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Aims Human land use such as agriculture and logging can have cascading effects on the environment and severely influence forest ecosystems by altering structure, species composition and community processes. These activities may have long-term consequences, which impact forest recovery. We investigated the legacy of historical anthropogenic land use on the current reproductive effort (RE) and success of the understory, myco-heterotrophic orchid, Wullschlaegelia calcarata in Puerto Rico's tropical rain forest after 80 years of forest recovery. Methods Our study site was the 16-ha Luquillo Forest Dynamics Plot in the Luquillo Experimental Forest. We used six 10 m × 500 m transect lines that spanned areas with differing levels of historic canopy coverage which are correlated with land use history. We recorded the abundance of W. calcarata plants and measured shoot height, number of flowers, fruit set for all plants and seed set from the most mature, undehisced fruit on a random subset of plants measured. We sought to determine whether or not there is a legacy of land use history on the RE and success of W. calcarata. Of the varying degrees of historic disturbance, we predicted that RE and success would be highest in minimally disturbed old-growth forest, and that soil type differences would be insufficient to affect RE or success. Important Findings We found 1607 plants of W. calcarata, and only one was detected in the most historically disturbed area of the forest. The orchids were most abundant in the two least historically disturbed sites. However, the prevailing trend in all measures of RE is in the opposite direction with greater RE in the forest plots with intermediate levels of historical disturbance. Furthermore, the best model (as a function of AICc and weights) to predict RE is a combination of soil type and cover class. Nevertheless, our measures of reproductive success (fruit and seed set) were best in the least historically disturbed sites and were not associated with soil type. Thus, the best sites for growth are not always the same as those for abundance and reproduction, and after >80 years of recovery, components of the rainforest community have not fully recovered. [ABSTRACT FROM AUTHOR]

This study compared the in‐vat moisture loss kinetics under fixed cheesemaking conditions during 75 min of stirring of curds prepared from protein‐standardised milks produced from indoor cows fed total mixed ration (TMR), or outdoor cows fed grass only (GRA) or grass mixed with clover (CLO). Relative curd moisture as a function of time was fitted to different empirical equations, of which a logarithmic function gave the best fit to the experimental data. The moisture loss rate constant (k/min) was found to be similar for curds from protein‐standardised TMR, CLO and GRA milks, showing minimal feed‐induced variations in syneresis. [ABSTRACT FROM AUTHOR]

Hawaiian lowland wet forests (HLWF) have been subject to degradation as a result of human activities and the introduction of non-native plant and animal species. Arthropods play crucial roles in forest ecological processes and food web dynamics, and this study aims to compare arthropod diversity and herbivory in HLWF with high or low degrees of invasion. The objective of this study is to test whether invaded HLWF have greater arthropod diversity and therefore higher rates of herbivory than HLWF undisturbed by invasion. In addition, it is hypothesized that invasive plants have higher levels of herbivory due to their pioneer traits, which involve fast growth and low defense physiology. We set up two types of arthropod traps, and herbivory and leaf traits of two native and two non-native plants were assessed at both forest sites. Contrary to our hypotheses, we observed a higher variety of arthropods and higher levels of herbivory at the primarily native site. Primarily native forests may provide more fitting environments for arthropods than invaded forests. [ABSTRACT FROM AUTHOR]

