The widespread adoption of genetically modified, glyphosate-tolerant corn and soybean varieties in US crop production has led to a dramatic increase in glyphosate usage. Though present at or below regulatory limits currently set for human foodstuffs, the concentration of glyphosate in companion animal feed is currently unknown. In the present study, 18 commercial companion animal feeds from eight manufacturers were analyzed for glyphosate residues using ELISA. Every product contained detectable glyphosate residues in the range of 7.83 × 10¹–2.14 × 10³ μg kg⁻¹ dry weight, with the average and medians being 3.57 × 10² and 1.98 × 10² μg kg⁻¹ respectively. Three products were tested for within-bag variation and six were tested for lot to lot variation. Little within-bag variation was found, but the concentration of glyphosate varied by lot in half of the products tested. Glyphosate concentration was significantly correlated with crude fiber content, but not crude fat or crude protein. Average daily intakes by animals consuming feeds containing the median glyphosate concentration are estimated to result in exposures that are 0.68–2.5% of the Allowable Daily Intake (ADI) for humans in the US and EU, which are 1750 and 500 μg kg⁻¹ respectively. Consumption of the most contaminated feed, however, would result in exposure to 7.3% and 25% of the above ADIs, though the relevance of such an exposure to companion animals is currently unknown.Companion animal feeds contained 7.83 × 10¹–2.14 × 10³ μg kg⁻¹ glyphosate which is likely to result in pet exposure that is 4–12 times higher than that of humans on a per Kg basis.

A mixture of common Southern Piedmont (USA) grassland species (Lolium arundinacea, Paspalum dilatatum, Cynodon dactylon and Trifolium repens) was exposed to O₃ [ambient (non-filtered; NF) and twice-ambient (2X) concentrations] and fed to individually caged New Zealand white rabbits (Oryctolagus cuniculus) in a digestibility experiment. Forages and feed refusals were analyzed for concentrations of total cell wall constituents, lignin, crude protein, and soluble and hydrolyzable phenolic fractions. Neutral detergent fiber and acid detergent fiber digestibility by rabbits were significantly lower for 2X than NF forage. Decreased digestibility could not be attributed to lignin concentrations, but was associated with increased concentrations of acid-hydrolyzable and saponifiable phenolics. Exposure of forage to elevated O₃ resulted in decreased digestible dry matter intake by rabbits. Elevated O₃ concentrations could be expected to have a negative impact on forage quality, resulting in decreased nutrient utilization by mammalian herbivores in Southern Piedmont grasslands under projected future climate scenarios.

In this study, the bioremediation potentials of two seaweeds (Sargassum hemiphyllum and S. henslowianum) against pollution in a coastal mariculture area of Shenzhen, South China, were investigated by comparing the growth, nutrient bioaccumulation capacity of plants from the seaweed bed (control site) with plants from the fish farm. Results indicated that both species are potential candidates for bioremediation in the fish farm areas in terms of their high growth rates and high bioaccumulation capacities on inorganic nutrients. Both Sargassum spp. contain high levels of crude protein (11.7–14.0%) and crude fat (2.2–2.7%), suggesting high nutritional values. The S. hemiphyllum may serve as a good aquaculture fodder with high nutritional compositions and low heavy metal contents. However, heavy metals (Cr, Pb and Cd) of S. henslowianum exceed the maximum allowable concentrations as aquatic feed, which restricts its fodder application. In general, the results of this study may contribute to the marine pollution bioremediation in the coastal areas of South China, especially in mariculture zones.

