Food Conversion Efficiency Research Articles

Effect of insect growth regulator, chromafenozide on the food consumption and metabolic efficiencies of the desert locust

The objective of the current investigation was to assess the food deterrence property of chromafenozide and its impact on different food metabolic parameters of the 5th instar nymphs of the desert locust Schistocerca gregaria. For this purpose, three doses (10, 100 and 150 µg/nymph) were topically applied (once) onto the newly molted last (5th) instar nymphs. chromafenozide exhibited contradictory effects on the feeding since it acted as a weak antifeedant against female nymphs only at the lowest dose but acted as phagostimulant against their congeners at the higher two doses. Furthermore, the compound exerted a general phagostimulant action on the male nymphs, regardless the dose. The food intake by the last nymphal instar females was slightly reduced only at only the lowest dose but remarkably increased at the higher doses. The male nymphs had been promoted to consume more food amount. Treated nymphs of both sexes attained slightly or significantly increasing relative weight gain and discharged more frass pellets. The treated nymphs of both sexes achieved slightly increasing approximate digestibility (AD), with two exceptions for the male nymphs which had a slightly decreased AD at the medium dose and un-affected AD at the highest dose. Both the efficiency of conversion of ingested food into biomass (ECI) and efficiency of conversion of digested food into biomass (ECD) of the female nymphs slightly increased. ECI of male nymphs was enhanced but ECD was slightly inhibited. Depending on the present results, Chromafenozide cannot be recommended as a promising agent for controlling S. gregaria.

Nutritional indices and biochemical profile of Helicoverpa armigera [Hübner (1808)] on different groundnut genotypes

Nutritional indices and biochemical profile of Helicoverpa armigera in response to feeding on different groundnut genotypes was studied. The moderately resistant genotypes were ICGV 86699, ICGV 86031, ICG 2271 and ICG 1697. JL 24 was used as the susceptible check. Consumption index (CI), approximate digestibility (AD), efficiency of conversion of ingested food (ECI) and efficiency of conversion of digested food (ECD) were recorded. In addition, the activities of digestive and defensive enzymes of H. armigera were studied. H. armigera larvae showed significantly lower CI, AD, ECI and EDI when fed on moderately resistant genotypes than the insects fed on JL 24. Serine protease and trypsin activities were low in insects fed on resistant genotypes than the ones fed on JL 24. Further, insects fed on resistant genotypes showed significantly greater glutathione-S-transferase activity than the insects fed on JL 24. A reverse trend was observed for esterase activity. Similar trend was observed for total protein content of the insects. Thus, nutritional quality of host plants affects insect’s physiology and could be used as an important indicator of host plant resistance against insect pests and to understand the adaptation of insect pests, if any, to various genotypes/host plants.

Bio-Energetics in Selected Eco-Races of Eri Silkworm

Ericulture is mainly confined to North-Eastern region of India accounting nearly 98% of eri silk produced in the country. Eri silkworm is polyphagous in habit and acclimatized to hardy climatic zones of dry lands. The availability of food plants in various states of the country has opened new vistas for the development of ericulture. An attempt has been made to work out the bio-energetics of selected eco-races of eri silkworm in relation to castor varieties. Total food consumption and digestion differed significantly among the castor hybrid/ variety and eco-races of eri silkworm. Highest total food consumption was registered when Borduar eco-race of eri silkworm was reared on the leaf of DCH-177 hybrid both on fresh and dry weight basis. Further, significantly higher mean consumption index and approximate digestibility were observed when Borduar eco-race of eri silkworm was reared on the leaves of DCH-177 castor hybrid on fresh weight basis, while it was significantly more in DCH-177 × Khanapara on dry weight basis. Mean growth rate was differed statistically between the castor hybrid/ variety and eco-races of eri silkworm and significantly more growth with DCH-177 × Borduar on fresh weight basis and DCH-177 × Mendipathar on dry weight basis.

Uncommon co-infection due to Moniezia expansa and Moniezia benedeni in young goats from Romania: morphological and histopathological analysis.

