Search Results (111)

This study investigated the effects of different forage-to-concentrate (F:C) ratios during cold-season supplementation on growth performance, serum biochemical parameters, hormone levels, and antioxidant capacity in yak calves on the Qinghai–Tibet Plateau. Eighteen 8-months-old male yaks with similar body weights (110.01 ± 2.08 kg) were randomly assigned to two groups receiving diets with high (F:C = 7:3) or low (F:C = 3:7) forage. The trial lasted 60 days, including early (days 0–30) and late (days 31–60) experimental stages. Body weight was measured, and serum samples were collected on days 30 and 60 for biochemical and hormonal analyses. Yaks in the low-forage group showed significantly greater average daily gain during both stages and the entire experiment (p < 0.05), with a 7.92% increase in final body weight. Serum total protein and globulin levels were significantly higher in the low-forage group throughout the trial (p < 0.05 or p < 0.01), while other biochemical parameters remained unaffected. Growth hormone concentrations were significantly elevated in the low-forage group at both stages (p < 0.05). Additionally, malondialdehyde levels tended to decrease in the early stage (p = 0.056), and total antioxidant capacity was significantly lower in the late experimental stage (p = 0.040) in the low-forage group. A higher net economic benefit was observed in the group fed an F:C ratio of 3:7 than in the 7:3 group. These findings suggest that cold-season supplementation with a low-forage diet improves growth performance and protein utilization in yak calves but may negatively impact antioxidant status. An optimal F:C balance should therefore be considered to support both performance and health in yak husbandry under harsh environmental conditions. Full article

Although the ultimate drivers of bat fatalities at wind turbines are still not well understood, the foraging behavior of insectivorous bats puts them at increased risk of collision with rotating blades. Wind energy facilities are commonly located in agriculture fields where bats can exploit periodic superabundant insect emergence events in the late summer and early autumn. Thermal imaging, acoustic monitoring, and bat carcass stomach content analyses show that bats prey upon insects on and near wind turbine towers. Studies have shown a positive association between insect abundance and bat activity, including in agricultural systems. We conducted a systematic review of bat diets for four common bat species in the Midwest and northern Great Plains to synthesize existing knowledge across species, assess the extent to which these bat focal species consume crop pests, and evaluate the potential for crop pest emergence models to predict temporal and spatial patterns of bat fatalities in this region. Big brown bats and eastern red bats consumed a variety of crop pests, including some for which emergence models may be available. In contrast, there were few studies for hoary bats or silver-haired bats, and the dietary evidence available has insufficient taxonomic resolution to conclude that crop pests were consumed. To augment existing data and illuminate relationships, we recommend that genetic diet analyses for bats, specifically hoary and silver-haired, be conducted in the late summer and autumn in this region. The results of these studies may provide additional candidate insect models to evaluate for predicting bat fatalities at wind turbines and clarify if the superabundant insect emergence hypothesis warrants further investigation. Full article

Background/Objectives: Global warming and rising CO₂ concentrations pose significant challenges to plant systems. Amid these pressures, this study contributes to understanding how tropical species respond by simultaneously evaluating reproductive and genetic traits. It specifically investigates the effects of maternal exposure to warming and elevated CO₂ on progeny physiology, genetic diversity, and population structure in Stylosanthes capitata, a resilient forage legume native to Brazil. Methods: Maternal plants were cultivated under controlled treatments, including ambient conditions (control), elevated CO₂ at 600 ppm (eCO₂), elevated temperature at +2 °C (eTE), and their combined exposure (eTEeCO₂), within a Trop-T-FACE field facility (Temperature Free-Air Controlled Enhancement and Free-Air Carbon Dioxide Enrichment). Seed traits (seeds per inflorescence, hundred-seed mass, abortion, non-viable seeds, coat color, germination at 32, 40, 71 weeks) and abnormal seedling rates were quantified. Genetic diversity metrics included the average (A) and effective (Ae) number of alleles, observed (Ho) and expected (He) heterozygosity, and inbreeding coefficient (Fis). Population structure was assessed using Principal Coordinates Analysis (PCoA), Analysis of Molecular Variance (AMOVA), number of migrants per generation (Nm), and genetic differentiation index (Fst). Two- and three-way Analysis of Variance (ANOVA) were used to evaluate factor effects. Results: Compared to control conditions, warming increased seeds per inflorescence (+46%), reduced abortion (−42.9%), non-viable seeds (−57%), and altered coat color. The germination speed index (GSI +23.5%) and germination rate (Gr +11%) improved with warming; combined treatments decreased germination time (GT −9.6%). Storage preserved germination traits, with warming enhancing performance over time and reducing abnormal seedlings (−54.5%). Conversely, elevated CO₂ shortened GSI in late stages, impairing germination efficiency. Warming reduced Ae (−35%), He (−20%), and raised Fis (maternal 0.50, progeny 0.58), consistent with the species’ mixed mating system; A and Ho were unaffected. Allele frequency shifts suggested selective pressure under eTE. Warming induced slight structure in PCoA, and AMOVA detected 1% (maternal) and 9% (progeny) variation. Fst = 0.06 and Nm = 3.8 imply environmental influence without isolation. Conclusions: Warming significantly shapes seed quality, reproductive success, and genetic diversity in S. capitata. Improved reproduction and germination suggest adaptive advantages, but higher inbreeding and reduced diversity may constrain long-term resilience. The findings underscore the need for genetic monitoring and broader genetic bases in cultivars confronting environmental stressors. Full article