This study aimed at the evaluation of the mitigating effects of dietary zeolites (ZEO) and/or chitosan nanoparticle (ChNP) on imidacloprid (IMID)-induced toxicity in Nile tilapia (Oreochromis niloticus). Fish (18.03 ± 0.01 g) were allocated into six groups; one fed on a basal diet (control) (CTR), and the other groups were fed diets supplemented with ChNPs (5 g kg⁻¹) and/or ZEO (20 and 40 g kg⁻¹) (ZEO₂₀ and ZEO₄₀) for 60 days. In the last 14 days of the experiment, all groups were exposed to a sub-lethal dose of IMID (½ of 96 h LC₅₀ = 0.0545 μg L⁻¹). Dietary ZEO₂₀ significantly improved all growth parameters (P ˂ 0.05), while ChNPs had no significant effects. The crude protein of the fish body was significantly increased in all groups compared to the CTR (P ˂ 0.05). No significant impacts of ChNPs, ZEO, and their interaction (P > 0.05) were noticed on the moisture, dry matter, and ash percentages. Compared to the CTR, hematocrit values were significantly decreased (P ˂ 0.05) in ChNP and ZEO₂₀ groups; meanwhile, their levels were significantly increased (P ˂ 0.05) in the ZEO₄₀ group and all combined treatments. Fish fed diets with ChNPs and/or ZEO had significant increments in the MCV values (P ˂ 0.05). Moreover, fish fed diets supplemented with ChNPs or their combination with ZEO had the lowest glucose and alkaline phosphatase levels compared with the CTR. Serum aspartate transferase levels were significantly decreased in all treated groups (P ˂ 0.05) compared to the CTR. ChNPs alone or combined with ZEO significantly exhibited the highest lysozyme and nitro blue tetrazolium values (P ˂ 0.05). On the other hand, fish in the CTR group had the highest malondialdehyde and lowest nitric oxide levels compared to the other groups. Interestingly, the lowest IMID residues in fish flesh were found in fish groups fed diet with a combination of ZEO and ChNPs. Partial or complete protection of the hepatic and splenic tissues were observed in fish group with combined treatment with ChNPs and ZEO. In conclusion, the application of ZEO and/or ChNPs in Nile tilapia diets looks to be a leading approach to mitigate the toxic impacts of IMID.

The natural grasslands in northern China have been seriously degraded due mainly to overgrazing and climate change in recent decades, leading to shortage of forage supply to animal husbandry. To maximize forage production, we developed a two-harvest regime of oat forage by sowing in spring in an alpine region of Hulun Buir, northern China, using two oat early maturation species. The agronomic characteristics and forage quality of the two-harvest regime were evaluated across three constructive years from 2017 to 2019. Compared to the traditional one-harvest regime, the production, resource use efficiency, and economic benefits were compared and quantified for both oat species across the 3 years. Dry weight forage by the two-harvest regime was increased by 17.5–18.5%, while crude protein was increased by 25.1–30.0%. Growing days by the two-harvest regime was increased by 36.7% on average, nitrogen fertilizer use efficiency was enhanced by 25.1–30.0%, while water use efficiency was not significantly changed. The two-harvest regime also increased the net profit by 28.0%. Taken together, our results reveal that the two-harvest regime of forage production in the cold region of northern China is a promising practice with high forage yield, nutritional value, and nitrogen fertilizer use efficiency as well as economic profit.

In this study, a mixed-level orthogonal array design was employed for the optimum conditions of breeding housefly larvae by food waste. The results showed that the effects of these factors on the weight of 50 larvae, larvae yield, and crude protein content were the culture substrate ratio > the breeding density > the feeding mode. The optimum conditions for the housefly larvae to convert food waste were as follows: culture substrates ratio 1:3, breeding density 10.0 g/kg, and all substance added on the first day. The optimum food waste mass reduction rate was 79.1–83.6%. The value of the essential amino acids (Eaa)/ the total amino acids (Taa) (45.1%) and E/the nonessential amino acid (Naa) values (0.83%) in the housefly larvae products met the Food and Agricultural Organization (FAO) requirements for feed protein. The crude fat content (30.1 ± 1.18%) was higher than of the housefly larvae after bioconversion of pig manure (22.0%) and the fish meal standard of China. The contents of total nutrients (N+P+K ≥ 5.5%) and heavy metals (Pb ≤ 0.40 mg/kg, Cr ≤ 1.50 mg/kg, Cd ≤ 0.40 mg/kg) in the residues of this study met the Chinese standard for organic fertilizer. Tilapia raised with the dried housefly larvae showed the best growth performance and nutrient concentrations in the experiment groups (p < 0.05). Moreover, the trace elements concentration in tilapia raised with the four kinds of feeds complied with the maximum levels of contaminants in foods in both China and WHO. These findings show that the housefly larvae products that converted food waste are suitable for use in the production of fish feed.

