Journal of Animal Physiology and Animal Nutrition最新文献

Raw meat-based diets (RMBDs) for pets, which contain raw meat from livestock, aquatic species, or wild-captive animals, are known to harbour feed-borne pathogens and antimicrobial-resistant (AMR) bacteria. This study investigated the contamination of extended-spectrum β-lactamase (ESBL)-producing Escherichia coli, Salmonella, Enterococcus faecalis, and E. faecium in Thai RMBD products, focusing on their AMR phenotypic and genotypic properties. A total of 50 RMBD samples and five fresh-cooked diets (FCDs) were analysed for total aerobic colony counts (ACC) and the presence of third-generation cephalosporins (3GC)-resistant E. coli, Salmonella, E. faecalis, and E. faecium. The AMR phenotypes of isolated bacteria were determined using antimicrobial susceptibility testing and ESBL production, while bla_CTX-M and mcr genes were detected by PCR assays. ACCs in RMBD samples were higher than those in FCD samples. The RMBD products tested positive for 3GC-resistant E. coli (n = 40, 80.0%), Salmonella spp. (n = 35, 70.0%), E. faecalis (n = 50, 100%), and E. faecium (n = 42, 84.0%). All 3GC-resistant E. coli isolates were ESBL producers carrying bla_CTX-M group 1 and group 9. Among the Salmonella isolates, five ESBL-producing S. Infantis isolates carried bla_CTX-M group 9. Two ESBL-producing E. coli and seven Salmonella isolates exhibited colistin resistance. No vancomycin resistance was observed in the enterococcal isolates. These findings underscore the high prevalence of Salmonella and ESBL-producing E. coli in RMBD products, emphasising the potential health risks associated with RMBD consumption for pets. This study highlights the need for awareness and preventive measures to mitigate AMR spread through pet foods.

In our trial, we investigated the effects of including dietary fats, specifically tallow and palm oil (PO), on growth performance and nutrient digestibility in finishing pigs. Additionally, we assessed their impact on backfat thickness, carcass grade, meat quality, and the fatty acid (FA) profile of the meat. In total, 160 finishing pigs ([Landrace × Yorkshire] × Duroc) with an average body weight (BW) of 50.36 ± 1.59 kg ([16 replications/treatment, five pigs] [two gilts and three barrows]/treatment, 12-week trial) were arbitrarily distributed to 1 of 2 dietary treatments: TRT1, basal diet + tallow (2.8%); TRT2, basal diet + PO (2.8%). At Week 8, there was an increased average daily feed intake and decreased feed conversion ratio in the PO diet compared to the tallow diet (p < 0.05). The digestibility of nutrients, backfat thickness, and carcass grade did not change substantially (p > 0.05). The PO-included diet increased sensory evaluation and water holding capacity of meat compared to the tallow diet (p < 0.05). PO-supplemented pigs showed higher (p < 0.05) FA percentages of palmitoleic acid (C16:1), margaric acid (C17:0), arachidic acid (C20:3n3), ω-3 FA, ω-6: ω-3, ΣPUFA (polyunsaturated FA), and MUFA (monounsaturated FA) than the tallow diet. Moreover, the percentage of linoelaidic acid (C18:2n6t), ΣUSFA (unsaturated FA), and PUFA also tended to increase (p < 0.10) in the PO-included diet. In summary, the inclusion of PO in the diet positively influenced growth performance, meat quality, and the FA profile, indicating its potential as a beneficial fat supplement for finishing pigs. These results, obtained from a 12-week trial under controlled conditions, support the use of dietary PO to improve production performance in finishing pigs. However, further studies are necessary to investigate the long-term effects, dose-response relationships, and potential interactions with environmental and genetic factors under varied commercial conditions.

This study examined the impact of drying methods and various chemical treatments on the ruminal protein degradability and the intestinal digestibility of mealworm larvae (Tenebrio molitor, TML). The TML was drying using oven-drying and freeze-drying (lyophilization) methods. Tannic acid and formaldehyde were applied to the TML. Tannic acid was applied at three doses (30, 60, and 90 g/kg of the dry matter content), or formaldehyde was used at a concentration of 0.8% of the crude protein content in the dry matter to treat TML. The in-situ nylon bag technique was employed to ascertain the degradability of protein in the rumen, while the in vitro method was used to determine the intestinal digestibility. Consequently, the freeze-drying technique significantly improved the protein content and the presence of essential amino acids in TML. The ruminal degradability of TML protein decreased in oven drying and chemical treatments, that mostly in formaldehyde treatment. The intestinal protein digestibility was improved in the oven-dried samples by chemical treatments. While freeze-drying is suggested to improve protein quality, it has been found that oven drying, formaldehyde treatment, or treatment with 90 g/kg tannic acid effectively increases the ratio of bypass protein and intestinal digestibility.