Three purple prairie clover (PPC; Dalea purpurea Vent.) varieties, namely Common seed (CS), AC Lamour (ACL) and Bismarck (BIS), were established in plots of irrigated land (rain-fed plus irrigation, Lethbridge, AB) and dryland (rain-fed only, Swift Current, SK) to assess its agronomic characteristics and nutritive value under different ecoclimate and growing conditions in Western Canada. Each seed source was replicated in four test plots arranged as a randomized complete block design at each experimental site. Forage mass on dry matter (DM) basis, canopy height, proportions of leaf and stem and nutritive value were determined at vegetative (VEG), full flower (FF) and late flower (LF) phenological stages. The forage masses of the three PPC varieties were similar (p < 0.05) at each phenological stage with the mean values for VFG, FF and LF being 4739, 4988 and 6753 kg DM/ha under the Lethbridge irrigated conditions, and 1423, 2014 and 2297 kg DM/ha under the Swift Current dryland conditions. The forage mass was higher (p < 0.001) under Lethbridge irrigation than under Swift Current dryland conditions and increased (p < 0.05) with maturity. The three varieties had similar concentrations of organic matter (OM), neutral detergent fibre (NDF), acid detergent fibre (ADF) and crude protein (CP) and in vitro DM digestibility (DMD) at each phenological stage, but CP concentration and in vitro DMD decreased (p < 0.001) whilst NDF and ADF concentration increased (p < 0.001) with maturity. Purple prairie clover grown at Lethbridge irrigated land had higher (p < 0.001) DMD, OM and CP, but lower (p < 0.001) NDF, ADF and condensed tannin concentrations than that grown at Swift Current dryland conditions. These results indicate that PPC has great potential as an alternative legume forage for the cattle industry. Full article

Debates about prehistoric Amazonian subsistence, social organization, and landscape use have ranged from ethnographically based characterizations of relatively mobile foragers to archaeological evidence that suggests sedentary agriculturalists. Recently, great antiquity of settled agriculture and complex social organization has been asserted for portions of the northern Amazon. However, the role of theory and inferences drawn from habitat diversity have receded in these debates. This paper synthesizes the current literature regarding long-term evolutionary changes in Amazon Basin societies with an archaeological case study from mound-building sites of Guyana and ethnoarchaeological data from Venezuelan forager–gardeners to develop a hypothesis regarding the critical role of habitat, aquatic resources, and seasonality in the transition from intensified foraging to cultivation. Full article

Forty multiparous Nellore cows, with an average body weight, body condition score, and gestation days of 533 ± 32 kg, 5.7 ± 0.4 points, and 198 days, respectively, were managed under continuous grazing on a Urochloa decumbens pasture and either received or did not receive 1 kg/day of supplement varying in the levels of inclusion of dried distillers grains (DDG) (Control, 0% DDG, 42% DDG, or 84% DDG) during the last trimester of gestation. The objective was to evaluate the effects of prepartum DDG supplementation on performance, reproduction, fetal development, and calf performance. A quadratic effect of supplementation on BW variation pre- and postpartum was observed (p < 0.05), with cows treated with 42% DDG showing higher BW gain prepartum and low BW loss postpartum. Cows supplemented with 42% DDG had lower levels of non-esterified fatty acids and β-hydroxybutyrate prepartum (p < 0.05). However, body weight-related metrics, such as condition score, carcass traits, and metabolic indicators, varied only by measurement day (p < 0.05). No effect of supplementation was observed on fetal development, calf metabolic profile, milk yield, or postnatal calf performance (p > 0.05). It is recommended to include up to 42% DDG in supplements for beef cows during late gestation grazing on low-quality tropical forage conditions. Full article