This study evaluated the effect of applying biofertilizer in the soil on the cultivation of corn. Different doses of biofertilizer associated with chemical fertilizer were applied in the soil to meet the plants’ nutritional demand. Four months after sowing, plant samples were collected and evaluated, by measuring the height and productivity of biomass, dry matter, neutral detergent fiber (NDF), acid detergent fiber (ADF), crude protein (CP), and nitrogen (N). Soil samples were also collected to measure the concentrations of macronutrients, base saturation, and exchangeable acidity. The biofertilizer application did not alter the levels of dry matter, NDF, ADF, CP, and N in the plants, or the concentrations of nitrogen, phosphorus, magnesium, and copper in the soil. Besides this, the largest average values of the plant heights and levels of potassium in the soil were found in the treatment with the highest biofertilizer dose. Notably, there was a significant increase in the quantity of fresh and dry matter in the treatments that received biofertilizer in comparison with the controls. The results obtained indicated the potential of substituting conventional fertilization with fertirrigation using biofertilizer, an alternative procedure that can help reduce the environmental impacts caused by dairy farming, regarding the release of wastewater into watercourses.

The dephenolization of palm oil mill effluent (POME) with oil palm fiber-immobilized Trametes hirsuta AK 04 was conducted in a temporary immersion bioreactor to reduce the inhibitory effects of phenolics in anaerobic digestion. Longer immersion times provided greater removal of phenolics due to a higher release of manganese peroxidase. The most effective dephenolization was observed at 6 h immersed and 2 h non-immersed time (immersion ratio 6/8) with maximum removal of 85% from 1277 mg L⁻¹ of phenolics in 4 days. The immobilized fungus maintained its high activity during multiple repeated batch treatments. The pretreated POME of 2 h showed higher methane yields compared with the untreated POME substrate. The methane yields increased with increasing pretreatment time and dephenolization levels. The results suggested that an increased abundance of methanogens was associated with the detoxification of phenolics. The fungal biomass contained crude protein, amino acids, and essential phenolics, which can be used as animal feed supplements.

The effects of a composite polyphenolic-rich extract (CPRE) on ruminal fermentation, nutrient utilisation, growth performance, excretion of nitrogen and phosphorus and methane emission were studied in growing buffaloes. Four herbal dry extracts prepared from Acacia arabica (babul; bark), Acacia catechu (cutch; bark), Punica granatum (pomegranate; peel) and Eugenia jambolana (Indian blackberry; seeds) were mixed in an equal proportion (1:1:1:1) to prepare the CPRE that contained mainly phenolic compounds (146 g/kg), flavonoids (41.7 g/kg) and saponins (40.5 g/kg). First, in vitro tests were performed for ruminal fermentation and feed degradability using ruminal fluid as inocula and CPRE at 0 to 40 g/kg substrate to decide an optimal dose of CPRE for an in vivo study on buffaloes. In the animal study, 20 buffaloes were randomly assigned to two groups (n = 10)—a control diet and a CPRE diet (control diet added with extra 20 g/kg of CPRE). The in vitro tests suggested that addition of CPRE at 20 g/kg substrate increased degradability of substrate, short-chain fatty acid concentration and propionate proportion, and reduced methane production, acetate proportion, acetate:propionate ratio and ammonia concentration in fermentation media, which were also noted in the rumen of buffaloes. Feeding CRPE to buffaloes did not affect feed intake, but increased daily body weight gain, dry matter and crude protein digestibility and nitrogen and phosphorus retention in the body. Total bacteria, methanogens and protozoal numbers were similar between two groups, but Fibrobacter succinogenes increased in the rumen of buffaloes fed CPRE. Concentrations of total, essential, non-essential and glucogenic amino acids were greater in the plasma of CPRE-fed buffaloes. Cell-mediated immune response improved in the CPRE-fed buffaloes compared with the control group. Estimated methane production and excretion of nitrogen and phosphorus per unit of body weight gain decreased in the CPRE group. The comprehensive results of this study clearly suggested that the composite polyphenol-rich feed additive at 20 g/kg diet improved growth performance, ruminal fermentation, immunity and plasma amino acids profile, whereas it reduced indicators of environmental impacts of buffalo production.