A prediction equation for enteric methane emission from dairy cows for use in NorFor

Abstract

A data-set with 47 treatment means (N = 211) was compiled from research institutions in Denmark, Norway, and Sweden in order to develop a prediction equation for enteric methane (CH₄) emissions from dairy cows. The aim was to implement the equation in the Nordic feed evaluation system NorFor. The equation should therefore be based on input variables available in NorFor. The best equation to predict CH₄ (MJ/d) was based on dry matter intake (DMI, kg/d), and content of (g/kg DM) fatty acids (FA), crude protein (CP), and neutral detergent fiber (NDF). The equation was CH₄ = 1.36 (±0.10) × DMI – 0.125 (±0.039) × FA – 0.02 (±0.012) × CP + 0.017 (±0.005) × NDF (RMSE = 3.00 MJ CH₄/d; CV = 13.8%; R² = 0.77), where RMSE is the root mean square error and CV is the coefficient of variation. However, CP was on the borderline of being significant and did not quantitatively explain much variation in CH₄ emission. Based on the present research, we concluded, therefore, that the equation CH₄ = 1.23 (±0.08) × DMI – 0.145 (±0.039) × FA + 0.012 (±0.005) × NDF (RMSE = 3.10 MJ CH₄/d; CV = 14.3%; R² = 0.75) is most suited for being implemented in NorFor. However, the ability of the proposed equation to predict enteric methane emissions is uncertain until evaluated on an independent data-set.     

Species formation through punctuated gradualism in planktonic foraminifera

Detailed analysis of evolutionary changes in a 10-million-year long Late Neogene lineage of planktonic foraminifera has revealed a pattern that is not consistent with either the gradualistic or the punctuational model of evolution. The lineage was in stasis over a considerable part of its total duration but underwent relatively rapid, but not geologically instantaneous, gradual morphologic change that did not lead to lineage splitting. The term punctuated gradualism is suggested for this evolutionary modality.     

The solubility of aluminium in two Swedish acidified forest soils: An evaluation of lysimeter measurements using batch titration data

This paper presents aluminium (Al)-solubility data for two acid forest soils (Inceptisol and Spodosol), obtained in connection with lysimeter measurements (tension-cup and zero-tension lysimeters) and batch equilibrium experiments. The solubility of Al obtained in the batch experiments was used as a reference to test whether Al³⁺in soil solutions collected by the lysimeters was in equilibrium with secondary forms of solid-phase Al (Al(OH)₃or organically bound Al). The relation between pH and Al³⁺activity found for the zero-tension lysimeter solutions collected from the Inceptisol agreed well with that obtained in the batch experiment. This suggests that Al³⁺in the lysimeter solutions were in, or close to, equilibrium with the solid phase, whether this was organically bound Al (A horizon) or an Al(OH)₃phase (B horizon). For the tension-cup lysimeters, solutions obtained from the Inceptisol B and Spodosol Bs1 horizons were generally close to equilibrium with respect to secondary solid-phase Al (apparently Al(OH)₃; average ion activity product was 10^9.3and 10^8.8, respectively), whereas the Inceptisol A and Spodosol Bh solutions were not. The Al solubility in Inceptisol A and Spodosol Bh horizons was consistently higher than that obtained in the batch equilibrium experiment, indicating that the sampled solution partly originated from the underlying horizons. Thus, tension-cup lysimeters should be used with care in soils (or in parts of soil profiles) having steep solute concentration gradients because the soil volume from which the sample is drawn with this lysimeter type seems to be poorly defined.     

Tank size and fish management history matters in experimental design

To investigate the questions: (1) does tank size affect fish performance; (2) does tank size prior to an experiment affect later fish performance and (3) how does performance in experimental tanks compare with rearing in industry‐scale cages, Atlantic salmon smolts were acclimatized to 190, 3 or 0.9 m³ tanks (Phase 1; 1.5 months) before redistributed to Phase 2 for 5 months. Question 1: fish in 190 m³ tank were redistributed to 0.9 m³ (190 m³ → 0.9 m³), 3 m³ (190 m³ → 3 m³), or 103 m³ (190 m³ → 103 m³) tanks. Question 2: fish in 0.9 m³ tanks were redistributed to 3 m³ tanks (0.9 m³ → 3 m³), and compared to fish from 190 m³ tank (190 m³ → 3 m³). Question 3: fish were placed directly in 3 m³ tanks, not moved (3 m³ → 3 m³), and compared to reference sea cages. Phase 2 mortality: 190 m³ → 0.9 m³ (46%), 190 m³ → 3 m³ (29%), 190 m³ → 103 m³ (19%), 3 m³ → 3 m³ and 0.9 m³ → 3 m³ (<5%). Most mortality happened shortly after transfer. Our study suggests tank size dependent performance, based on growth and feed intake that increased with tank size. 190 m³ → 103 m³ fish were more active than 190 m³ → 0.9 m³ and 190 m³ → 3 m³ fish. 190 m³ → 103 m³ tanks had lowest relative variance. Previous tank scale history affected survival, since 0.9 m³ → 3 m³ fish showed higher survival than 190 m³ → 3 m³ fish. However, previous scale history did not affect growth rate, feed intake or somatic indexes. Fish performance in 3 m³ → 3 m³ tanks did not differ from the reference sea cages. However, fish in 103 m³ tanks performed better than reference cages, suggesting potential for improved commercial production. This study demonstrates that management practices can influence fish performance and should be taken into account when designing experiments.     

