Production efficiency and feeding behavior of Awassi lambs and Baladi kids fed on a high concentrate diet

Fifteen Awassi lambs and 15 Baladi kids (males, averaging 14.3 kg) were used to study the differences in feeding behavior and performance of sheep and goats fed a concentrate finishing diet (CP = 16 kg/100 kg DM, ME = 2.85 Mcal/kg DM) in a complete randomized design experiment lasting 60 days. Dry matter (DM) and organic matter (OM) intakes were significantly (P < 0.05) higher in lambs. Kids had higher (P < 0.05) apparent OM, crude protein (CP) and gross energy digestibilities. No significant (P > 0.05) differences were observed in apparent neutral detergent fiber (NDF) digestibility, eating, chewing and ruminating times. However, eating and ruminating times (as min/kg NDF intake) was significantly (P < 0.05) higher in kids. Final body weight and average daily weight gain were significantly (P < 0.05) higher in lambs while kids had significantly (P < 0.05) lower feed to gain ratio. Feed cost per kilogram weight gain for kids was better than that for lambs. Results demonstrated that Awassi lambs consumed more feed and grew faster than Baladi kids. However, kids were more efficient feed converters than lambs.     

Relative bioavailabilities of organic zinc sources with different chelation strengths for broilers fed diets with low or high phytate content

A six-day experiment was conducted to estimate the relative bioavailability values (RBV) of zinc (Zn) in three organic sources (oZn) with different chelation strengths compared to inorganic ZnSO₄ (iZn) for broilers fed a low or high phytate diet. A total of 1080, one-d-old male broiler chicks were randomly assigned to one of 18 dietary treatments (six replicates cages of ten chicks per cage) in a completely randomized design involving a 2 × 2 × 4 factorial arrangement with two levels of added phytate (0 or 10 g phytate as sodium phytate/kg), two levels of added Zn (30 or 60 mg/kg) and four Zn sources (iZn and three oZn sources) plus one low and one high phytate control treatments without Zn addition. The three oZn sources consisted of (1) Zn amino acid with weak chelation strength (ZnAA-L, formation quotient Q_f = 6.6, containing 119 g Zn/kg), (2) Zn proteinate with moderate chelation strength (ZnPRO-M, Q_f = 30.7, containing 133 g Zn/kg) or (3) Zn proteinate with strong chelation strength (ZnPRO-H, Q_f = 944.0, containing 186 g Zn/kg). Chicks were harvested at 6 days of age and pancreas metallothionein (MT) mRNA expression was used to estimate Zn RBV. Pancreas MT mRNA expression increased (P<0.01) as dietary Zn level increased. Chicks fed high phytate diets had lower (P<0.05) MT mRNA expression than chicks fed low phytate diets. Based on multiple linear regression slope ratios with ZnSO₄ set at 1.00, the RBV of ZnAA-L, ZnPRO-M and ZnPRO-H were 1.01, 1.28 and 0.70, respectively, for low phytate diets, and 1.05, 1.39 and 0.92, respectively, for high phytate diets. The slope for the oZn source with moderate chelation strength differed (P<0.05) from iZn and the other two oZn sources. The RBV of ZnAA-L, ZnPRO-M and ZnPRO-H under the high phytate diet increased by 0.04, 0.11 and 0.22, respectively, compared to those under the low phytate diet. Results indicate that the oZn sources with moderate or strong chelation strength offer partial or complete resistance to interference from high dietary phytate during digestion; and the oZn with moderate chelation strength had a greater RBV with both low and high phytate diets than iZn or oZn sources with weak or strong chelation strength.     

The effect of dietary crude protein level on intake,growth, protein retention and utilization of growing male Saanen kids

The effects of increasing dietary levels of crude protein on growth, feed intake, feed efficiency and composition of gain in male Saanen kids were studied. Four groups of four kids each initially weighing 12.1±0.18 kg and having a weight gain of 195±16 g/d were penned individually and fed for 73 to 124 days up to 25 kg of BW. They were fed chaffed wheat straw (45 g CP/kg DM) which had been molasses sprayed (10%) and pelleted concentrates containing 8.7, 11.7, 14.4 and 17.6% crude protein (CP) on DM basis, the ratio of straw to concentrate being 1:5. Kids were fed controlled to satiation in which case small amounts of the feeds were offered about five times a day as long as the kids wanted to eat. Retention of protein, fat and energy were calculated from their initial and final concentrations in the empty body homogenates of the slaughtered kids. With increasing CP level in the diet, feed intake increased from 448 to 608 g DM/d, weight gain from 94 to 181 g/d, retention of protein from 9.7 to 27.8 g/d, retention of fat from 9.6 to 19.1 g/d and feed efficiency improved from 4.79 to 3.39 kg DM/kg weight gain. Protein composition of gain increased from 103 to 154 g/kg BWG while fat (103–105 g/kg BWG) remained constant. Regression analyses showed that BWG can be optimized at 136 g CP/kg DM and protein retention at 180 g CP/kg DM, whereas, dietary nitrogen was utilized most efficiently at 120 g CP/kg DM. Extrapolated from the regression equations, maintenance N requirement of the kids at zero N-retention and at zero BWG were 0.38 and 0.16 g N/kg W^0.75, respectively. Recommended dietary CP concentrations and maintenance N requirements depend on the traits desired.     

