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The influence of grain type and fat source on the performance, coefficient of apparent ileal digestibility (CAID), and intestinal characteristics in broiler starters fed pelleted diets were studied. The experiment included 8 treatments arranged as a 2 × 4 factorial with 2 grains (wheat and corn) and 4 fat sources (soybean oil, fish oil, tallow, and palm oil). In all fat sources, corn-fed birds had a higher weight gain than those fed wheat-based diets. However, improvement in the weight gain of birds fed wheat-based diets supplemented with tallow resulted in a significant (P < 0.001) interaction between grain type and fat source. Inclusion of wheat and tallow increased feed intake compared to corn and other fat sources, respectively. Pellets made from wheat were harder (P < 0.01) than those based on corn. Broilers fed corn-based diets, had higher CAID of fat, Ca, and phosphorus (P < 0.01) than those fed wheat-based diets. Soybean oil inclusion, also increased (P < 0.01) fat digestibility compared to other fat sources. An interaction occurred between grain type and fat source where pellets made from corn and soybean oil had higher protein digestibility compared to the other treatments (P < 0.01). Feeding wheat-based diets increased pH of gizzard and proventriculus compared to corn-based diets (P < 0.01). Highest viscosity value was observed in wheat-diets supplemented with fish oil, and palm oil (P < 0.01). The pancrease, gizzard and cecum were heavier in corn-based fed birds compared to those fed wheat-based diets (P < 0.01). A significant interaction between grain type and fat source was noted for Lactobacillus spp. and the total anaerobic bacteria population in the cecum. Overall, the effect of grain type on weight gain, CIAD of protein and cecal microbiota differed depending on the fat sources. Feeding corn and soybean oil resulted in better gut development and growth performance in broilers fed pelleted diets.

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1. An experiment was conducted to determine the effect of the source of fat (soybean oil or tallow) on the ileal endogenous amino acid (EAA) losses in broilers.2. Three nitrogen (N)-free diets; a control diet with no added fat and test diets with 60 g/kg of either soybean oil or tallow were formulated. Titanium dioxide (5 g/kg) was added to all diets as an indigestible marker. Each diet was assigned to six replicate cages (eight birds per cage) from d 18 to 21 post-hatch. On d 21, the digesta were collected from the lower half of the ileum.3. The endogenous losses of nitrogen and amino acids (AA) were lower (p = 0.08; p = 0.001) in broilers fed diets with soybean oil or tallow, respectively, compared to those fed the diet with no fat. Source of fat had no influence (p > 0.05) on EAA losses.4. The most abundant AA in the ileal endogenous protein was glutamic acid, followed by aspartic acid, threonine, leucine, serine, valine and proline. In general, the concentrations of AA in the endogenous protein were lower (p < 0.05) with added fat. The exceptions were methionine, cysteine, proline and serine, which were unaffected. The effect of fat source on the AA contents of endogenous protein were inconsistent and differed depending on the AA.5. The inclusion of fats decreased EAA losses which implied they have beneficial effects beyond direct energy contribution. It can be proposed that the reduction of EAA flow may be an additional mechanism contributing to the extra-caloric effect of dietary fats.

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BACKGROUND: Nutritional manipulation with functional nutrients like polyunsaturated fatty acids can boost milk production efficiency in dairy farming. It is important to consider the animal's physiological periods, especially the second half of the first pregnancy for mammary gland development. OBJECTIVES: By considering multiple factors and comparing them, multi-attribute decision-making (MADM) can be utilized to conduct further assessments and select the best diet for the animals. METHODS: Forty primiparous Saanen does, from the last 2 months of pregnancy up to 4 months of lactation, have been assigned to four iso-energetic and iso-nitrogenous diets. Four dietary groups included: no external sources of fat (negative control, CT), saturated palm oil (positive control), roasted soybeans (omega-6, SB) and extruded flaxseed (omega-3, FS). Twenty-two performance criteria such as feed intake, milk yield and composition, body weight, blood metabolites and hormones, the milk fatty acid profile, as well as morphological and histological measurements of the mammary gland, in the form of least-square means, were considered. RESULTS: A decision-making tool was used to select the best form of fat supplements in late pregnancy and early lactation diets, to improve lactation performance in Saanen goats. For this purpose, a MADM method was applied to determine the order of preference similarity to the ideal solution. According to the score of this method, the FS group had the highest coefficients (0.689), and the CT group had the lowest coefficients (0.281). CONCLUSIONS: Incorporating flaxseed into the diets of Saanen goats during late pregnancy and early lactation is a valuable strategy for enhancing milk performance. This supplement is recommended as a source of fat. Additionally, the implementation of decision-making tools, such as the MADM method in animal science, can significantly improve management decision-making processes by reducing both time and cost. This presents a new avenue for making well-informed decisions.