Bursatella leachii from Mar Menor as a Source of Bioactive Molecules: Preliminary Evaluation of the Nutritional Profile,In Vitro Biological Activities,and Fatty Acids Contents

Marine invertebrates contain nutritionally important elements that make them suitable to be included in the human diet, and they are considered an outstanding source of secondary metabolites with multiple biotechnological uses. The sea hare Bursatella leachii is an invasive species in Mar Menor that can be managed through the control of its reproduction and/or by massive biomass removal. In this context, this work evaluated the possible use of biomass from B. leachii in the food and cosmetics industries. Biomass was appraised for nutritional properties, and extracts were prepared and evaluated in vitro for antioxidant and anti-inflammatory capacity, cholinesterase and tyrosinase inhibition, and for total contents in different phenolic groups. It had a moderate moisture level, low ash and fat levels, and an adequate protein amount and protein/lipid ratio. The fatty acids (FA) profile was mainly saturated, dominated by palmitic acid. The methanol extract had the highest acetylcholinesterase inhibition. The acetone extract had the strongest capacity to scavenge 1,1-diphenyl-2 picrylhydrazyl (DPPH) radical, reduce iron, inhibit tyrosinase, decrease nitric oxide production in lipopolysaccharide (LPS)-stimulated microglia cells, and the upmost levels of total phenolics, flavonoids, and tannins. Our results suggest multiple biotechnological applications for B. leachii biomass in different economic areas.     

Lack of essential fatty acids in live feed during larval and post-larval rearing: effect on the performance of juvenile <Emphasis Type="Italic">Solea senegalensis</Emphasis>

Despite the large progress obtained in recent years, Senegalese sole (Solea senegalensis) production of high quality juveniles is still a bottleneck. This paper examines the effect of larval and post-larval lipid nutrition on juvenile performance and quality. Four dietary treatments were tested: A—enriched Artemia spp. (EA); B—non-enriched Artemia spp. (NEA); C—EA during the pelagic larval period and NEA after larval settlement; D—50% EA and 50% NEA. Juvenile fatty acid profile at 60 days after hatching (DAH) clearly reflected the larval and post-larval diet composition. Feeding sole larvae on NEA (poor in lipids and essential fatty acids-EFA) had a negative effect, reducing growth (total length and dry weight) after 30 DAH and decreasing digestive enzyme activity at the end of the rearing period (60 DAH). However, relatively good performance compared to the EFA-richest treatment (A) was obtained when larvae were fed 50% EA and 50% NEA (D) or even EA only during the pelagic larval period followed by NEA after larval settlement (C). Malpigmentation was not affected by the dietary regimes and its incidence was very low. However, skeletal deformities were prevalent, particularly in the caudal complex, independently of diet. The results confirm that Senegalese sole appear to have lower larval EFA requirements than most cultured marine species and potentially even lower requirements during the post-larval stage. The importance of studying the impact of early nutrition on later juvenile stages was clearly highlighted in this study.     

Nutritional responses in rainbow trout (Oncorhynchus mykiss) fed diets with different physical qualities at stable or variable environmental conditions

Rainbow trout with initial body weight 1144 g were fed two diets with high (feed A) or low (feed B) water stability for 6 weeks. During the last 2 weeks either stable or fluctuating oxygen saturation, salinity and temperature was introduced. High water stability of the feed was associated with harder pellets, less dust formation and less broken pellets compared to feed with low water stability. During the first 4 weeks, feed intake was 23% higher in trout fed diet B than in those fed diet A. Fluctuating environment resulted in a severe drop in feed intake for both dietary groups. At termination of the trial, stomachs of trout fed feed B contained mashed pellets and free water and oil. Stomachs of trout fed feed A contained more intact pellets and little fluid. The apparent digestibility of protein, starch, dry matter and energy was highest in feed A. The apparent digestibility of P and Zn was highest at stable environment, and the absorption of P was highest from feed A. In conclusion, physical quality affected the nutritional value of the feeds, and differences in nutritional value at stable or fluctuating environment appeared to be related to feed intake.