Digestibility and nutrient utilization of soybean milk concentrate based diets in Oreochromis niloticus

The digestibility and utilisation of two fresh soybean milk concentrate based diets, two stale soybean milk concentrate based diets and two Fishman based diets serving as control, at optimal (30%) and suboptimal (20%) protein levels were evaluated in Oreochromis niloticus. The diets were as follows: Diet I (control) - fishmeal based diet at 30% crude protein, Diet II (control) Fishman based diet at 20% crude protein, Diet III - fresh soybean milk concentrate based diet at 30% crude protein, Diet IV - fresh soybean milk concentrate based diet at 20%, Diet V - stale soybean milk concentrate based diet at 30% crude protein, Diet VI-stale soybean milk concentrate based diet at 20%. Dry matter digestibility differed not significantly with variation in diets (P:0.05). A significant variation was recorded in the protein, lipid and ash digestibility. Proteins were more digestible at optimum than suboptimum level. Ash digestibility was lowest of all the nutrients. Variations in the utilisation of the diets in terms of weight gain, specific growth rate, food conversion ration, protein efficiency ration and apparent net protein utilization were insignificant (P: 0.05). All diets compared favourably with the standard control diet Diet I. This findings suggest the suitability of stale soybean milk concentrate utilisation as protein supplements in the diets of late fry Oreochromis niloticu

Is there an optimal diet for weight management and metabolic health?

Individuals can lose body weight and improve health status on a wide range of energy (calorie) restricted dietary interventions. In this paper, we have reviewed the effectiveness of the most commonly utilized diets, including low-fat, low-carbohydrate and Mediterranean approaches in addition to commercial slimming programmes, meal replacements and newly-popularized intermittent fasting diets. We also consider the role of artificial sweeteners in weight management. Low-fat diets tend to improve LDL-cholesterol most, whilst lower-carbohydrate diets may preferentially improve triglycerides and HDL-cholesterol, however differences between diets are marginal. Weight loss improves almost all obesity related co-morbidities and metabolic markers, regardless of the macronutrient composition of the diet, but individuals do vary in preferences and ability to adhere to different diets. Optimizing adherence is the most important factor for weight loss success, and this is enhanced by regular professional contact and supportive behavioral change programs. Maintaining weight losses in the long-term remains the biggest challenge, and is undermined by an ‘obesogenic’ environment and biological adaptations that accompany weight loss

Nitrogen and energy partitioning in two genetic groups of pigs fed low-protein diets at 130 kg body weight

The aim was to evaluate the effect of low-protein (LP) or low-amino acid diets on digestibility, energy and nitrogen (N) utilisation in 2 genetic groups (GG) of pigs (129±11 kg BW). Duroc×Large White (A) pigs were chosen to represent a traditional GG for ham production, and Danbred Duroc (D) pigs to represent a GG with fast growing rate and high carcass lean yield. Dietary treatments: a conventional diet (CONV) containing 13.2% CP, and two LP diets, one with LP (10.4%) and low essential AA (LP1), the second with LP (9.7%) and high essential AA (LP2). Compared to CONV, LP2 had the same essential AA content per unit feed, while LP1 the same essential AA content per unit CP. Feed was restricted (DMI=6.8% BW0.75). Four consecutive digestibility/balances periods were conducted with 24 barrows, 12 A and 12 D. Metabolic cages and respiration chambers were used. No significant difference between diets was registered for digestibility. Nitrogen excreted: 41.3, 33.4 and 29.0 g/d (P=0.009), for CONV, LP1 and LP2 diets, respectively. Nitrogen retention was similar between the diets. Heat production (HP) was the lowest for LP diets. There was a tendency (P=0.079) for a lower energy digestibility in D group. The D pigs also had a higher HP and hence a lower retained energy in comparison with the A pigs. In conclusion: it is possible to reduce N excretion using very LP diets and LP-low AA diets; Danbred GG have a higher heat production and a lower energy retention than A pigs

Female and male Wistar rats (Rattus norvegicus) discriminate diets according to energetic quantity

