Archives of Animal Nutrition最新文献

Preserved feed from meadows contaminated with ragwort (Jacobaea vulgaris, Gaertn.) may expose livestock to pyrrolizidine alkaloids (PA). Dairy cows are considered to be very susceptible animals and a PA ingestion can lead to liver and further organ damages and even death. Due to the lack of data, the present study aimed to evaluate critical PA doses based on organ effects, with a special focus on liver lesions and on indicators of energy metabolism. Therefore, 16 dairy cows (n = 4 per group) were exposed to increasing PA doses (group: CON_Molasses: <0.001 mg PA/kg body weight (BW)/day (d); PA1: 0.47 mg PA/kg BW/d; PA2: 0.95 mg PA/kg BW/d; PA3: 1.91 mg PA/kg BW/d) for 28 days. Constant dosing was ensured by a defined PA extract administered orally once daily. Histological examinations of the livers showed infiltration by immune cells, higher proportions of apoptotic cells and enlargement of hepatocyte nuclei in the highest exposed group. In addition, bile volume increased with PA dose, which may indicate a cholestasis. Despite the signs of incipient liver damage, liver lipid content and clinical chemical parameters related to energy metabolism, such as glucose, non-esterified fatty acids and βhydroxybutyrate, remained unaffected. Fat depot masses were also not significantly altered over time, suggesting that PA exposure did not induce a wasting syndrome. The liver showed slight microscopic changes already at a dosage of 0.95 mg PA/kg BW/d. However, the short-term metabolic indicators of energy status, lipolysis and ketogenesis, glucose, NEFA and BHB, as well as changes in fat depot, which serves as a longer-term indicator of lipolysis, remained unaffected in all treatment groups in the chosen scenario. These findings suggest that despite histopathological and clinical-chemical evidence of PA-associated hepatocellular lesions, liver function was not compromised.

Supply problems and rising soybean meal prices have an impact on increasing feed costs. Hemp seed meal (HSM) with high protein content has the potential to be used as an alternative to soybean meal. This study evaluated the impact of dietary HSM of Narlı Sarayı variety as a substitute for soybean meal on productive performances, egg quality and yolk fatty acid composition. A total of 120 Lohmann Brown laying hens aged 50 weeks were allocated into 4 groups and 10 repetitions. Birds received treatment without HSM (control group), or soybean meal substituted with 4%, 8% and 12% HSM. Dietary 4% significantly increased (p < 0.05) egg production and decreased FCR compared with 8% and 12% HSM group but did not differ from the control group in an overall period of 6 weeks. The inclusion of the 12% HSM group significantly decreased (p < 0.05) egg production. Meanwhile, there was no influence of hemp seed meal (p > 0.05) on feed intake, egg weight, body weight change, egg shape index, albumen index, albumen weight, Haugh unit, yolk weight, yolk index and eggshell thickness. Dietary 8% and 12% HSM significantly increased (p < 0.05) eggshell weight and yolk colour compared with control and 4% HSM groups. There was a significant increase (p < 0.05) in omega-3 fatty acid concentration and a decrease in yolk omega-6 to omega-3 fatty acids ratio with an increase in dietary HSM. It was concluded that dietary up to 12% HSM of the Narlı Sarayı variety decreased egg production and increased FCR. Increasing dietary levels of HSM increased eggshell weight, yolk colour and omega-3 fatty acids content and decreased the omega-6 to omega-3 fatty acids ratio.