Digestive parasitoses negatively affect the goat's health, the gain weight of the kids, the efficiency of food conversion, fertility, and productivity, causing important economic losses. This investigation was carried out on a group of goats, Carpathian breed, in the hill area of Tg. Frumos-Iași, to specify the etiology of the acute digestive syndrome, triggered towards the end of the pasturing season, in the young goats. In this context, four sick animals, aged 6-8 months, were slaughtered. Morphological, pathological, and parasitological examination of dissected animals was conducted. Multiple tapeworms belonging to Moniezia expansa and Moniezia benedeni species were found. From the duodenum, jejunum, ileum, fragments were taken for the histopathological processing. The identification of the tapeworm species was carried out through morphological differentiation. The prevalence of tapeworm infection in the examined animals was 100% of which M. expansa was 56.10% and M. benedeni was 43.90%. The average infection intensity was 10.25 tapeworms/animal. The average intensity of infection with M. expansa was 7.5 tapeworms/ animal, and with M. benedeni it was 4.5 tapeworms/animal. Severe pathological lesions in the small intestine such as occlusion, intestinal obstruction, catarrhal inflammation, total atrophy of intestinal villi, ulcerations were produced by the parasites, which led to the clinical expression of the disease and to direct economic losses. The infection with the Moniezia benedeni species is noticed for the first time in Romania, in young goats.

The gill-oxygen limitation theory (GOLT) and its critics.

The gill-oxygen limitation theory (GOLT) provides mechanisms for key aspects of the biology (food conversion efficiency, growth and its response to temperature, the timing of maturation, and others) of water-breathing ectotherms (WBEs). The GOLT's basic tenet is that the surface area of the gills or other respiratory surfaces of WBE cannot, as two-dimensional structures, supply them with sufficient oxygen to keep up with the growth of their three-dimensional bodies. Thus, a lower relative oxygen supply induces sexual maturation, and later a slowing and cessation of growth, along with an increase of physiological processes relying on glycolytic enzymes and a declining role of oxidative enzymes. Because the "dimensional tension" underlying this argument is widely misunderstood, emphasis is given to a detailed refutation of objections to the GOLT. This theory still needs to be put on a solid quantitative basis, which will occur after the misconceptions surrounding it are put to rest.

A high-protein diet containing inulin/oligofructose supports body weight gain associated with lower energy expenditure and carbohydrate oxidation, and alters faecal microbiota in C57BL/6 mice.

Prebiotic supplements and high-protein (HP) diets reduce body weight and modulate intestinal microbiota. Our aim was to elucidate the combined effect of an inulin/oligofructose (FOS) and HP diet on body weight gain, energy metabolism and faecal microbiota. Forty male C57BL/6NCrl mice were fed a control (C) diet for 2 weeks and allocated to a C or HP (40% protein) diet including no or 10% inulin/FOS (C + I and HP + I) for 4 weeks. Inulin/FOS was added in place of starch and cellulose. Body weight, food intake, faecal energy and nitrogen were determined. Indirect calorimetry and faecal microbiota analysis were performed after 3 weeks on diets. Body weight gain of HP-fed mice was 36% lower than HP + I- and C-fed mice (P < 0⋅05). Diet digestibility and food conversion efficiency were higher in HP + I- than HP-fed mice (P < 0⋅01), while food intake was comparable between groups. Total energy expenditure (heat production) was 25% lower in HP + I- than in C-, HP- and C + I-fed mice (P < 0⋅001). Carbohydrate oxidation tended to be 24% higher in HP- than in HP + I-fed mice (P < 0⋅05). Faecal nitrogen excretion was 31-45% lower in C-, C + I- and HP + I- than in HP-fed mice (P < 0⋅05). Faecal Bacteroides-Prevotella DNA was 2⋅3-fold higher in C + I- and HP + I- relative to C-fed mice (P < 0⋅05), but Clostridium leptum DNA abundances was 79% lower in HP + I- than in HP-fed mice (P < 0⋅05). We suggest that the higher conversion efficiency of dietary energy of HP + I but not C + I-fed mice is caused by higher digestibility and lower heat production, resulting in increased body mass.

