Food and water intake and selective feeding in rabbits on four feeding regimes

Diet plays an important role in maintaining rabbit health. Feeding an incorrect diet, particularly a low fibre diet, has been linked with digestive, dental and urinary tract disease. However, food intake and dietary requirements have been poorly studied in pet rabbits. This study assessed the effects of two commonly fed pet rabbit diets [extruded nuggets with hay (EH) and muesli with hay (MH)] alongside hay only (HO) and muesli only (MO) on food and water intake in 32 Dutch rabbits. Dry matter (DM) intake was greater in the HO group and lower in the MO group than in the EH and MH groups (p < 0.001). The portion of the diet made of hay was greater in the EH group than in the MH group (p < 0.001). Water intake was positively correlated with DM intake and was greatest in the HO group (p < 0.001). Selective feeding occurred in all rabbit groups fed muesli, whether or not hay was also available. Pellets were rejected, and grains and extrudates selected. The presence of selective feeding in all rabbits fed muesli leads to the consumption of an unbalanced diet. In addition, hay intake and water intake were lower when muesli was fed. Conclusions drawn from this study are based on general recommendations for pet rabbits, and clinical disease may have developed by feeding the study diets over a longer time period, as many diet‐related conditions typically present in older rabbits. However, the study demonstrates that the feeding of muesli diets cannot be recommended.     

Simulating restoration strategies for a southern boreal forest landscape with complex land ownership patterns

Restoring altered forest landscapes toward their ranges of natural variability (RNV) may enhance ecosystem sustainability and resiliency, but such efforts can be hampered by complex land ownership and management patterns. We evaluated restoration potential for southern-boreal forests in the ∼2.1 million ha Border Lakes Region of northern Minnesota (U.S.A.) and Ontario (Canada), where spatially distinct timber harvest and fire suppression histories have differentially altered forest conditions (composition, age–class distribution, and landscape structure) among major management areas, effectively resulting in forest landscape “bifurcation.” We used a forest landscape simulation model to evaluate potential for four hypothetical management and two natural disturbance scenarios to restore forest conditions and reduce bifurcation, including: (1) a current management scenario that simulated timber harvest and fire suppression practices among major landowners; (2) three restoration scenarios that simulated combinations of wildland fire use and cross-boundary timber harvest designed to emulate natural disturbance patterns; (3) a historical natural disturbance scenario that simulated pre-EuroAmerican settlement fire regimes and windthrow; and (4) a contemporary fire regime that simulated fire suppression, but no timber harvest. Forest composition and landscape structure for a 200-year model period were compared among scenarios, among major land management regions within scenarios, and to six RNV benchmarks. The current management scenario met only one RNV benchmark and did not move forest composition, age–class distribution, or landscape structures toward the RNV, and it increased forest landscape bifurcation between primarily timber-managed and wilderness areas. The historical natural disturbance scenario met five RNV benchmarks and the restoration scenarios as many as five, by generally restoring forest composition, age–class distributions, and landscape structures, and reducing bifurcation of forest conditions. The contemporary natural disturbance scenario met only one benchmark and generally created a forest landscape dominated by large patches of late-successional, fire-prone forests. Some forest types (e.g., white and red pine) declined in all scenarios, despite simulated restoration strategies. It may not be possible to achieve all objectives under a single management scenario, and complications, such as fire-risk, may limit strategies. However, our model suggests that timber harvest and fire regimes that emulate natural disturbance patterns can move forest landscapes toward the RNV.     

How many common reptile species are fire specialists? A replicated natural experiment highlights the predictive weakness of a fire succession model

Species with strong preferences for early or late successional stages after fire may be extinction prone under current fire regimes. However, the extent of specialisation to time since fire is poorly understood, and, for reptiles, succession models for predicting responses are in the development phase. In this study we tested predictions of a reptile succession model, and identified species that may be fire specialists. Reptiles were sampled in five burnt and unburnt mallee Eucalyptus woodlands, Australia. Two, 400 m transects within each burn treatment were sampled using 11 pairs of pitfall-traps that were opened for five weeks over two summers. A habitat accommodation model of succession that was previously developed for mallee reptiles correctly predicted the observed responses of three of 16 common reptile species. A further four species showed non-significant trends in the predicted direction. However, eight other species showed unexpected responses. One species showed a strong interaction between burn age and location, requiring a two-dimensional successional model in contrast with the usual linear models explaining reptile responses to fire. One third of common species were not affected by fire and so may not have increased risks of extinction due to the fire suppression/incineration cycle. However, approximately half to two-thirds of common reptiles did have a fire response, so the risk of deterministic extinction in small fragments may be substantial. Further model development is needed to better predict fire responses and to assist the design of fire mosaics that can accommodate early and late successional fire specialists.     