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Two experiments evaluated different fat sources and levels on growth performance, carcass characteristics, and economic impact in commercial finishing pigs. In experiment 1, 2,160 pigs (337 × 1,050, PIC; initially 37.3 ± 0.93 kg) were used. Pens of pigs were blocked by initial body weight and randomly assigned to one of four dietary treatments. Three of the four dietary treatments included: 0%, 1%, and 3% choice white grease. The final treatment contained no added fat until pigs were approximately 100 kg, and then a diet containing 3% fat was fed until marketing. Experimental diets were fed over four phases and were corn-soybean meal based with 40% distillers dried grains with solubles. Overall, increasing choice white grease decreased (linear, P = 0.006) average daily feed intake (ADFI) and increased (linear, P = 0.006) G:F. Pigs fed 3% fat only during the late-finishing phase (~100 to 129 kg) had similar G:F compared to pigs fed 3% for the entire study during the late-finishing phase, and intermediate G:F overall. Increasing fat tended to increase (linear, P = 0.068) hot carcass weight (HCW). Feed cost increased (linear, P ≤ 0.005) and income over feed cost decreased (linear, P ≤ 0.041) as choice white grease increased. In Experiment 2, 2,011 pigs (PIC 1,050 × DNA 600; initially 28.3 ± 0.53 kg) were used. Pens of pigs were blocked by location in the barn and randomly assigned to one of five dietary treatments arranged in a 2 × 2 + 1 factorial with main effects of fat source (choice white grease or corn oil) and level (1% or 3% of the diet) and a control diet with no added fat. Overall, increasing fat, regardless of source, increased (linear, P < 0.001) average daily gain (ADG), decreased (linear, P = 0.013) ADFI, and increased (linear, P < 0.001) G:F. Increasing fat increased (linear, P ≤ 0.016) HCW, carcass yield, and backfat depth. There was a fat source × level interaction (P < 0.001) in carcass fat iodine value (IV), where IV increased to a greater extent in pigs fed corn oil with only a small increase in IV in pigs fed diets with choice white grease. In conclusion, these experiments suggest that increasing fat from 0% to 3%, regardless of source, produced variable responses in ADG but consistently improved G:F. Increasing fat increased HCW, carcass yield, and backfat depth, but feeding diets containing corn oil increased carcass IV. With the ingredient prices used, the improvement in growth performance did not justify the extra diet cost from increasing fat from 0% to 3% in most situations.

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BACKGROUND: There have been some reports that supplementation of fat could alleviate the negative effects of heat stress on performance in broilers. However, information regarding compensation for the adverse effects of heat stress with diets differing in fatty acids source on immune system, bone strength and carcass quality of heat-distressed broilers is limited. OBJECTIVES: The objective of this study was to investigate the effects of diets differing in fat source on performance, immune system, bone strength, and carcass quality of heat-distressed broilers. METHODS: In a completely randomized design with 4 × 2 factorial arrangement of the treatments, 320 24-day-old Ross 308 chickens, with average initial weight of 1220 ± 10 g were divided into eight treatments included sesame oil, tallow, sunflower oil and palm oil in either 22 or 32 degree of centigrade temperature. The broiler performance of each fat source-treated group was not different in this experiment and decreased significantly in heat stress condition. RESULTS: Heat stress showed a significant increase on fat, energy and ash content of thigh muscle. Tibia absolute length, width, ash and bone breaking strength were affected by fat source and increased when sesame and sunflower oil were used. Data analysis revealed that hot temperature decreased tibia weight, length, width, ash and bone breaking strength. Heat stress led to decrease of immune system parameters. CONCLUSION: Results suggest that there is no beneficial effect of broiler performance due to adding different sources of fat in broiler chicken diet under hot condition. Furthermore, the unsaturated fatty acids could improve the profile of fatty acids in thigh and enhance immune responses in broiler chickens.