Cassava protein (CP), barley protein (BP) and yellow pea protein (YPP) are important nutrient and integral constituent of staple in pet foods. It is known that the digestion of proteins directly influences their absorption and utilisation. In the present work, we performed in vitro simulated gastrointestinal digestion of three plant proteins as a staple for dog and cat food. The digestion rate of CP, BP and YPP in dog food was 56.33 ± 0.90%, 48.53 ± 0.91%, and 66.96 ± 0.37%, respectively, whereas the digestion rate of CP, BP, and YPP in cat food was 66.25 ± 0.72%, 43.42 ± 0.83%, and 58.05 ± 0.85%, respectively. Using SDS-polyacrylamide gel electrophoresis to determine the molecular weight (MW) of each protein and the products of their digestion, it was revealed that MW of digestion samples decreased, and MW during the small intestine phase was lower than that during the gastric phase. Peptide sequences of digested products were identified by liquid chromatography-tandem mass spectrometry (LC-MS/MS), and it was found that the total number of peptides in the small intestine digestion samples was higher than that in the gastric phase samples. The MW of peptides obtained from CP was within the range of 1000-1500 Da, while MW of peptides derived from BP and YPP was within the range of 400-2000 Da. In addition, free amino acids were mainly produced in the small intestine phase. Furthermore, the percentage of essential amino acids in the small intestine phase (63 ~ 82%) was higher than that in the gastric phase (37 ~ 63%). Taken together, these findings contribute to the current understanding of the utilisation of plant proteins in dog and cat foods and provide important insights into the selection and application of plant proteins as a staple in dog and cat foods.

Farmgate balances are used as a tool for monitoring nutrient surpluses at farm level. In Germany, preparation of farmgate balances is legally mandatory and also requires data on chemical body composition, especially concentration of nitrogen (N) and phosphorus (P), of farm animals. It is well known that increased N and P efficiency results in lowered N and P excretions with the manure and therefore mitigates negative consequences of high N and P release into the environment (e.g. eutrophication of surface waters), especially in areas with high livestock density. In this context, feeding N- and P-reduced diets can be a strategy for increasing N and P efficiency in fattening pigs. To investigate the influence of N- and P-reduced diets on chemical body composition of barrows and to update current used data basis, 8 barrows were slaughtered after a balance trial and their bodies were subjected to full body analysis. During the balance trial, pigs received the control diet (CON) meeting common nutrient requirements or the N- and P-reduced diet (NPred) in a three-phased feeding regimen (n = 4/diet, 3 weeks/phase). Pigs were slaughtered with an average live weight (LW) of 123.3 ± 7.5 kg and carcasses were manually dissected in four fractions. Fractions were analysed for nutrient concentration. Furthermore, organs were weighed individually and blood serum was sampled during exsanguination. Serum samples were analysed for clinical-chemical traits. Chemical body composition did not significantly differ between NPred- and CON-fed pigs. N concentration was 23.3 ± 0.3 and 24.5 ± 1.0 g/kg, P concentration was 5.2 ± 0.1 and 5.5 ± 0.4 g/kg in the empty body of NPred- and CON-fed pigs (p = 0.073, 0.164). N and P retention between the experiment's start and slaughter did not differ between the feeding groups (p = 0.641, 0.240). Variables related to liver integrity, energy metabolism and electrolytes were similar between CON- and NPred-fed pigs. Traits related to protein metabolism showed significantly reduced concentrations of urea and albumin in NPred-fed pigs (p = 0.013, 0.025), but no hypoalbuminaemia. Results suggest that N- and P-reduced feeding does not significantly affect chemical body composition of contemporary barrows.

This study aimed to evaluate intake, energy and nitrogen balance as well as methane emission in Holstein and ½ Holstein ½ Gyr (Girolando-F1) cows during the transition period. Twenty-four cows (12 Holstein and 12 Girolando-F1) were used to evaluate feed intake, apparent digestibility, heat production and methane emission, carried out in two periods: from 28 to 19 days pre-calving and from 15 to 23 days post-calving. A completely randomised design was used and data were analysed by ANOVA within periods (pre- and post-calving) considering the main effect of genetic groups. Girolando-F1cows presented greater body condition score (BCS) compared with Holstein. During pre-calving, there were no differences between genetic groups, except for highest heat production per kilogram of metabolic body weight for Holstein cows. After calving, Holstein cows had greater intake of DM, nitrogen, NDF per kg of BW and produced more heat per kg of metabolic body weight. Holstein cows yielded more milk and fat-corrected milk (FCM_4%) compared with Girolando-F1 cows. Holstein cows presented higher methane emission per unit of BW and of metabolic weight. Emissions of enteric methane per kilogram of milk and per kilogram of FCM_4% tended to be lower for Holstein compared with Girolando-F1 cows. Nitrogen and energy retention were similar for both Holstein and Girolando-F1 at pre- and post-calving. Despite differences in BCS, DMI, and milk yield, Girolando-F1 and Holstein cows present overall similar energy efficiency, albeit Holstein cows tended to present less methane emission per kg of eligible product (milk).