Effect of vitamin E supplementation on arsenic induced alteration in blood biochemical profile,oxidant/antioxidant status,serum cortisol level and retention of arsenic and selenium in goats

Arsenic (As) exerts oxidative stress with depletion of body selenium in monogastric animals. But in ruminants this fact is not yet verified. Vitamin E is an effective dietary antioxidant. Thus, in this experiment, the protective effect of vitamin E against arsenic toxicity induced by sodium arsenite (60 mg As/kg diet) was investigated in goat kids. For this, 21 male kids were divided into three equal groups and fed either basal diet as such (control), or supplemented with 60 mg As/kg diet and 60 mg As/kg diet + 250 IU vitamin E/kg diet for 180 days. Vitamin E supplementation alleviated the toxic effects caused by arsenic on serum alanine aminotransferase and aspartate aminotransferase and lipid peroxidation. It also prevented the depletion of reduced glutathione content and reduction in activity of catalase, superoxide dismutase and glutathione-s-transferase in erythrocytes resulted from arsenic intoxication. The elevated levels of arsenic and reduced levels of selenium in the serum and tissues in arsenic treated animals were attenuated by vitamin E supplementation, though not completely. However, serum cortisol level was not affected by arsenic. It was concluded that arsenic exerts cortisol independent stressor mechanism and supplementation of vitamin E at a level of 250 IU/kg diet was partially effective in reducing tissue accumulation of arsenic in the body and protect the kids from oxidative stress induced by arsenic.     

Effect of partial replacement of concentrates with jackfruit (Artocarpus heterophyllus) leaves on growth performance of kids grazing on native pasture of Tripura,India

Fifteen Black Bengal kids of about 3 months of age and body weight ranging from 3.8 to 4.9 kg were randomly distributed into three groups of five. Kids grazed native pasture 8 h/d. The kids in group I received supplementary concentrate (maize 35%, mustard cake 32%, rice bran 30%, mineral mixture 2% and common salt 1%) at approximately 2% of BW. However, 25 and 50% of the concentrate was replaced with jackfruit leaves for groups II and III, respectively. Total dry matter intake (DMI) was significantly higher in groups II and III than for group I due to greater forage consumption. Digestibility of CP (P < 0.05) decreased and that of NDF increased (P < 0.01) with increasing level of jackfruit leaves in the diet. Digestibility of ADF (P < 0.01), hemi cellulose (P < 0.05) and cellulose (P < 0.01) was higher in groups II and III in comparison to group I. Ruminal pH and TVFA concentration were not significantly different among the groups; however, rumen ammonia-N concentration decreased (P < 0.01) with increased level of jackfruit leaves in the diet. Similarly, plasma urea nitrogen and blood glucose levels were also reduced (P < 0.05) with increasing level of jackfruit leaves in the diet Average daily gain (ADG) was 47.33, 45.11 and 35.56 g/d in groups I, II and III, respectively. ADG and DMI/kg gain were not adversely affected when the level of replacement was restricted to 25%; however, at the 50% of replacement both parameters were adversely affected (P < 0.05). From the results of this experiment, it was concluded that jackfruit leaves might replace 25% of the supplemental concentrate for growing kids grazing in native pasture of northeast India.     

Zinc nanoparticles potentiates thermal tolerance and cellular stress protection of Pangasius hypophthalmus reared under multiple stressors