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Genetic selection for rapid growth in broilers has inadvertently resulted in increased susceptibility to heat stress, particularly in male birds. Increased oxidative stress associated with hyperthermia may be reduced by avian uncoupling protein (avUCP), which has been proposed to modulate free radical production. However, the relationship between avUCP expression and current heat stress management strategies is unclear. Embryonic acclimation or thermal manipulation (TM) and dietary fat source are 2 heat stress interventions that may alter avUCP expression and oxidative stress, but the literature is inconclusive. The objective of this trial was to investigate the effect of TM and dietary fat source on avUCP gene expression and oxidative damage in the breast meat of market age broilers before and after acute heat challenge. The influence of bird sex was also evaluated as broilers exhibit a high degree of sexual dimorphism in growth and stress susceptibility. Concentration of thiobarbituric acid reactive substances (TBARS) was measured as a marker of oxidative damage. Embryonic TM occurred from incubation d 7 to 16 for 12 h daily at 39.5°C. Dietary treatments were applied during the finisher period using either poultry fat, soya oil, or olive oil supplemented at 4.5% in the diet. Acute heat stress (AHS) occurred on d 43 at 32°C for 4 h. Bird performance was decreased by TM, but no significant differences were noted between dietary fat source treatments. Neither avUCP nor TBARS concentrations were significantly influenced by TM or dietary fat source. Downregulation of avUCP was observed following AHS, concurrent with an increase in TBARS concentration. Male birds exhibited higher levels of both avUCP expression and TBARS compared to females and a significant interaction was noted for heat stress by sex, with avUCP expression being greatest in males prior to AHS. The increase in avUCP expression and TBARS concentrations in male birds may be associated with an increased susceptibility to stress arising from the increased growth rate noted for male broilers.

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Inorganic trace minerals may exacerbate lipid peroxidation, thereby impacting lipid metabolism. This study aimed to compare the effects of inorganic and coated trace minerals in diets with different fat sources, on the performance, slaughter characteristics, and antioxidant status of broiler chickens. A total of 576 21-day-old Abor Acres broiler birds were randomly divided into four dietary treatment groups in a 2 (non-coated and coated trace minerals)×2 (soybean oil and lard) factorial design. Each treatment was replicated 12 times (12 birds per replicate). The results showed that coated minerals significantly improved the average daily gain (ADG) in weight and the feed conversion ratio (P<0.01), increased serum iron, zinc, selenium, and thyroxine contents, increased the activities of glutathione peroxidase, superoxide dismutase, total antioxidant capacity, and lipoprotein lipase (P<0.05), and decreased the serum and muscle malondialdehyde (MDA) contents (P<0.01). The use of soybean oil as the fat source resulted in a high ADG in weight, a low F/G ratio, reduced serum MDA content, and drip loss of breast and leg muscles (P<0.05). In conclusion, the supplementation of coated trace minerals improved growth performance, antioxidant status, trace mineral retention within serum, and lipid metabolism. Additionally, soybean oil also improved the growth performance, antioxidant performance, and meat quality of broilers. The combination of coated trace minerals and soybean oil generated the best growth performance, antioxidant status, and meat quality characteristics.