Characteristics of Modern Triticale Quality: The Relationship Between Carbohydrate Properties, α‐Amylase Activity,and Falling Number

Triticale is a high‐yielding cereal crop with potential to increase grain production for human consumption over the coming decades. Minimal targeted selection has been conducted to produce cultivars with α‐amylase, amylose, and nonstarch polysaccharide (NSP) content appropriate for a milling market. Nevertheless, genotypic variability exists. Standard quality screening methods used for wheat, including pasting properties, falling number, and quantification of α‐amylase activity were employed to assess the environmental and genotypic variability among modern triticale cultivars and to investigate the suitability of these tests for triticale. Samples of 11 triticale lines from four environments were compared with five wheat cultivars bred for various end uses. Triticale exhibited a greater range than wheat for most tested variables, and the ranges usually overlapped. Triticale exhibited higher NSP content, generally equivalent pasting properties, higher α‐amylase activity, and lower falling number on average compared with wheat checks. However, low falling number was not indicative of high α‐amylase activity; the relationship with NSP level and other factors is discussed, and caution is recommended for interpretation of previous research. Three cultivars with equivalent α‐amylase activity to wheat and two with partially waxy starch were identified. These findings have great significance for research and the emerging triticale milling market.     

Growth Environment Influences Grain Protein Composition and Dough Functional Properties in Three Australian Wheat Cultivars

The objectives of this study were to assess how functional properties of proteins in whole meal wheat (Triticum aestivum L.) flour vary across different growth environments. Grain from three commercial Australian Hard milling wheat cultivars was analyzed from four growth locations in 2008 and from two of the corresponding cultivars and locations in 2009. The protein content of the grain, soluble and insoluble extractable protein fractions, swelling index of glutenin (SIG), glutenin‐to‐gliadin ratio (Glu:Gli), percent unextractable polymeric protein (%UPP), and dough properties including force at maximum resistance (Rmax) and extensibility were measured. Based on analysis of variance of aggregated data for the cultivars, growth locations, and seasons, growth environment factors made significant contributions to variability in the total grain protein, Glu:Gli ratio, %UPP, SIG, Rmax, and extensibility of the wheat flour. Variability of protein content of the soluble and insoluble extractable protein fractions was mostly owing to genotype.     

Descending efferents from the superior colliculus relay integrated multisensory information

By means of their efferent projections to motor and premotor structures, the cells in the deep superior colliculus are intimately involved in behaviors that control the orientation of the eyes, pinnae, and head. These same efferent cells receive multiple sensory inputs, thereby apparently enabling an animal to orient its receptor organs in response to a wide variety of cues. This sensory convergence also provides a system in which motor responses need not be immutably linked to individual stimuli but can vary in reaction to the multitude of stimuli present in the environment at any given moment.     

Relative ammonia concentrations, dust concentrations, and presence of Salmoneua species and Escherichia coli inside and outside commercial layer facilities

Three air contaminants that may have serious health consequences to humans and poultry are ammonia, dust, and aerosolized bacteria. This study measured ammonia concentrations, dust concentrations, and the presence or absence of aerosolized Salmonella spp. and Escherichia coli inside and outside five commercial layer facilities. The average outside ammonia concentration measurements decreased as the distance from the facility increased from 10 to 40 ft. The measurements at 10 ft from the facilities were consistently higher than the average concentrations inside the facilities. The ammonia measurement trends inside of the facilities were affected by the temperature-dependent ventilation systems. Average dust concentrations inside the five facilities were consistently below 2 mg/m3. Three facilities also experienced average outside dust concentrations at all measured distances below 2 mg/m3. Two facilities had relatively high average dust measurements at 10 ft from ventilation fans (32.12 mg/m3 and 75.18 mg/m3). Escherichia coli and Salmonella were isolated from the air inside all five facilities and outside the facilities up to 40 ft from the ventilation fans. In condusion, dust concentrations may pose the largest risk to human and animal health at 10 ft away from the poultry facilities; risks associated with ammonia inhalation are greatest inside facilities during the coolest months of the year; and aerosolized bacteria are found inside and outside poultry facilities, but further work is needed to quantify the bacteria to further assess the health risk related to this issue.