This study evaluated the effects of 3 widely practiced cow feeding systems in the United States, Europe, and Southern Hemisphere regions on the characteristics, quality, and consumer perception of sweet cream butter. Fifty-four multiparous and primiparous Friesian cows were divided into 3 groups (n = 18) for an entire lactation. Group 1 was housed indoors and fed a total mixed ration diet (TMR) of grass silage, maize silage, and concentrates; group 2 was maintained outdoors on perennial ryegrass-only pasture (GRS); and group 3 was maintained outdoors on a perennial ryegrass/white clover pasture (CLV). Mid-lactation butter was manufactured in triplicate with milk from each group in June 2015 (137 ± 7 d in milk) and was analyzed over a 6-mo storage period at 5°C for textural and thermal properties, fatty acid composition, sensory properties, and volatile compounds. The nutritional value of butters was improved by pasture feeding, and butter from pasture-fed cows had significantly lower thrombogenicity index scores compared with butters from TMR-fed cows. In line with these results, pasture-derived milks (GRS and CLV) produced butter with significantly higher concentrations of conjugated linoleic acid (cis-9,trans-11) and trans-β-carotene than TMR butter. Alterations in the fatty acid composition of butter contributed to significant differences in textural and thermal properties of the butters. Total mixed ration-derived butters had significantly higher hardness scores at room temperature than those of GRS and CLV. Onset of crystallization for TMR butters also occurred at significantly higher temperatures compared with pasture butters. Volatile analysis of butter by gas chromatography-mass spectrometry identified 25 compounds present in each of the butters, 5 of which differed significantly based on feeding system, including acetone, 2-butanone, 1-pentenol, toluene, and β-pinene. Toluene was very significantly correlated with pasturederived butter. Sensory analysis revealed significantly higher scores for GRS-derived butter in several attributes including "liking" of appearance, flavor, and color over those of TMR butter. Partial least square regression plots of fatty acid profiles showed clear separation of butter derived from grazed pasture-based perennial ryegrass or perennial rye/white clover diets from that of a TMR system, offering further insight into the ability of fatty acid profiling to verify such pasture-derived dairy products. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of different feeding systems on milk quality and composition. Fifty-four multiparous and primiparous Friesian lactating cows were divided into 3 groups (n = 18) to study the effects of 3 feeding systems over a full lactation. Group 1 was housed indoors and offered a total mixed ration diet (TMR), group 2 was maintained outdoors on a perennial ryegrass pasture (referred to as grass), and group 3 was also grazed outdoors on a perennial ryegrass/white clover pasture (referred to as clover). Bulk milk samples were collected from each group at morning and afternoon milkings once weekly from March 11 to October 28 in 2015. Milk from pasture- fed cows (grass and clover) had significantly higher concentrations of fat, protein, true protein, and casein. The pasture feeding systems induced significantly higher concentrations of saturated fatty acids C11:0, C13:0, C15:0, C17:0, C23:0, and unsaturated fatty acids C18:2n-6 trans, C18:3n-3, C20:1, and C20:4n-6 and a greater than 2-fold increase in the conjugated linoleic acid C18:2 cis-9,trans-11 content of milk compared with that of the TMR feeding system. The TMR feeding system resulted in milks with increased concentrations of C16:0, C18:2n-6 cis, C18:3n-6 cis, C22:0 C22:1n-9, and C18:2 cis-10,trans-12. Principal component analysis of average fatty acid profiles showed clear separation of milks from the grazed pasture-based diets to that of a TMR system throughout lactation, offering further insight into the ability to verify pasture-derived milk by fatty acid profiling. [ABSTRACT FROM AUTHOR]

The purpose of this study was to examine the effects of two pasture feeding systems-perennial ryegrass (GRS) and perennial ryegrass and white clover (CLV)-and an indoor total mixed ration (TMR) system on the (a) rumen microbiome; (b) rumen fluid and milk metabolome; and (c) to assess the potential to distinguish milk from different feeding systems by their respective metabolomes. Rumen fluid was collected from nine rumen cannulated cows under the different feeding systems in early, mid and late lactation, and raw milk samples were collected from ten non-cannulated cows in mid-lactation from each of the feeding systems. The microbiota present in rumen liquid and solid portions were analysed using 16S rRNA gene sequencing, while ¹H-NMR untargeted metabolomic analysis was performed on rumen fluid and raw milk samples. The rumen microbiota composition was not found to be significantly altered by any feeding system in this study, likely as a result of a shortened adaptation period (two weeks' exposure time). In contrast, feeding system had a significant effect on both the rumen and milk metabolome. Increased concentrations of volatile fatty acids including acetic acid, an important source of energy for the cow, were detected in the rumen of TMR and CLV-fed cows. Pasture feeding resulted in significantly higher concentrations of isoacids in the rumen. The ruminal fluids of both CLV and GRS-fed cows were found to have increased concentrations of p -cresol, a product of microbiome metabolism. CLV feeding resulted in increased rumen concentrations of formate, a substrate compound for methanogenesis. The TMR feeding resulted in significantly higher rumen choline content, which contributes to animal health and milk production, and succinate, a product of carbohydrate metabolism. Milk and rumen-fluids were shown to have varying levels of dimethyl sulfone in each feeding system, which was found to be an important compound for distinguishing between the diets. CLV feeding resulted in increased concentrations of milk urea. Milk from pasture-based feeding systems was shown to have significantly higher concentrations of hippuric acid, a potential biomarker of pasture-derived milk. This study has demonstrated that ¹H-NMR metabolomics coupled with multivariate analysis is capable of distinguishing both rumen-fluid and milk derived from cows on different feeding systems, specifically between indoor TMR and pasture-based diets used in this study., Competing Interests: The authors declare no conflict of interest.