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Behavioural and genetic evidence shows that the taste system is intimately related to the sensing of nutrients with consequences for poultry nutrition practices. A better understanding of how chickens may sense fat could provide the background for selecting feedstuffs used in poultry feeds. Acid oils have the potential to be economical and sustainable feedstuffs. These fat by-products from the edible oil refining industry possess a similar fatty acid composition to the crude oils but are richer in free fatty acids (FFA). An experiment was conducted to study the effect of FFA content and the unsaturated:saturated ratio (U:S) on dietary preferences in hens. Four fat sources were added to a basal diet at an inclusion rate of 6%, determining the experimental diets: soybean oil (SO; high U:S, 5% FFA); soybean acid oil (SA; high U:S, 50% FFA); palm oil (PO; low U:S, 5% FFA); and palm fatty acid distillate (PFAD; low U:S, 50% FFA). The experimental diets were offered in a series of double-choice tests to forty-eight Lohmann Brown laying hens housed individually in cages. Each hen was offered the ten potential binary combinations of the four diets including each diet compared to itself (referred to as four control double-choices). Feed intake was measured for two hours twice a day after one hour of fasting. Consumption was analysed as a standard preference index (% of test diet intake in comparison with the total intake). Preference values were compared to the random choice value of 50% using the Student's t-test. None of the four control comparisons differ significantly from 50% (p > 0.05), indicating that the changes in preference values observed in the other binary comparisons were related to the dietary changes associated to fat ingredients. Hens showed a feed preference for palm oil added diets over soybean oil diets (p < 0.05), with PO and PFAD being equally preferred (p < 0.05). However, in this trial the hens demonstrated a preference for SO (low %FFA) when offered in choice with SA (high %FFA) (p < 0.05). These results suggest that the degree of saturation plays an important role in dietary fat preferences: hens prefer predominantly saturated oils even when these are rich in FFA. Furthermore, when presented with a choice between predominantly unsaturated oils, hens prefer feed with a low %FFA. In conclusion, %FFA and the U:S ratio affected feed preferences in hens. The use of oils with greater preference values may give rise to greater feed palatability, enhancing feed intake at critical stages.

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Adipose tissue is an active endocrine organ secreting several adipokines, especially adiponectin, that play an important role in regulating insulin function in the body of mammals. Therefore, this study was aimed to investigate the association between abdominal fat deposit, insulin resistance, peroxisome proliferator-activated receptor gamma (PPAR-γ), and adiponectin gene (AG) expression in broiler chicks fed diets high in unsaturated fat supplemented with green tea extract (GTE). A total of 300 one-day-old female Ross 308 broiler chicks were allocated to 6 dietary treatments in a completely randomized design with a factorial arrangement of two levels of GTE (0 and 500 mg/kg diet) × three levels of fat inclusion [without fat (control group), soybean oil (SO), and tallow (Ta)]. Each treatment was replicated five times. At the end of the experiment (day 49), two chicks from each replicate weighing an average of pen weight were bled and then slaughtered for further analysis. Abdominal fat percentage, fasting concentration of blood glucose, triglyceride and insulin, glycogen reserves of breast and liver tissues, and PPAR-γ and AG expression were determined. The insulin resistance index of the Quantitative Insulin Sensitivity Check Index (QUICKI) was calculated using the fasting plasma glucose and insulin concentrations. The highest abdominal fat percentage and the lowest carcass yield were obtained in chicks fed SO-supplemented diet (P < 0.05). Chicks fed diet supplemented with SO showed the highest PPAR-γ gene expression (P < 0.05). SO-rich diets suppressed AG expression in chickens' abdominal fat tissue, and the birds fed with SO-supplemented diet showed a significant decrease in AG expression compared with the control (P < 0.05). Chicks fed diet supplemented with SO showed lower QUICKI and breast glycogen reserve compared with the control group (P < 0.05). A significant increase in blood glucose and triglyceride concentrations was observed in birds fed SO-supplemented diets (P < 0.05). AG and PPAR-γ expression increased and decreased by GTE, respectively. QUICKI tended (P = 0.09) to be greater in GTE-supplemented chicks; however, the effect of GTE supplementation on carcass yield, abdominal fat percentage, and blood insulin and glucose concentration was not significant. The findings of this study showed that SO-rich diets via increased PPAR-γ gene expression and decreased AG expression in abdominal fat may lead to insulin resistance in female broiler chicks.