Effect of Emamectin Benzoate with Leaf Extracts of Parthenium hysterophorus and Moringa oleifera on the Digestibility and Survival Indices of Spodoptera litura (Lepidoptera: Noctuidae)

| Botanical insecticides are an environment-friendly approach and have been used in integrated pest management for various insect pests. Here we tested the effect of emamectin benzoate 1.9% EC alone and with botanicals; Parthenium hysterophorus L. and Moringa oleifera L. on the digestibility indices and survival of Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae). The P. hysterophorus extract at 50 mg concentration was comparable to the alone application of emamectin benzoate in terms of reduced digestibility and survival of S. litura. Overall, 42.7% relative consumption rate (RCR), 74.3% efficiency of conversion of ingested food (ECI), 72.3% efficiency of conversion of digested food (ECD), 87.5% relative growth rate (RGR), 11.04% approximate digestibility (AD), and 47.6% assimilation rate (AR) were reduced after application of a mixture of emamectin benzoate and P. hysterophorus in comparison to control +ve treatment (untreated). The survival rate was also decreased by using this combination compared to the alone application of insecticide. These findings reflect P. hysterophorus extract’s interference with the regulation of feeding and metabolism of S. litura. Further, the results promote P. hysterophorus extract in combination with emamectin benzoate for integrated management of S. litura.

Studies on biological attributes and food utilization efficiency measures of Papilio demoleus on different host plants

During the study period, C. limon was the most suitable among the four hosts viz., Lemon, Citrus limon (L.), Bael, Aegle marmelos (L.), Kinnow, Citrus reticulata Blanco and Kari patta, Murraya koenigii (L.) for this butterfly. The shortest larval development period (13.65 d) was observed on C. limon and significantly, longest period was recorded on M. koenigii (16.62 d) whereas the biggest pupae and adults occurred on C. limon. Murraya koenigii was the least preferred. Rest of the host plants viz., A. marmelos and C. reticulata recorded 15.63 and 14.19 d respectively. During study period approximate digestibility (AD) was higher on C. reticulata (92.08 ± 0.16), (75.0 ± 0.5), (63.38 ± 0.005) during first, third and fourth instar respectively however during second and fifth instar period it was observed higher on C. limon (89.01 ± 0.057) and A. marmelos (66.0 ± 0.5) respectively. Arranged in decreasing order of preference, the four hosts are C. limon, C.reticulata, A. marmelos and M. koenigii. As a general conclusion, both citrus species were suitable hosts for P. demoleus whereby M. koenigii was the least preferred among the four hosts examined.

Differential Feeding Preference and Performance of Leafworm Spodoptera litura Fabricius (Lepidoptera: Noctuidae) on some Cultivars of Potato (Solanum tuberosum L.)

| Leafworm Spodoptera litura Fabricius is a highly polyphagous pest of food, forage, vegetable and horticultural crops. This sporadic species is becoming an emerging threat to the potato crop in central Punjab and is being evidenced infesting potato crop in Sargodha, Faisalabad and Okara districts. This in-vitro study assessed the comparative feeding preference, food consumption and utilization rates and larval development of S. litura on different white and red skinned potato cultivars. Feeding bioassays revealed that all parameters including leaf weight loss, larval weight gain, relative food consumption and growth rates and conversion efficiency of the ingested food were statistically significant (P ≤ 0.05). Exotic potato cultivars Diamant, Desiree and Asterix exhibited maximum leaf consumption and larval weight gain (i.e. 264.61, 259.37 and 233.01 mg and 121.46, 120.17, 120.13 mg, respectively) concomitantly with maximum values of relative growth rate (RGR), relative consumption rate (RCR) and ingested food conversion efficiency (ECI). Cultivars Lady Rosetta, Cardinal, Ajax, Kuroda and Sante exhibited intermediate values. Minimum feeding preference and susceptibility to S. litura was shown by the native potato cultivars Faisalabad Red and Faisalabad White with minimum food consumption, larval weight gain, RGR, RCR and ECI values, and hence are recommended to indigenous potato growers for commercial cultivation in areas where S. litura threatens potato crop.

