediately after birth, while the other acid-base parameters did not differ. The remaining five newborn calves showed a significant decrease in arterial blood pH (p < 0.01) and BE (p = 0.01), while pCO2 tended to be higher (p = 0.06), indicating a shift towards physiological respiratory and metabolic acidosis, while the other acid-base parameters hardly differed. It is essential to mention that physiological (n = 2) and mild metabolic acidosis (n = 2) developed gradually in four newborn calves during the second stage of calving, lasting about ≤ 2 h. In contrast, in the remaining newborn calf the physiological metabolic acidosis developed during the last 3 min of birth because immediately before birth, the BE value was 0.4 mmol/L. After birth, it was −5.4 mmol/L. The results indicate that the acid-base variables may start to move gradually in the direction of expressed respiratory and metabolic acidosis only after appearing the amniotic sac and fetal feet in the vulva during the second stage of labor; therefore, it is essential to complete obstetrical assistance in time. [ABSTRACT FROM AUTHOR]

Knowledge of frontal ablation from marine-terminating glaciers (i.e., mass lost at the calving face) is critical for constraining glacier mass balance, improving projections of mass change, and identifying the processes that govern frontal mass loss. Here, we discuss the challenges involved in computing frontal ablation and the unique issues pertaining to both glaciers and ice sheets. Frontal ablation estimates require numerous datasets, including glacier terminus area change, thickness, surface velocity, density, and climatic mass balance. Observations and models of these variables have improved over the past decade, but significant gaps and regional discrepancies remain, and better quantification of temporal variability in frontal ablation is needed. Despite major advances in satellite-derived large-scale datasets, large uncertainties remain with respect to ice thickness, depth-averaged velocities, and the bulk density of glacier ice close to calving termini or grounding lines. We suggest ways in which we can move toward globally complete frontal ablation estimates, highlighting areas where we need improved datasets and increased collaboration. [ABSTRACT FROM AUTHOR]

Sea level rise contributions from the Pine Island Glacier (PIG) are strongly modulated by the backstress that its floating extension – Pine Island Ice Shelf (PIIS) – exerts on the adjoining grounded ice. The front of PIIS has recently retreated significantly via calving, and satellite and theoretical analyses have suggested further retreat is inevitable. As well as inducing an instantaneous increase in ice flow, retreat of the PIIS front may result in increased ocean melting, by relaxing the topographic barrier to warm ocean water that is currently provided by a prominent seabed ridge. Recently published research (Bradley and others, 2022a) has shown that PIIS may exhibit a strong melting response to calving, with melting close to the PIG grounding line always increasing with ice front retreat. Here, we summarise this research and, additionally, place the results in a glaciological context by comparing the impact of melt-induced and ice-dynamical changes in the ice shelf thinning rate. We find that while PIG is expected to experience rapid acceleration in response to further ice front retreat, the mean instantaneous thinning response is set primarily by changes in melting, rather than ice dynamics. Overall, further ice front retreat is expected to lead to enhanced ice-shelf thinning, with potentially detrimental consequences for ice shelf stability. [ABSTRACT FROM AUTHOR]

We revise and evaluate frontal ablation fluxes obtained by the Open Global Glacier Model (OGGM) for Greenland's tidewater peripheral glaciers de-coupled from the ice sheet. By making use of new region-wide ice thickness and solid ice discharge data, we re-evaluate model performance and suggest future research directions to improve the ice thickness estimation of glacier models. OGGM is unable to predict individual tidewater glacier dynamics well if it has to rely only on surface mass balance estimates and the assumption of a closed budget to constrain the calving parameterization. Velocity observations are essential to constrain the model and estimate the dynamic mass loss of Greenland's tidewater peripheral glaciers. [ABSTRACT FROM AUTHOR]