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The overall objective of this study was to compare the efficacy of medium-chain fatty acids (MCFA) to other common fat sources to minimize the risk of porcine epidemic diarrhea virus (PEDV) cross-contamination in a pig bioassay. Treatments were feed with mitigants inoculated with PEDV after application and were: 1) positive control with no chemical treatment; 2) 0.325% commercially available formaldehyde-based product; 3) 1% blend of 1:1:1 caproic (C6), caprylic (C8), and capric acids (C10) and applied with an aerosolizing nozzle; 4) treatment 3 applied directly into the mixer without an aerosolizing nozzle; 5) 0.66% caproic acid; 6) 0.66% caprylic acid; 7) 0.66% capric acid; 8) 0.66% lauric acid; 9) 1% blend of 1:1 capric and lauric acids; 10) 0.3% commercially available dry C12 product; 11) 1% canola oil; 12) 1% choice white grease; 13) 2% coconut oil; 14) 1% coconut oil; 15) 2% palm kernel oil; 16) 1% palm kernel oil; 17) 1% soy oil and four analysis days (0, 1, 3, and 7 post inoculation) as well as 1 treatment of PEDV-negative feed without chemical treatment. There was a treatment × day interaction (P < 0.002) for detectable PEDV RNA. The magnitude of the increase in Ct value from d 0 to 7 was dependent upon the individual treatments. Feed treated with individual MCFA, 1% MCFA blend, or commercial-based formaldehyde had fewer (P < 0.05) detectable viral particles than all other treatments. Commercial-based formaldehyde, 1% MCFA, 0.66% caproic, 0.66% caprylic, and 0.66% capric acids had no evidence of infectivity 10-d old pig bioassay, while there was no evidence the C12 commercial product or longer chain fat sources inhibited PEDV infectivity. Interestingly, pigs given the coconut oil source with the highest composition of caprylic and capric only showed signs of infectivity on the last day of bioassay. These data suggest some MCFA have potential for reducing post feed manufacture PEDV contamination.

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A 2-factor test design was used to investigate the effect of an emulsifier (Aldo®, Lonza, America) (200 g/t) in the diet of Cherry Valley meat ducks to replace some of 2 different oils (animal fat and vegetable oil) on meat production performance, slaughter traits, and fat metabolism. The 900 healthy 18-day-old ducks were grouped into 6 treatments, each with 5 replicates and 30 meat ducks per replicate. The 2 fat sources were established as a positive control group, a negative control group (positive control group-some oil (equivalent to metabolic energy of 50 kcal/ton)), and an emulsifier group (negative control group + 200 g/ton Aldo). The results showed that addition of different fat sources in feed had no significant effect on growth performance, carcass properties, and fat metabolism of 18- to 42-day-old meat ducks (P > 0.05). Reducing the amount of oil used in the feed lowered the growth performance, carcass properties, and affected fat metabolism of meat ducks. However, in feeds with 2 fat sources, some oils were replaced by adding Aldo without affecting growth performance and carcass properties of meat ducks, and improved their fat metabolism, reduced triglycerides (TG) in serum, and increased activity of lipoprotein and hepatic lipases in liver and of pancreatic lipase. Thus, addition of Aldo to a low fat diet could improve growth performance, carcass quality, and lipid metabolism, and promote digestion and absorption of fat for meat ducks.

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A 2-yr study was conducted to evaluate the effects of level and source of fat in the diet of gestating beef cows on their prepartum performance and birth weight of progeny. Each year, 75 multiparous (≥3 calving) pregnant Angus cows were stratified by BW (663 ± 21.5 kg) and BCS (2.6 ± 0.12; 1 to 5 scale) and randomly assigned to 1 of 15 outdoor pens. Subsequently, each pen was randomly assigned to 1 of 3 (n = 5) treatments: a low-fat diet (LF; 1.4 ± 0.12% EE) consisting of grass-legume hay, barley straw, and barley grain, or 1 of 2 high-fat diets (HF; 3.3 ± 0.20% EE) that included either a canola seed (CAN) or a flaxseed (FLX) based pelleted feed. Diets were formulated to meet the requirements of pregnant beef cows during the last 2 trimesters of gestation (0.183 ± 4.8 d), adjusted for changes in environmental conditions, and offered such that each pen on average received similar daily amounts of DE (31.2 ± 2.8 Mcal/cow), CP (1.36 ± 0.13 kg/cow), and DM (12.9 ± 1.0 kg/cow). Data were analyzed as a randomized complete block design with contrasts to separate the effects of level (LF vs. HF) and source (CAN vs. FLX) of fat. After 160 d on trial, conceptus corrected-BW (CC-BW) of LF cows (708 kg) and the proportion of overconditioned cows (13.2%) were greater (P ≤ 0.04) than those of HF, with no difference (P ≥ 0.84) between CAN and FLX for CC-BW (697 kg) and proportion of overconditioned cows (3.6% vs. 2.9%). Feeding FLX diet during gestation resulted in cows with a greater (P ≤ 0.01) concentration of conjugated linolenic acid (0.12% vs. 0.05%) and n-3 (0.58% vs. 0.37%) fatty acids, and a tendency (P = 0.09) for conjugated linoleic acid concentration (1.05% vs. 0.88%) to be greater in subcutaneous adipose tissue (SCAT) when compared with cows fed the CAN diet. By the end of gestation, serum NEFA concentration of LF cows (592 µEq/L) was lower (P < 0.01) than that of HF cows, and FLX cows had greater (P < 0.01) serum NEFA concentration than CAN cows (636 vs. 961 µEq/L). Cows receiving the LF diet during gestation gave birth to lighter (P < 0.01) calves compared with those receiving the HF diets (40.2 vs. 42.9 kg), with no difference (P = 0.24) between calves born to CAN (42.4 kg) and FLX (43.3 kg) cows. In conclusion, these results suggest a partitioning of the ME in pregnant beef cows that is dependent on the type of dietary energy, resulting in heavier calves at birth for cows fed high-fat diets. Also, the type of fatty acid in the diet of gestating beef cows affected the fatty acid profile in SCAT and serum NEFA concentration.