Precise detection of potato diseases is critical for food security, yet traditional image segmentation methods struggle with challenges including uneven illumination, background noise, and the gradual color transitions of lesions under complex field conditions. Therefore, a collaborative segmentation framework of Otsu and Sobel edge detection based on the beluga whale optimization algorithm with a danger sensing mechanism (DSBWO) is proposed. The method introduces an S-shaped control parameter, a danger sensing mechanism, a dynamic foraging strategy, and an improved whale fall model to enhance global search ability, prevent premature convergence, and improve solution quality. DSBWO demonstrates superior optimization performance on the CEC2017 benchmark, with faster convergence and higher accuracy than other algorithms. Experiments on the Berkeley Segmentation Dataset and potato early/late blight images show that DSBWO achieves excellent segmentation performance across multiple evaluation metrics. Specifically, it reaches a maximum IoU of 0.8797, outperforming JSBWO (0.8482) and PSOSHO (0.8503), while maintaining competitive PSNR and SSIM values. Even under different Gaussian noise levels, DSBWO maintains stable segmentation accuracy and low CPU time, confirming its robustness. These findings suggest that DSBWO provides a reliable and efficient solution for automatic crop disease monitoring and can be extended to other smart agriculture applications. Full article

The consumption of forages high in slow-degradable carbohydrates by dairy cattle leads to greater ruminal acetate production, which benefits milk fat content. Although tropical grasses are typically rich in fibrous materials, the milk fat content of dairy cows in Southeast Asia is low. Here, we investigate the effects of the species and harvest time of three common tropical grasses (Guinea, King, and Mulato II) harvested at three instances (early, normal, late) on in sacco degradation kinetics and in vitro gas production (IVGP) characteristics. Grass samples were subjected to (1) chemical analysis, (2) a fully automated in vitro gas recording system using rumen fluid to measure fermentation characteristics over 72 h, and (3) in sacco degradation using the nylon bag technique, employing seven incubation times up to 336 h. Forage quality decreased with maturity, as reflected in changes to digestibility and fiber content. Overall, early harvested grasses yielded the highest total gas production (311 ± 12.5 mL/g OM) followed by normal (300 ± 45.7 mL/g OM) and late (273 ± 19.5 mL/g OM) harvested grasses. The in vitro fermentable fraction (A1 + A2) was the highest for early harvested grasses, with the A2 parameter, relevant for milk fat content, being the highest for Guinea (81.6% A2/(A1 + A2)) and the lowest for King grass (71.0% A2/(A1 + A2)). Consequently, early harvested Guinea had the longest incubation times (10.5 h) and lowest fermentation rates (Rmax2 = 12.8 mL/g OM/h). Regression analysis showed relationships between NDF content and degradability. Harvesting tropical grass earlier than customarily practiced enhanced forage quality and ruminal degradability. Of the three grasses studied, each at three levels of maturity, early harvested Guinea grass was the most promising candidate for improving milk fat content in Southeast Asian dairy cows. This grass showed a high fermentable OM content, with a large proportion of slow-degradable carbohydrates. Full article

The small-molecule compound fipexide (FPX) has been shown to promote callus formation in several plants, but its effects on forage crops remain unexplored, and its molecular mechanism is not yet fully understood. In this study, we evaluated FPX-induced callus formation from seeds for up to four weeks in four elite cultivars of Medicago sativa, finding it to be faster than the classical 2,4-D/6-BA treatment for the first two weeks. Notably, the cellular organization of FPX-induced calli differed from those induced by 2,4-D/6-BA by showing almost no conducting tissues. Comparative transcriptome analysis revealed dynamic gene expression changes during the early and late stages of callus induction, such as multicellular organism development and response to auxin. Interestingly, in both M. sativa and Arabidopsis, FPX regulates a group of small auxin upregulated RNA (SAUR) family genes, which are known to fine-tune growth in response to internal and external signals. This suggests a potential evolutionary conserved molecular mechanism underlying FPX-induced callus formation across plant species. Full article