The food choice of animals is influenced by several factors including the quantity and nutrients available. It is not known, however, whether faced with alternatives that present the same amount of food, with similar flavor and obtained with the same response cost, rats would discriminate between diets with different energetic quantities. The aim was to verify whether female and male Wistar rats (Rattus norvegicus) discriminate between three types of food that differ in their energetic content (whether or not they prefer one) and whether the flavor could affect the choice between two diets with equal energetic quantities. Twelve Wistar rats (six of each sex) underwent tests of choice between pairs of diets of different energetic values. After the tests, the animals had at their disposal, in the home cage, two diets with the same energetic content, which differed in flavor (one contained sucrose) - Flavor test. The consumption of each diet was measured for five consecutive days. All the subjects demonstrated a preference for the more energetic alternative, regardless of the combination of diets presented. In the Flavor test the animals did not show significant preference for any diet, i.e., the consumption of both the S and N diets were statistically equal for all subjects. It was concluded that the animals, regardless of sex, discriminated between the diets with different energetic values and that the flavor did not seem to be a determinant variable in the food choice.

Calcium and magnesium absorption and retention by growing goats offered diets with different calcium sources

Calcium addition is necessary in order to balance the high phosphorus concentrations that are characteristic of high-concentrate ruminant diets. However, calcium sources differ in their bioavailability. Our objective was to determine apparent calcium and magnesium absorption and retention in goats offered diets containing different sources of calcium. Spanish-Boer goats (n = 18; 19.6 ± 1.88 kg) were stratified by body weight (BW) and sex and randomized to dietary treatments consisting of Purina Antlermax 16 containing either calcium carbonate (CC), Calmin (CM) or Milk Cal (MC). Goats were adapted to a control, corn-based high-concentrate diet on pasture and then moved to individual 1.0 × 1.5-m pens with plastic coated expanded metal floors, and adjusted to their respective diets along with removal of hay from the diet over a 7-d period. Goats were then offered their respective diets at a total of 2% of BW in equal feedings at 8:30 AM and 5:00 PM for an additional 14-d adaption period to diet and facilities followed by a 7-d collection of total urine and feces. Data were analyzed using PROC MIXED of SAS. Calcium and magnesium intake were not different (P ≥ 0.12) among diets. Calcium and magnesium apparent absorption and retention (g/d and % of intake) were greatest (P \u3c 0.05) in goats offered CC and did not differ (P ≥ 0.20) between goats offered the CM and MC diets. Therefore, calcium and magnesium were more available for goats from the diet containing calcium carbonate compared with diets containing Calmin and Milk Cal

Lupin ingredients in shrimp (Penaeus monodon) diets: influence of lupin species and types of meals

The nutritive value of five isonitrogenous practical diets containing different legume meals, whole or dehulled lupin (Lupinus albus) seed meal (WAD and DAD, respectively), dehulled lupin (L. angustifolius) seed meal (DND), lupin (L. angustifolius) protein concentrate (LPCD), and defatted soybean meal (SBD), was evaluated in two laboratory experiments (growout and digestibility studies) using juvenile (4.07±0.05 g, mean±SD) shrimp, Penaeus monodon. In the 42-day growout study, shrimp fed SBD or DND had significantly higher (P<0.05) growth rates than those fed LPCD, DAD or WAD. Protein conversion efficiency (PCE) and apparent protein utilization (APU) values of DND were significantly higher than those of LPCD, DAD or WAD. SBD and DND had significantly higher feed intake values and better feed conversion ratios (FCRs) than WAD and DAD. LPCD had a similar FCR to other diets but lower feed intake than SBD. Shrimp fed WAD had significantly poorer performance in all the above parameters than shrimp fed other diets except for DAD and LPCD. The diets SBD, DND, LPCD, and DAD had significantly higher (P<0.05) apparent dry matter digestibilities (ADMD) (68.3–71.4%) than WAD (64.4%). All diets had a similar apparent protein digestibility (APD) (87.1–89.1%) with a small, but significant difference being observed for the diets with the highest (DND) and the lowest (WAD) protein digestibility. Pellet water stability was significantly different (P<0.05) among the diets. The most stable pellet was displayed by LPCD, while WAD had the poorest water stability. Dehulling or concentrating lupin seed protein did not improve the nutritive value of lupin diets for juvenile P. monodon. The lupin seed meal of L. angustifolius was better utilized by P. monodon than that of L. albus and the nutritive value of L. angustifolius diet was equal to that of soybean (control) diet. Results of a feeding preference test also indicated that L. angustifolius diet was more attractive for juvenile P. monodon than L. albus diet