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At present, there is limited knowledge about the possible utilization of the fat fraction derived from Hermetia illucens (HI) larvae processing. The objective of the present study was to evaluate the replacement of soybean oil with HI larvae fat in broiler finisher diet, on the quality and sensory traits of their meat. At 21 days of age, 120 male broiler chickens were randomly allocated to three experimental groups (5 replicates and 8 birds/pen): a basal control diet (C), and two groups in which either 50% or 100% of the soybean oil was replaced with HI larvae fat (the HI50 and HI100 group, respectively). At day 48, 15 birds (3 birds/pen) per group were slaughtered, and breasts and legs were excised and used for meat quality evaluations. Breast and leg physical meat quality, nutritional composition and sensory profile remained substantially unaffected by the dietary treatments. In contrast, the dietary incorporation of HI larvae fat modified the fatty acid (FA) profile of both the breast and leg meat cuts: the proportion of saturated fatty acids increased (p < 0.0001) to the detriment of the polyunsaturated (PUFA) fraction (p < 0.0001). Moreover, the meat n-6/n-3 ratio increased in the HI50 and HI100 groups compared to the C group. HI larvae fat dietary inclusion decreased the monounsaturated fatty acids in the breast (p = 0.0012) but not in the leg meat. Further research should focus on the improvement of the FA profile of the larvae through substrate modulation, or by combining HI larvae with a PUFA-rich feedstuff in feed formulations.

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Objective: This experiment aimed to investigate the effect of different sources and inclusion levels of dietary fat on productive performance and egg quality in laying hens raised under hot environmental conditions. Method: A total of 480 Hy-Line Brown laying hens at 31 wk of age were randomly allotted to 1 of 5 experimental diets. The control diet contained 2,800 kcal/kg AMEn with no fat addition. Four additional diets were prepared by adding 2.0 or 4.0% of animal fat (AF) or soybean oil (SO). Energy and nutrient concentrations were consistent among all diets. Diets were fed to hens for 4 weeks. Average daily room temperature and humidity were 26.7 ± 1.52°C and 77.4 ± 4.50%. The heat stress index was approximately 76, indicating that hens were raised under heat stress conditions. Results: Final BW was greater (p<0.05) for hens fed diets containing 2.0 or 4.0% AF than for those fed the control diet or diets containing 2.0 or 4.0% SO. The BW gain and feed intake were greater (p<0.05) for hens fed diets containing additional AF or SO than those fed the control diet. Eggshell thickness were the greatest (p<0.05) for hens fed the control diet, but the least (p<0.05) for hens fed diets containing 4.0% SO. Egg yolk color was the greatest (p<0.05) for hens fed to the control diet, but the least (p<0.05) for hens fed diets containing 4.0% SO. Conclusion: Inclusion of supplemental fat (AF and SO) in diets exhibits preventative effects on BW loss for hens raised under hot environmental conditions when energy and nutrient concentrations in diets were maintained. The effects were greater for AF than for SO. However, inclusion of supplemental fat in diets decreases eggshell thickness and egg yolk yellowness, possibly due to a reduction in Ca absorption and intake of egg yolk colorants.