The combination of the Pine Island Ice Shelf (PIIS) draft and a seabed ridge beneath it form a topographic barrier, restricting access of warm Circumpolar Deep Water to a cavity inshore of the ridge, thus exerting an important control on PIIS basal ablation. In addition, PIIS has recently experienced several large calving events and further calving could significantly alter the cavity geometry. Changes in the ice front location, together with changes in ice thickness, might relax the topographic barrier and thus significantly change basal melt rates. Here, we consider the impact of past, and possible future, calving events on PIIS melt rates. We use a high‐resolution ocean model to simulate melt rates in both an idealized domain whose geometry captures the salient features of Pine Island Glacier, and a realistic geometry accurately resembling it, to explore how calving affects melt rates. The idealized simulations reveal that the melt response to calving has a sensitive dependence on the thickness of the gap between PIIS and the seabed ridge and inform our interpretation of the realistic simulations, which suggest that PIIS melt rates did not respond significantly to recent calving. However, the mean melt rate increases approximately linearly with further calving, and is amplified by approximately 10% relative to present day once the ice front reaches the ridge‐crest, taking less than one decade if calving maintains its present rate. This provides strong evidence that calving may represent an important, but as yet unexplored, contribution to the ice‐ocean sensitivity of the West Antarctic Ice Sheet. Plain Language Summary: The seabed beneath Pine Island Ice Shelf (PIIS)—the floating extension of Pine Island Glacier—features a large ridge. The combination of this seabed ridge and ice shelf above it reduce the amount of relatively warm water that is able to reach the ice shelf, therefore restricting the amount of ice shelf melting that can take place. However, the ice shelf has also lost large sections from its front in recent years, in a process referred to as calving. In this paper, we investigate the combined effect of these two processes: how does calving affect the melt rates on PIIS? Using numerical simulations of the ocean flow beneath the ice shelf, we identify a potentially high sensitivity of melt rates to calving, depending on the cavity geometry. This sensitivity is primarily related to changes in the flow strength in the cavity inshore of the ridge. In addition, our simulations suggest that the melt rate will have an approximately linear dependence on the distance that the ice front retreats in further calving events. These results provide strong evidence that changes in the melting of ice shelves in response to calving might represent an important contribution to the response of West Antarctica in a changing climate. Key Points: Melting of Pine Island Ice Shelf is sensitive to calving because of a seabed ridge beneath it which restricts warm water access to the shelfThe melt response to calving has a strong sensitivity to the cavity geometry and results primarily from circulation changesCalving may be an important contribution to the ice‐ocean sensitivity of the Antarctic Ice Sheet [ABSTRACT FROM AUTHOR]

Context: Neonate management remains a key issue in extensive beef production systems where producers are faced with substantial environmental and management challenges that limit their ability to monitor and manage livestock in a timely manner. Parturition is a critical event and can affect the calf health and survival, particularly in the perinatal period (up to 48 h after birth). As such, monitoring parturition using precision livestock technologies may provide producers with additional tools to manage their cattle and mitigate the impacts of neonatal mortality in extensive beef systems. Aims: The purpose of this study was to determine whether data from a global navigation satellite system (GNSS) collar could be used to detect parturition events in extensively grazed beef cattle. Methods: Forty-eight Bos taurus cows (583.5 kg body weight ± 9.25 s.e.m.) were allocated to a 28 ha paddock between 8 January 2021 and 6 March 2021 during the calving season. Thirty of the animals were fitted with GNSS-equipped collars (Smart Paddock, Vic., Australia) that captured data at 10 min intervals. Parturition events were recorded daily by visual observation. Collected data were used to calculate key predictive features related to calving behaviour. Derived features were compared and assessed for changes in the period surrounding parturition. Key results: Increases were observed in distance to nearest neighbour and to herd aggregate features, and decreases were observed in paddock utilisation and distance travelled features in the lead-up to calving (P < 0.05). Furthermore, the number of animals within a 20 m radius decreased significantly (P < 0.05) in the lead up to parturition, supporting known isolation behaviours. Conclusions: With further development of predictive algorithms, on-animal sensors may be valuable in the prediction of calving events in extensive beef production systems. Implications: Remote management and monitoring with on-animal sensor technologies, such as GNSS collars and tags, will provide producers with an additional means of monitoring their animals, while overcoming many of the management challenges associated with extensive grazing operations. Reproductive efficiency is a performance indicator in extensive beef systems. Calving represents a critical management period that would benefit from increased observational capacity. Precision livestock technologies offer opportunities to better monitor and manage extensively grazed cattle, but more algorithms are needed to detect behaviours and physiological changes. This study used a commercial on-animal sensor to evaluate the value of global navigation satellite system-derived features in parturition detection algorithms. Results indicated both social interaction and spatial utilisation features are good candidates for algorithm development. [ABSTRACT FROM AUTHOR]

We present the first fully coupled 3D full-Stokes model of a tidewater glacier, incorporating ice flow, subglacial hydrology, plume-induced frontal melting and calving. We apply the model to Store Glacier (Sermeq Kujalleq) in west Greenland to simulate a year of high melt (2012) and one of low melt (2017). In terms of modelled hydrology, we find perennial channels extending 5 km inland from the terminus and up to 41 and 29 km inland in summer 2012 and 2017, respectively. We also report a hydrodynamic feedback that suppresses channel growth under thicker ice inland and allows water to be stored in the distributed system. At the terminus, we find hydrodynamic feedbacks exert a major control on calving through their impact on velocity. We show that 2012 marked a year in which Store Glacier developed a fully channelised drainage system, unlike 2017, where it remained only partially developed. This contrast in modelled behaviour indicates that tidewater glaciers can experience a strong hydrological, as well as oceanic, control, which is consistent with observations showing glaciers switching between types of behaviour. The fully coupled nature of the model allows us to demonstrate the likely lack of any hydrological or ice-dynamic memory at Store Glacier. [ABSTRACT FROM AUTHOR]