Rats show individual preference for short-term choice of three human diets

A preference test was conducted to investigate whether rats could distinguish among three iso-energetic and iso-nitrogeneous human diets prepared with ingredients cultivated by each of three different farming strategies: LIminusP: low input of feritlizer without pesticides, LIplusP: lowinput of fertilicer and high input of pesticides and LHplusP: high input of fertilizer and high input of pesticides. The experimental diets were formulated to meet the NRC requirements for growing rats by mixing potatoes, carrots, peas, green kales, apples, and rapeseed oil. For five days, rats (N=27) had free access to each of the three diets, and consumption of each of the diets was recorded daily. Thereafter, rats were offered a standard laboratory chow until the test was repeated. The results indicated that the majority of the rats showed individual preference for the diets and behaved similarly on different experimental days (ρ = 0.63 in repetition 1 and ρ = 0.73 in repetition 2) and in the two repetitions (τ = 0.79). However, no clear difference among the dietary treatments could be obtained

Feeding weaned piglets and growing-finishing pigs with diets based on mainly home-grown organic feedstuffs

In 2000, EU regulations for organic animal production set new guidelines for organic pig feeding requiring that this be based on mainly home-grown organic feedstuffs. Doubts were however raised whether these feeding regimes can maintain good growth performance and carcass quality of pigs. Three experiments were carried out to study different organic feeding regimes in weaned piglets and fattening pigs. In Experiment 1, we evaluated the use of peas and faba beans (0, 120, or 240 g kg-1) in diets for weaned piglets. Piglets fed pea diets performed as well as those fed the control diet, whereas the highest faba bean level resulted in reduced feed intake and growth performance. In Experiment 2, we studied the replacement (0, 33, or 67%) of rapeseed cake with blue lupins in fattening pig diets. The dietary lupin level had a quadratic effect on the weight gain of growing pigs, the best performance being observed at the 33% replacement level. However, dietary lupin level did not influence weight gain during the finishing period and total fattening. Back fat became softer with increasing dietary lupin levels. In Experiment 3, different protein supplements were compared in organic diets from weaning to slaughter. In two-phase feeding, the best performance was observed when whey protein was used as the protein supplement, followed by soya bean cake + whey protein and rapeseed cake + fish meal. The effects of a one-phase organic feeding regime with cold-pressed rapeseed cake + whey protein did not differ from those of the two-phase organic feeding regimes. Fattening pigs fed organic diets required from two to seven days longer to reach slaughter weight than those fed conventional diets. Pigs fed organic diets had fatter carcasses, but the eating quality of organic pork did not differ from that of pork from pigs fed conventional diets. Feed costs and the circulation rate of pigs, weaners in particular, were greater and carcass prices lower in the organic feeding regimes than in the conventional ones

Performance and intestinal responses to dehulling and inclusion level of Australian sweet lupins (Lupinus angustifolius L.) in diets for weaner pigs

A total of 180 entire male weaner pigs weighing 6.4 ± 0.1. kg (mean ± SEM) and housed in pairs was used in a completely randomised block design with 9 dietary treatments (n= 10 pens). Pigs were blocked based on weaning weight. The diets were (i) a wheat-based control diet containing 240. g/kg of milk products (whey and skim milk powder), and (ii) 8 diets containing whole or dehulled lupins (cv. Coromup) that substituted the milk products at 60, 120, 180 and 240. g/kg of diet (replace 25%, 50%, 75%, or 100% of the milk products in the control diets). The diets were isoenergetic [15. MJ digestible energy (DE)/kg], and were formulated to contain the same ileal standardised digestible lysine content (0.85. g/MJ DE) and ideal patterns of other essential amino acids. Pigs receiving 240. g/kg of dehulled lupins grew slower (P<0.05) than pigs fed the other diets mainly due to decreased feed intake. Pigs fed diets containing more than 180. g/kg of dehulled lupins had a higher faecal β-haemolytic Escherichia coli score on day 3 after weaning (P<0.05). Moreover, inclusion of 240. g/kg of whole lupin or more than 180. g/kg of dehulled lupins increased (P<0.001) plasma urea nitrogen (PUN) levels. Total tract apparent digestibility (TTAD) of dry matter decreased (P<0.001) in all lupin diets compared with the control diet. These data indicate that inclusion of dehulled lupin immediately after weaning should be limited to less than 180. g/kg whilst whole lupins can be included up to 240. g/kg without deleterious effects on production and intestinal health