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Ruminants have a unique metabolism and digestion of unsaturated fatty acids (UFA). Unlike monogastric animals, the fatty acid (FA) profile ingested by ruminants is not the same as that reaching the small intestine. The objective of this study was to evaluate whole raw soybeans (WS) in diets as a replacer for calcium salts of fatty acids (CSFA) in terms of UFA profile in the abomasal digesta of early- to mid-lactation cows. Eight Holstein cows (80 ± 20 d in milk, 22.9 ± 0.69 kg/d of milk yield, and 580 ± 20 kg of body weight; mean ± standard deviation) with ruminal and abomasal cannulas were used in a 4 × 4 Latin square experiment with 22-d periods. The experiment evaluated different fat sources rich in linoleic acid on ruminal kinetics, ruminal fermentation, FA abomasal flow, and milk FA profile of cows assigned to treatment sequences containing a control (CON), with no fat source; soybean oil, added at 2.68% of diet dry matter (DM); WS, addition of WS at 14.3% of diet DM; and CSFA, addition of CSFA at 2.68% of diet DM. Dietary fat supplementation had no effect on nutrient intake and digestibility, with the exception of ether extract. Cows fed fat sources tended to have lower milk fat concentration than those fed CON. In general, diets containing fat sources tended to decrease ruminal neutral detergent fiber digestibility in relation to CON. Cows fed WS had lower ruminal digestibility of DM and higher abomasal flow of DM in comparison to cows fed CSFA. As expected, diets containing fat supplements increased FA abomasal flow of C18:0 and total FA. Cows fed WS tended to present a higher concentration of UFA in milk when compared with those fed CSFA. This study suggests that under some circumstances, abomasal flow of UFA in early lactation cows can be increased by supplementing their diet with fat supplements rich in linoleic acid, regardless of rumen protection, with small effects on ruminal DM digestibility.

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The objective of the present study was to evaluate the effects of partial or total replacement of finisher diet soybean oil with black soldier fly (Hermethia illucens L.; HI) larva fat on the growth performance, carcass traits, blood parameters, intestinal morphology and histological features of broiler chickens. At 21 days of age, a total of 120 male broiler chickens (Ross 308) were randomly allocated to three experimental groups (five replicates and eight birds/pen). To a basal control diet (C; 68.7 g/kg as fed of soybean oil), either 50% or 100% of the soybean oil was replaced with HI larva fat (HI50 and HI100 group, respectively). Growth performance was evaluated throughout the trial. At day 48, 15 birds (three birds/pen) per group were slaughtered at a commercial abattoir. Carcass yield and proportions of carcass elements were recorded. Blood samples were taken from each slaughtered chicken for haematochemical index determination. Morphometric analyses were performed on the duodenum, jejunum and ileum. Samples of liver, spleen, thymus, bursa of fabricius, kidney and heart were submitted to histological investigations. Growth performance, carcass traits, haematochemical parameters and gut morphometric indexes were not influenced by the dietary inclusion of HI larva fat. Histopathological alterations developed in the spleen, thymus, bursa of fabricius and liver and were identified in all of the experimental groups, but HI larva fat inclusion did not significantly affect (P>0.05) the severity of the histopathological findings. The present study suggests that 50% or 100% replacement of soybean oil with HI larva fat in broiler chickens diets has no adverse effects on growth performance or blood parameters and had no beneficial effect on gut health.

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The objective of this study was to investigate the effects of dietary supplementation with various fat sources (3.8-3.9% of diet) during late pregnancy and lactation on the reproductive performance, fatty acids profile in colostrum, milk and serum of sow progeny. A total of 80 multiparous sows were randomly fed a control (adding no oil), palm oil (PO), fish oil (FO) or soybean oil (SO) supplemented diet from 90 days of pregnancy to weaning. Supplementation of FO increased litter size of weak piglets, compared with the control-fed sows (P < 0.05). Dietary FO and SO supplementation, enhanced the weaning survival rate, litter weaning weight, litter weight gain and fat content in milk (P < 0.05). The highest immunoglobulin (Ig)G and IgM levels in colostrum and milk were observed in the FO group (P < 0.05). Meanwhile, the highest concentration of C22:5 (n-3) and C22:6 (n-3) in colostrum, milk and piglet serum was observed in the FO group (P < 0.05). Taken together, dietary inclusion of FO or SO improved growth performance of nursing piglets by increasing milk fat output, and FO consumption by sows might benefit the piglets via increasing n-3 polyunsaturated fatty acid availability and immunoglobulins (IgG and IgM) secretion.