Hydrolysed proteins have been shown to be potential ingredients in cat diets due to their high digestibility, presence of bioactive peptides, and relatively low antigenicity. The effects of the substitution of conventional low ash poultry byproduct meal (PBM) with hydrolysed poultry byproduct meal (HPM) as a protein source were evaluated in extruded cat diets. Five diets with similar nutrient contents were formulated: a control (CO) diet based on PBM and 4 diets with different inclusions of HPM (5%, 10%, 20%, and 30%, on an as-fed basis) replacing PBM as the protein source. The total tract apparent digestibility (CTTAD) of nutrients, faecal characteristics and microbial fermentation products, urine production and pH, nitrogen balance and urea renal excretion were evaluated using 30 healthy cats (15 males and 15 females; 4.18 ± 0.86 kg; 4.17 ± 1.38 years old), with 6 cats per diet in a complete randomised block design. When significant differences were found with the F test, the effects were evaluated by polynomial contrasts according to HPM inclusion (p < 0.05). The CTTADs of DM (89 ± 0.41%), CP (90 ± 0.36%), fat (93 ± 0.41%) and gross energy (90 ± 0.33%) were similar among treatments (p > 0.05). The faecal production, score, short-chain fatty acids and ammonia concentration were similar among treatments (p > 0.05). Isobutyric, isovaleric, valeric, and total branched-chain fatty acid contents increased quadratically (p < 0.05), with the highest level in the faeces of cats fed the diet with 20% HPM. Lactate concentration in faeces increased linearly with the inclusion of HPM (p < 0.05). Urine characteristics and urea renal excretion did not differ among treatments (p > 0.05). At 10% inclusion, HPM tended to increase the nitrogen retention of cats (p = 0.083), which may reflect the higher tryptophan, methionine, lysine, and available lysine contents of HPM in comparison to PBM. The inclusion of up to 30% HPM can be considered in cat formulations without affecting nutrient digestibility or faecal and urine characteristics. HPM tended to increase nitrogen retention and increased branched-chain fatty acids in faeces, aspects which deserves further studies.

This study was performed to investigate the nitrogen (N) and carbohydrate digestive traits of grazing heifers. The experiment was carried out at the Federal University of Lavras. The treatments were a Marandu palisadegrass (Urochloa brizantha [Syn, Brachiaria brizantha] Stapf. A. Rich. cv. Marandu) monoculture fertilised with 150 kg N/[ha ∙ year] (FP) or Marandu palisadegrass mixed pasture with forage peanut (MP). The pastures were grazed by six rumen-cannulated zebu heifers. A double cross-over design was used in four periods. Nutritive value, intake and apparent digestibility of forage, ruminal traits and kinetics and N balance were evaluated. Apparent total-tract digestibility of dry matter (DM) and neutral detergent fibre (NDF) were greater for FP than for MP. There was no effect in apparent total-tract digestibility of N. The estimated intestinal digestibility of nutrients was greater on MP than FP. Even though N intake and faecal N output were greater on MP than FP, there was no effect in urine N output. The N balance tended to be greater on MP than FP. The forage peanut, which contains condensed tannins, decreased ruminal fibre degradation, apparent digestibility and ruminal protein degradation, increased N flow from the rumen. Inclusion of forage peanut in the mixed pasture decreased the ruminal fibre degradability but increased N retention by the animals.