Ice shelves regulate the stability of marine ice sheets. We track fractures on Pine Island Glacier, a quickly accelerating glacier in West Antarctica that contributes more to sea level rise than any other glacier. Using an on‐ice seismic network deployed from 2012 to 2014, we catalog icequakes that dominantly consist of flexural gravity waves. Icequakes occur near the rift tip and in two distinct areas of the shear margin, and TerraSAR‐X imagery shows significant fracture in each source region. Rift‐tip icequakes increase with ice speed, linking rift fracture to glaciological stresses and/or localized thinning. Using a simple flexural gravity wave model, we deconvolve wave propagation effects to estimate icequake source durations of 19.5–50.0 s and transient loads of 3.8–14.0 kPa corresponding to 4.3–15.9 m of crevasse growth per icequake. These long‐source durations suggest that water flow may limit the rate of crevasse opening. Plain Language Summary: Large shelves of floating ice strengthen glaciers in Antarctica, helping to protect against rapid sea level rise that can occur when glaciers flow into the ocean. Ice shelves can collapse through rapid cracking (synonym of fracturing), but it is difficult to directly observe cracking on ice shelves. In this paper, we track cracks on Pine Island Glacier, an ice shelf in Antarctica that is particularly vulnerable to collapse. We see cracks in pictures taken by satellites. Cracking causes the ice shelf to shake up and down, which we record using the same equipment that records earthquakes. We record shaking located at a set of cracks at the side of the ice shelf and at the tip of a single massive crack called a rift. Rift cracking seems related to the speed that the ice shelf is flowing. We also use a computer simulation of shaking to learn about the details of the crack process. Our simulation suggests that the crack process might be more complicated than a single crack opening evenly at a constant rate. Key Points: Fracture at Pine Island Glacier generates flexural gravity waves, a wave type related to interaction between a floating plate and supporting fluidRift‐tip seismicity rate increases with ice speed either due to changes in the underlying ice shelf stress state or localized thinningRecorded flexural gravity waves are consistent with a point load of ∼10 kPa applied over ∼30s, corresponding to ∼10m of vertical cracking [ABSTRACT FROM AUTHOR]

The present study surveyed that the prevalence of subclinical and clinical ketosis in cattle was assessed in and around Bikaner; a total of 200 cows after parturition were examined. The overall prevalence of clinical ketosis amongst post-parturient cows was 11.50%, while 23.50% for subclinical ketosis. Prevalence of clinical and subclinical ketosis in cows with relation to breed was the highest in Holstein Friesian crossbred cows (17.58%), while the lowest in Rathi cows (05%). Prevalence in relation to the age was the highest in 8–9 years of age (13.79% and 29.31%) and the lowest in >9 years of age (4.76% and 9.52%). Prevalence in relation to number of lactation/calving was the highest in fourth lactation (14.29% and 30.36%) and the lowest in first lactation (2.86% and 11.43%). Out of 11.50% cases of clinical ketosis, the highest prevalence was recorded (30.43%) during 8–14 days of lactation; similarly, out of 23.50% cases of subclinical ketosis, the highest prevalence was recorded (29.79%) during 8–14 days of lactation. Month-wise prevalence of clinical and subclinical ketosis was the highest in December that is 26.09% and 23.40%, while the lowest in August 4.35% and 2.13%. [ABSTRACT FROM AUTHOR]

Over the past decade, one of the largest contributors to total ice discharge across the Greenland ice sheet, Helheim Glacier, has experienced large fluctuations in ice velocity. In this study, we simulate the dynamics of Helheim, from 2007 to 2020, using the Ice‐sheet and Sea‐level System Model to identify the drivers of these large changes in ice discharge. By quantifying the impact of individual external forcing and model parameters on Helheim's modeled velocity, we find that the position of the calving front alone explains the dynamic variability of the glacier, as it has a direct and large impact on Helheim's ice velocity. The seasonal to inter‐annual variability of Helheim Glacier is, however, relatively insensitive to the choice of friction law or ice rheology factor. This study shows that more research on calving dynamics and ice–ocean interactions is required to project the future of this sector of Greenland. Plain Language Summary: At least half of today's mass loss of the Greenland ice sheet is due to the acceleration and retreat of tidewater glaciers. Over the past decade, Helheim Glacier in southeast Greenland has experienced large fluctuations in its flow speed, varying sometimes by more than 2,000 m/yr within a single year. It is still unclear which physical processes are responsible for the fluctuations in ice speed of Helheim Glacier and how much they contribute individually. In this study, we use a novel numerical technique to simulate Helheim Glacier from 2007 to 2020 to investigate the role of some of the physical processes that have been proposed to potentially drive this variability in ice speed. By comparing the solutions of the numerical model to observations of ice speed, we find that the terminus position is the main control of the ice motion at Helheim Glacier. Key Points: Calving has been controlling Helheim's speed variability since 2007Averaging the calving rate over 60 days does not change the glacier behavior significantlyConstraining a calving law is critical to model the future of Helheim's mass balance [ABSTRACT FROM AUTHOR]