FOOD CONSUMPTION AND NUTRITIONAL INDICES OF OAK TASAR WORM ANTHERAEA PROYLEI (JOLLY) FED ON QUERCUS GLAUCA

Studies were conducted under laboratory conditions to evaluate the food consumption and nutritional indices for the development of Antheraea proylei larvae fed on Quercus glauca. Larval duration was 5.4±0.489, 6.4±0.48, 7.2±0.4, 9.8±0.74 and 14.2±0.74 days in the 1st, 2nd, 3rd, 4th and 5th instars, respectively. Larvae consumed a total of 28.85 g insect– ¹ day– ¹, egested 4.164 g insect– ¹ day– ¹ and assimilated 24.69 g insect– ¹ day– ¹ of food provided. 82.3% of tissue growth was observed in the 4th and 5th instar larvae. Approximate digestibility (AD) decreased from 91.94% in the first instar larva to 80.79% in the 5th instar larva. Efficiency of conversion of digested food (ECD) into body tissue and efficiency of conversion of ingested food into growth (ECI) increased from 1st instar larva to 5th instar larva. The result obtained in the present study indicate that Q. glauca could serve as an alternate host plant for rearing A. proylei in areas where the main host plant Q. serrata is not found.

Genetic Diversity and Population Structure of Endangered Indian Catfish, Clarias magur as Revealed by mtDNA D-loop Marker

Clarias magur, popularly known as magur, is one of the economically important catfish species having high aquaculture potential in India due to its efficient food conversion, taste, and nutritional benefits. Due to habitat degradation, over exploitation, lack of resources, indiscriminate use of agricultural pesticides and introduction of competitor exotic species, the wild populations are dwindling day by day. According to IUCN, it is listed as endangered species. In the present study, the population genetic structure of 206 magur samples collected from seven different geographical regions was examined using partial mitochondrial D-loop (control region) sequence variation. In total of 17 haplotypes were observed with high number of private alleles, number of haplotypes ranged from 2 to 6 and maximum number of haplotypes was observed in UP population. Haplotype diversity and nucleotide diversity ranged from 0.06897 to 0.76322 and 0.00019 to 0.00208, respectively. Pairwise FST values ranged from 0.01383 to 0.62069 and highest genetic differentiation was observed between AP and AS population. Low genetic diversity and significant population genetic differentiation was observed in the present study. The information generated in the present investigation would facilitate formulating appropriate strategy for management, conservation, and genetic improvement program of this commercially important aquaculture species.

Ecological consequences of Great Lakes salmon subsidies for stream-resident brook and brown trout

Introduced Pacific salmon (Oncorhynchus spp.) deliver novel, pulsed resource subsidies to Great Lakes streams. We explored interactions between native brook trout (Salvelinus fontinalis) and non-native brown trout (Salmo trutta) in the context of this resource pulse. Diets surveyed before and during salmon spawning showed that, regardless of species, trout consumed 4.5-fold more biomass during than before salmon runs. Brook trout grew more quickly than brown trout under controlled feeding regimes due, in part, to their higher food conversion efficiency of 36% compared with 21%. Bioenergetics model simulations explored the influence of temperature on the exploitation of resource pulses and found 35% lower growth rates and increased gorging at colder temperatures. Overall, we found evidence that brook trout and brown trout foraging and growth are modulated by the salmon resource pulse, especially through gorging on eggs. However, these species exhibit distinct physiological adaptations and environmental preferences that may influence their ultimate capacity to exploit resource pulses. The effects of environmental conditions and salmon subsidies on stream-resident trout have broader consequences for fisheries management and conservation efforts.

Innovative biorefinery concept for biogas-based digestate with rice bran protein-rich feed ingredient for tilapia production

This study evaluated the nutritional value and amino acid profiles of digestate from a biogas plant, as a substitute for rice bran, in tilapia feed and measured its effects on fish yields and production costs. Four isonitrogenous (24% crude protein) diets were formulated, using digestate at levels of 0%, 10%, 20%, and 30%, with respective reductions in rice bran content (31%, 24%, 17%, and 9%). The experiment was a triplicated, completely randomized design (CRD), starting with 140 fish fry per cage (3.0 × 3.0 × 2.0 m). The fish were fed to satiation twice per day for 180 days. Digestate was more nutritious than rice bran, with 15.3% crude protein and exceptionally high lysine (1872 mg/100 g). Differences in the diets tested had no significant effects on fish survival rates, growth and yield, and food conversion efficiency. The present findings strongly suggest that farmers could adopt tilapia growing systems with cheap and increase aquaculture production in order to meet the fish protein need and food security. Consequently, the least expensive diet was the most cost-effective.