The increasing demand for high-quality forage alternatives necessitates the exploration of novel feed resources such as giant juncao (GJ). This study evaluated the feasibility of giant juncao (GJ) as silage by analyzing its fermentation products, bacterial community, and metabolic profiles during ensiling. After the natural fermentation of giant juncao (NGJ) for 1, 3, 7, 15, 30, and 60 days, a random sampling of NGJ was conducted to analyze its chemical composition, fermentation parameters, and microbial number. Fresh, 3-day, and 60-day ensiled GJ were further analyzed via high-throughput sequencing and KEGG functional prediction. Following 60 days of ensiling, NGJ displayed acetate-type fermentation with high acetic acid and ammonia nitrogen concentrations, and low lactic acid concentration and the ratio of lactic-to-acetic acid. A microbial community analysis indicated Weissella as the predominant genus during the initial fermentation phase (3-day NGJ), whereas Lactobacillus emerged as the dominant taxonomic group in the late-stage fermentation (60-day NGJ). A comparative functional analysis revealed statistically significant divergences (p < 0.05) in KEGG pathway distributions between fresh and ensiled GJ. The ensiling process notably inhibited pathways associated with lipid synthesis, cofactor and vitamin metabolism, energy production, and amino acid utilization while concurrently enhancing carbohydrate and nucleotide metabolic activities. A nutritional evaluation confirmed GJ’s suitability as a sustainable silage maize alternative, with favorable water-soluble carbohydrate (8.57% DM) and crude protein (14.6% DM) levels. To ensure optimal preservation efficacy, the experimental findings emphasize the necessity of a minimum 30-day fermentation period for stabilizing GJ silage quality. These findings offer valuable insight into the microbial and metabolic mechanisms of high-moisture silage fermentation. Full article

A large data set of new and previously published measurements of δ¹³C values derived from tooth enamel (n = 223, of which 93 are new) are compiled to explore patterns of foraging area preferences of Late Cretaceous mosasaurid squamates over evolutionary time scales (~93–66 Ma). Our results indicate that small-bodied halisaurines are restricted to a relatively nearshore range, overlapping the lower end of the range of plioplatecarpines and some mosasaurine taxa. Most moderately sized plioplatecarpines occupy a relatively narrow foraging area in much of the nearshore and proximal offshore marine foraging area for the majority of their existence. Tylosaurines exhibit a greater offshore marine range than plioplatecarpines, consistent with their large body size and the robustness of their feeding apparatus. The largest tylosaurine taxa are replaced by Mosasaurus in the Late Campanian–Maastrichtian in the offshore foraging range. Mosasaurine taxa are found to occupy the broadest range of foraging areas, but their ranges are taxonomically segregated, consistent with adult body size and the diversity of feeding adaptations such as tooth morphologies and skull architecture seen in that subfamily. Where foraging areas of multiple taxa overlap, differences are typically in tooth form, reflecting prey preference or feeding niche. Foraging area occupation by multiple taxa with similar tooth forms suggests that other factors such as body size and prey acquisition style may have allowed for the finer partitioning of resources. Deep diving and long submergence may have also contributed to the depleted signals recovered for some of the large-bodied durophages and the largest of the macrophagous apex predators. Full article

The pasture–animal interface of warm-season perennial grass–legume mixed pastures has never been investigated in forage-based equine systems. Therefore, this 2-year study investigated the herbage and animal responses under 84-day continuous stocking in mixed pastures of rhizoma peanut (RP, Arachis glabrata Benth) and bahiagrass (BG, Paspalum notatum Flüggé) with 30 kg nitrogen (N) ha⁻¹ (BG-RP) compared to BG pastures fertilized with 120 kg N ha⁻¹ (BG-N₁₂₀) and no N (BG-N₀). Measurements were taken every 14 days, except for intake and in vivo digestibility, which were measured every 28 days. BG-N₁₂₀ had the highest stocking rate (p = 0.01; 3.7 AU ha⁻¹) in 2019, while BG-N₀ had the lowest (p = 0.01; 2.6 AU ha⁻¹) in 2020. Crude protein and digestible energy were greatest (p < 0.05) for BG-N₁₂₀ and BG-RP in some of the evaluation days in 2019 but similar across pastures in 2020. Crude protein digestibility was greatest (p < 0.05) for BG-RP in the late season. Intake was less (p = 0.03) for horses grazing BG-RP (3.2%BW) compared to BG-N₀ (5.0%BW). Nonetheless, no differences (p > 0.05) were observed among pastures for body measurements. The results indicate that BG-RP pastures can improve forage nutritive value and maintain horse body condition while maintaining similar stocking rate to monoculture bahiagrass with high N fertilizer rates. Full article