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Two separate experiments were conducted to investigate the effect of different fat sources and a supplemental exogenous emulsifier (lysophosphatidylcholine, LPC) on growth performance, antibody production titers, and ileal nutrient digestibility in broiler chicks fed with different basal diets. A total of 288 one-day-old Ross 308 chicks were used for each trial (6 dietary treatments based on 3 × 2 factorial arrangements of treatments in both trials) with 4 replicates of 12 birds each. Dietary treatments consisted of 3 different fat sources (soy oil, SO; soy free fatty acids, SFFA; and palm fat powder, PFP) and 2 LPC levels (0 and 0.1% of diet), which were evaluated with 2 different basal diets (corn/soybean meal-based diets in Exp. 1, or corn/wheat/soybean meal-based diets in Exp. 2). In Exp. 1, average daily feed intake (ADFI) was increased (P < 0.01) in birds fed PFP diets compared with those fed SO or SFFA diets. Although supplemental LPC decreased (P < 0.01) ADFI, the birds fed SFFA diets had the greater ADFI at the presence of LPC (fat source × LPC, P < 0.01). Dietary supplementation of LPC caused a 4.6% improvement (P < 0.001) in average daily weight gain (ADWG) and consequently improved (P < 0.01) feed conversion ratio (FCR). Supplemental LPC was more effective in increasing ADWG in SFFA-containing diets, resulted in a significant (P < 0.01) dietary fat source × LPC interaction. Dietary inclusion of LPC increased (P < 0.01) bursa weight and improved (P < 0.05) antibody production titers against sheep red blood cells and Newcastle disease virus during primary responses. Ileal digestibility of ether extract (EE) was improved (P < 0.05) in birds fed diets containing SO as compared with those fed PFP diets; dietary LPC supplementation, however, had no marked effect on ileal nutrient digestibility. In Exp. 2, ADWG was greater (P < 0.05) in birds fed SO-containing diets compared with PFP-supplemented broiler chicks. Furthermore, dietary supplementation with LPC improved (P < 0.05) FCR value by 2.1%. Relative thymus weight was greater (P < 0.05) in birds fed LPC-supplemented diets than those fed unsupplemented diets. Supplemental LPC increased (P < 0.05) Gumboro antibody titer, and the lowest antibody response was allotted to the birds fed PFP diets. The greatest (P < 0.05) EE digestibility was assigned to the birds fed SO and SFFA diets. The present findings showed that birds fed SFFA-containing diets had similar performance as SO birds, and supplemental LPC improved overall performance especially in SFFA-fed birds.

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The aim of the study was to compare apparent Zn absorption and Zn status of weanling rats fed diets that differed in Zn level, fat level and fat source. Semi-synthetic diets, which were about isoenergetic and contained 3% soyabean oil, were supplemented with 7 or 100 mg Zn/kg to create a mild Zn deficiency (LZ) or a high Zn supply (HZ) and with 0 (LF), 22% beef tallow (BT) or 22% sunflower oil (SF) according to a 2 × 3 factorial design of treatments. They were fed ad libitum to 6 × 8 rats for 28 days. Energy intake and growth rates were comparable among the HZ groups. Weight gains in the LZ-LF, LZ-BT and LZ-SF groups averaged 5.54, 4.95 and 4.15 g/day, and apparent Zn absorption averaged 79.4, 60.3 and 48.0 µg Zn/day, respectively, whereas faecal Zn excretion was comparable among these groups. Apparent Zn absorption, and plasma and femur Zn concentrations were lower in the high-fat groups than in the LF group, possibly due to the high cellulose content of the BT and SF diets. Plasma Zn concentrations were higher in the animals fed the BT-based than in the SF-based diets, whereas femur and soft tissue Zn concentrations were comparable among these groups. The differences between the LZ-BT and LZ-SF groups in growth rate, Zn absorption rate and Zn status were confirmed in a second experiment. The results indicate that moderately Zn-deficient diets enriched with SF in relation to BT affect Zn metabolism of weanling rats by a yet unknown mechanism.

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