Juvenile Greenland halibut (Reinhardtius hippoglossoides) growth in the context of rising temperature in the Estuary and Gulf of St. Lawrence

In a context of climate change, understanding the influence of temperature on fish species growth is important for the management of fisheries. The effect of increasing temperature on the growth of juvenile Greenland halibut (Reinhardtius hippoglossoides), a cold-water species, circum-continental in the Arctic, was investigated on juveniles that had been captured in the wild and kept in captivity. Mortality rate increased with higher temperature, from 4.5 % at 4.0 °C to 15.2 % at 7.5 °C. Relative growth (normalized in degree-days) was lower at 7.5 °C than at the two other temperatures tested. Food conversion efficiency, muscle energy content, and the Fulton condition index were not influenced by temperature, but food intake significantly increased over time at 5.5 °C. No clear difference in growth trajectories between sexes was highlighted. Overall, the results suggest that optimal temperature conditions were exceeded at 7.5 °C and that any further increase in temperature would significantly decrease survival and impair juvenile growth. With the current deep-water warming trends in the Estuary and Gulf of St. Lawrence, recruitment and commercial fishing of Greenland halibut may be impaired in the near future.

Effect of feed supplementation with Origanum vulgare L. essential oil on sea bass (Dicentrarchus labrax): A preliminary framework on metabolic status and growth performances

This study provided a preliminary framework for the effects of Origanum vulgare L. essential oil (EO) on sea bass (Dicentrarchus labrax) health status over a 60-day feeding trial. Fish were fed twice a day until apparent satiety with three different diets: a control diet (CD), and two experimental diets supplemented with 100 (D100) and 200 (D200) ppm of oregano EO. No mortality was observed in each treatment. Feeding on D100 diet resulted in high growth performances and better food conversion and protein efficiency ratios. Additionally, the supplementation of 100 ppm EO diet also improved (P < 0.05) hepatosomatic and viscerosomatic indices, compared both to control and D200 diets. EO feeding positively affected (P < 0.05) several serum biochemical indices (amylase activity and total proteins, glucose, triglycerides, and cholesterol levels). Focusing on the antioxidant potential of blood, D100 led to the highest (P < 0.05) ferric reducing antioxidant power values and the lowest (P < 0.05) thiobarbituric acid-reactive substances levels in blood.

The Effect of Morus Leaf Quality on Bombyx mori L. Nutrition Index

The effect of quality mulberry leaf Morus cathayana on nutrition index of silkworm Bombyx mori L. have been conducted . This research was Completely Randomized Design (CRD) by two treatments. The first treatment was mulberry plant that cultivated on soil with Urea, TSP and NPK fertilizers and the second was the plants were not fertilized l. Each treatment was replicate 20 times. The results showed that the addition of Urea, TSP and NPK fertilizer on mulberry has effect (p&lt;0,05) on increasing of the growth rate (GR) of instar III, the consumption rate (CR) of instars III and V, and efficiency of conversion of ingested food (ECI) of instar III and V. In addition, approximate digestibility (AD) of instar III, IV were 20%, 7%, 24%, 40% and then V was 51%, 15%, 21% and 70% respectively.

The EFFECT OF THE QUALITY OF Morus cathayana LEAVES AGAINST NUTRITION INDEX Bombyx mori L.

The effect of quality mulberry leaf Morus cathayana on nutrition index of silkworm Bombyx mori L. have been conducted . This research was Completely Randomized Design (CRD) by two treatments. The first treatment was mulberry plant that cultivated on soil with Urea, TSP and NPK fertilizers and the second was the plants were not fertilized l. Each treatment was replicate 20 times. The results showed that the addition of Urea, TSP and NPK fertilizer on mulberry has effect (p&lt;0,05) on increasing of the growth rate (GR) of instar III, the consumption rate (CR) of instars III and V, and efficiency of conversion of ingested food (ECI) of instar III and V. In addition, approximate digestibility (AD) of instar III, IV were 20%, 7%, 24%, 40% and then V was 51%, 15%, 21% and 70% respectively.