Analysing the development of a digestive system and enzyme activity is crucial for understanding the digestive physiology of larval fish and determining optimal feeding practices. The white-barred goby (Amblygobius phalaena), a popular marine ornamental fish, has established breeding and larval rearing techniques, but research on its digestive physiology remains limited, which is essential for enhancing commercial production efficiency. This study aimed to elucidate the histological structure of the digestive tract and changes in enzyme activity in white-barred goby larvae to understand the progression of their digestive functions, providing a foundation for future weaning studies. Histological observations revealed that 6–8 h before hatching, the digestive tract appeared as a simple straight tube, with the liver, pancreas and gallbladder already formed. Gastric glands developed by 35 days post-hatch (dph), at which point the larvae reached a total length of 15.70–18.50 mm. The stomach reached full development at 40 dph (20.11–25.12 mm). Analysis of digestive enzyme activity showed that the total activities of trypsin, amylase, lipase and pepsin in white-barred goby larvae gradually increased with growth. Lipase and pepsin specific activities peaked at 40 dph (19.58–25.13 mm). Based on these results, we recommend to introduce artificial feed starting from 35 dph (15.70–18.50 mm). The findings of this study are significant for improving larviculture and establishing the weaning time of white-barred goby larvae.

The present work aimed to evaluate the influence of a training programme on energy expenditure (EE), cost of transport (COT, cardiac beats to move the body mass during exercise) and metabolic power (Pmet) in young Purebred Lusitano horses used in dressage. With this purpose, nine male horses, ~4 years old, were evaluated before (M1) and after 6 weeks (M2) of a training programme that included 40−80 min of preparatory dressage exercises, 6×/week, individually adjusted. In M1 and M2, the animals were examined in a dressage field test (DFT), when heart rate (HR) and respiratory rate (RR), body temperature (BT) and blood lactate were recorded. In DFT, the horses used a cardiac monitor (Polar H10) for calculation using the formulas: EE (J/kg/min) = 0.0566 × HR^1.9955, COT = (HR_effort−HR_basal)/kg/m × 10³ and Pmet (beats/min/kg) = (HR − 35)/min/kg. The training led to a significant reduction in EE (799.9 vs. 682.8 J/min; p = 0.037) and COT (0.73 vs. 0.59 bpm/kg/m × 10³; p = 0.042), without change in Pmet. Furthermore, a significant increase in peak of speed was observed (5.81 vs. 7.36 m/s; p = 0.0161). It was possible to conclude that the proposed training protocol led to greater efficiency in locomotion costs, with lower EE and COT values.

The search for safe and effective alternatives to antibiotics in poultry production has intensified due to growing concerns over antimicrobial resistance and food safety. Postbiotics, derived from beneficial microorganisms, have emerged as promising candidates to enhance broiler health and performance. We evaluated the effects of Zophobas morio-based postbiotics on broiler chickens' growth performance, nutrient digestibility, immunity, intestinal health, and economic viability. Z. morio larvae were cultured with Lactobacillus acidophilus (3 × 10⁹ CFU/mL) in wheat bran to produce postbiotics. We used a total of 350 Ross 308 broiler chicks were allocated into five groups, with one control group and four treatment groups supplemented with 0.2%, 0.4%, 0.6% or 0.8% Z. morio-based postbiotics. Treated groups exhibited significantly improved weight gain, nutrient digestibility, and apparent metabolisable energy compared to the control group. The microbial count of L. acidophilus increased significantly (p < 0.05), while pathogenic bacteria such as Salmonella and E. coli decreased, particularly in the 0.8% postbiotic group. Intestinal morphology, including villus length and width and crypt depth, improved in postbiotic-supplemented groups. Additionally, carcass yield and economic returns were higher in the 0.8% treatment group. Immune responses were enhanced, with higher antibody titers against Newcastle disease (ND) at 0.6% and 0.8% inclusion levels. The study concluded that Z. morio-based postbiotics at the level of 0.8% positively influenced broiler growth performance by enhancing nutrient absorption, boosting immunity, and reducing pathogenic bacteria.