The yak industry constitutes a pivotal segment of livestock development across the Qinghai–Tibetan Plateau and adjacent pastoral regions. Existing studies have shown that supplemental feeding for grazing yaks significantly improves meat quality and growth performance, but its effect on enteric methane (CH₄) emission from yaks has never been reported, so the present experiment aimed to investigate the effect of supplemental feeding of grazing yaks on CH₄ emissions in three different periods of the warm season. Thirty male yaks were randomly assigned to two groups, with 15 yaks per group, The groups were designated as the grazing group (GR), with traditional grazing methods and with an initial body weight of 94.56 ± 3.9 kg, and the supplemental feeding group (GRS) with an initial body weight of 95.01 ± 4.1 kg, which received 1500 g/d of supplemental feed for 120 days. The methane emissions of the two groups were measured at the late regreening period (LRP), the greening-grass period (GGP), and the browning period (BRP) using the SF₆ tracer method. The results showed that GRS increased (p < 0.01) the total DMI during warm season but decreased (p < 0.01) the forage intake at the LRP and GGP, resulting in a significantly reduced methane yield per kg of BW gain and per kg of DMD in warm-season grazing yaks (p < 0.01), a significantly reduced methane production per kg of DMI and methane energy to gross energy ratio in grazing yaks during the GGP (p < 0.05), and a similarly significantly decrease in methane production per kg of DMI and methane energy to gross energy ratio in grazing yaks during the BRP (p < 0.01). In conclusion, supplemental nutrition for grazing yaks during the warm season in alpine grasslands significantly enhances growth performance, reduces methane emissions, and improves dietary energy utilization efficiency. Full article

Forage crops can be grown in mixed species cultivation to provide productivity and nutritional benefits. In a three-round field test, two double-cropping systems (DCSs) based on maize and sorghum as the summer forage crop and alfalfa as the preceding winter forage crop were compared. There were comparisons of harvesting and growing time, nutritive value, as well as biomass and nutritional yields. The superiority of the M–A (alfalfa following a preceding crop of maize) was identified as compared with the S–A (alfalfa following a preceding crop of sorghum). Within the M–A, the maize Dongdan 60 (M1)–alfalfa WL525 (A) combination under the late sowing condition (D3) achieved the highest annual biomass production (fresh weight and dry weight). The maize/alfalfa combination achieved significantly higher nutritional yields compared to those of the sorghum/alfalfa combination. The highest yield of crude protein was obtained in the late sowing (D3) condition for the maize Dongdan 60 (M1)–alfalfa WL525 (A) combination. The highest yield of starch was obtained in the earliest sowing date (D1) in the maize Dongdan 60 (M1)–alfalfa WL525 (A) combination. The highest yield of crude fat was obtained in the latest sowing date (D3) in the maize Dongdan 1331 (M2)–alfalfa WL525 (A) combination. The study indicated that the winter alfalfa and maize DCS could be a promising strategy to achieve high biomass and nutritional productivity. Full article

The study of parasitoid reproductive behaviour is crucial to understanding how parasitoids influence host population dynamics, and the strategies used by parasitoids to maximize their reproductive success. Studying how the parasitoid optimizes its reproductive resources is important as it provides information to improve the efficiency of a biological control programme. Many studies have been carried out on Aphidius ervi to assess the foraging behaviour of the parasitoid, but how the age of the parasitoid affects its foraging behaviour is still poorly understood. In the present study, the influence of the time elapsed between adult parasitoid emergence and the first oviposition in A. ervi was evaluated. Correlations between the parasitoid size and other fitness components were also investigated. Our results show how the parasitoid senescence is associated with the loss of reproductive capacity, as the late field release of parasitoids reduces their total parasitism. We also observed a parasitization rhythm independent of the parasitoid age. Possible explanations for the observed phenomena are discussed. Full article