Some Plant Essential Oils Induce variations in the Physiological Aspects and Midgut Ultrastructure of Larvae of Spodoptera littoralis (Lepidoptera: Noctuidae)

In the present study, the variations in the nutritional physiology and midgut ultrastructure of fourth-instar larvae of the Egyptian cotton leafworm, Spodoptera littoralis, treated with the essential oils of garlic (Allium sativum) and lemon (Citrus limon), were compared to those of control larvae. The food consumption index, relative growth rate and approximate digestibility of the treated larvae were significantly decreased. In contrast, the efficiency of conversion of both ingested and digested food to body mass was significantly increased. The midgut ultrastructural variations included vacuolisation of the columnar cells, clumping of the nuclear chromatin, disorder of microvilli, loss of cytoplasmic projections of the goblet cells, disorganisation of mitochondria and appearance of residual bodies. It seems likely that mitochondria are the target site of garlic and lemon essential oils. The overall results suggest that the essential oils of garlic and lemon under investigation interfere with the nutritional physiology and ultrastructure of the midgut of S. littoralis larvae and have potential for their control. Future studies will be undertaken to evaluate the efficacy of garlic and lemon oils under field conditions.

Functional traits of individual varieties as determinants of growth and nitrogen use patterns in mixed stands of willow (Salix spp.)

Short rotation plantations of willows (Salix spp.) have high biomass production potential in many parts of the world, and may frequently support ecosystem services related to nutrient cycling. A plantation management enhancing favorable environmental impacts that are conducive to maintaining ecosystem services is a main challenge in establishing sustainable biomass production systems. There is evidence supporting the hypothesis that biomass production and nutrient cycling can be increased by supporting ecosystem niche differentiation (complementarity) through enhancing the number of plant species or varieties grown in the stand. However, the specific trait values of the individual components (e.g., varieties) in a mixed community could also be more important than the community diversity per se. We assessed, at community level, the plant trait profiles related to growth and nitrogen (N) use for four different Salix varieties that were taxonomically distinct at species or genotype level (‘Björn’, ‘Jorr’, ‘Loden’, ‘Tora’) and field-grown in unfertilized plots of pure and mixed communities during one cutting cycle in Central Sweden. The aims were to use elements of functional growth analysis for exploring the mechanistic relationships between various traits related to growth and N use at stand level in our pure and mixed willow communities; and to address two hypotheses related to (i) the effect of diversity level on above-ground traits linked to growth, N uptake efficiency, N productivity and N conservation; and (ii) the influence of individual variety identities on the growth and N use traits observed in a mixture. Diversity level had no significant effect on the traits assessed here, and we thus found no evidence in support of our hypothesis that traits linked to growth, N uptake and use are significantly affected by the diversity level per se. In most but not all cases, the admixing effects on trait values were explained by the effects of the individual variety characteristics assessed in monocultures in combination with their relative share in the respective mixtures. The absence or presence of individual varieties strongly affected community-averaged (stand level) trait values. Therefore, the design of desirable variety mixtures is suggested that combine, for example, the high nutrient conversion efficiency that certain varieties achieve in mixed stands with the specific nutrient acquisition characteristics of other varieties.

Efficacy of Mulberry Varieties on Young Instars Larvae of Silkworm, Bombyx mori L.

Six mulberry varieties were selected for feeding young silkworm, Bombyx mori L. These varieties were Morus alba Linn. Var. Iljiros (A), Morus Ihou Koidz. Var. Josaengrok (B), Morus alba Linn. Var. Kearyang-Seoban (C), Morus Ihou Koidz. Var. Nosang (D), Morus alba Linn. Var. Afiluniz (E) and Morus alba Linn. Var. Kokuso-27(G). During the 4th and 5th larvae instar of silkworm instar, nutritional were tested, data were collected on the biomass of larvae and cocoons for 6 treatments on ingesta, digesta, excreta, approximate digestibility (AD), reference ratio (RR), consumption index (CI), relative growth rate (RGR), respiration (R) and metabolic rate (MR), efficiency conversion of ingesta (ECI) and digesta (ECD) for larva, cocoon, and shell. Further, the ingesta and digesta required for producing one gram of cocoon and shell (I/g and D/g). Characters of young instars duration (YID), fifth duration (FID), total larval period (TLD), cocooning percentage (CP), pupation ratio (PR), sex ratio (SR), number of cocoons/liter (C/L), fresh cocoon weight (FCW), fresh cocoon shell weight (FCSW), fresh pupa weight (FPW), fresh cocoon shell ratio (FCSR) and silk productivity (SP) for female and male. In addition to length of silk filament (FL), weight of silk filament (FW), size of reeled thread (denier; FS) and silk ratio (SR) were investigated.