A preliminary study was conducted to delineate the ameliorating effect of dietary zinc nanoparticles (Zn-NPs) against thermal stress in Pangasius hypophthalmus reared under concurrent exposure to lead (Pb) and elevated temperature (34 °C). Three diets were formulated such as control (no Zn-NPs), Zn-NPs 10 and 20 mg/kg diet. Two hundred and thirty four fish were randomly distributed in to six treatments groups in triplicates; such as control group (no Zn-NPs in diet and unexposed to Pb and temperature, Ctr/Ctr), control diet with concurrent exposure to Pb and temperature (Pb-T/Ctr), Zn-NPs 10 and 20 mg/kg without stressors (Zn-NPs 10 mg/kg, Zn-NPs 20 mg/kg), Zn-NPs 10 and 20 mg/kg diet with concurrent exposure to Pb and temperature (Pb-T/Zn-NPs 10 mg/kg, Pb-T/Zn-NPs 20 mg/kg). The Pb in treated water was maintained at the level of 1/21th of LC₅₀ (4 ppm) at 34 °C temperature in stressors groups. Post 60 days feeding trial, critical thermal minimum (CTmin), lethal thermal minimum (LTmin), and critical thermal maximum (CTmax), lethal thermal maximum (LTmax) and biochemical attributes on P. hypophthalmus were evaluated. The results indicated that, dietary supplementation of Zn-NPs increased the CTmin, LTmin and CTmax, LTmax in P. hypophthalmus. Positive correlations were observed between CTmin LTmin (Y = − 0.495 + 10.08x, R², 0.896) and CTmax LTmax (Y = − 0.872 + 4.43x, R², 0.940). At the end of the thermal tolerance study, oxidative stress and lipid peroxidation (LPO) were significantly reduced and neurotransmitter enzyme was significantly increased in the groups fed with Zn-NPs @ 10 mg and 20 mg/kg diet. Overall results indicated that dietary Zn-NPs can confer protection against thermal stress in P. hypophthalmus.     

Effect of dietary cobalt supplementation on plasma and rumen metabolites in Mehraban lambs

Two experiments were conducted to study the effects of different levels of dietary cobalt on performance, plasma and rumen metabolites and nutrient digestibility in Mehraban male lambs. Experiment 1: 28, 8–9-month-old lambs were randomly divided into four groups. Animals were fed a basal diet containing 0.088 mg Co/kg DM and were supplied with 0 (control), 0.25, 0.50, or 1.00 mg Co/kg DM as reagent grade CoSO₄·7H₂O. The experiment lasted for 70 days. Experiment 2: four lambs from each group in Experiment 1 were randomly allocated to the individual metabolic crates to measure the effects of dietary Co on nutrient digestibility. Final body weight, average daily gain and gain efficiency were higher (p < 0.05) in the group supplemented with 0.50 mg Co/kg DM compared to other groups. Plasma glucose and vitamin B₁₂ concentrations increased (p < 0.05) at all levels of Co supplementation on day 68 of the experiment and for vitamin B₁₂ were higher (p < 0.05) at 0.50 and 1.00 mg Co/kg DM compared to 0.25 mg Co/kg DM. There was no significant difference among treatments for TVFA and ruminal fluid pH. Digestibility of dry matter, organic matter, crude protein and neutral detergent fiber increased (p < 0.05) by Co supplementation, but did not differ among Co supplied treatments. The obtained results showed that lambs fed the control diet containing 0.088 mg Co/kg DM had a reduced appetite and gained less than the supplemented animals, suggesting that the level of 0.088 mg Co/kg DM was inadequate for normal growth of Mehraban male lambs, and a total level of 0.58 mg Co/kg DM might be optimum level for enhancing performance.     

Effects of maternal treatment of dehydroepiandrosterone (DHEA) on serum lipid profile and hepatic lipid metabolism-related gene expression in embryonic chickens

Over the last decade, much evidence emerged to suggest that alterations in maternal diets during pregnancy may irreversibly affect aspects of physiological and biochemical functions in the fetus. To explore the effects of maternal dietary treatments with dehydroepiandrosterone (DHEA) on lipid metabolism in the embryo, we investigated serum lipid profile and hepatic lipid metabolism-related gene expression in the maternal and embryonic chicken. Sixteen-week-old pullets were allocated into 3 groups (n = 30), and after laying, they were provided with a commercial diet supplemented with DHEA at 0, 20 or 100 mg/kg diet. Eggs were collected after DHEA treatment and incubated at 37.5 °C and a relative humidity of 60%. Blood and liver samples were collected from hens and embryonic chickens. DHEA treatment resulted in decreased body weight and increased relative liver weight in both maternal and embryonic chickens, while the concentrations of blood triglyceride (TG), total cholesterol (TC), low-density lipoprotein-cholesterol (LDL-C) and non-esterified fatty acid (NEFA) were significantly lower in the 20 mg DHEA/kg group as compared to the control group during embryonic development. The expression of acetyl CoA carboxylase (ACC) and carnitine palmitoyl transferase I (CPTI) gene was also reduced following treatment with 20 mg DHEA/kg at hatching. However, blood TC, and hepatic fatty acid synthase (FAS) and hydroxy methylglutaryl-CoA reductase (HMGR) gene expression were significantly up-regulated in the 100 mg DHEA/kg group during embryonic development and hatching. Overall, the results of this study indicate that maternal dietary treatment with DHEA regulates serum lipid metabolism and hepatic gene expression.     

Effect of dietary conjugated linoleic acid on serum levels of N2O5 and l-citrulline in goat kids

Forty new born male kids were allotted into two groups for the evaluation of the effects of dietary conjugated linoleic acid (CLA) on nitric oxide (NO) and l-citrulline levels in serum. The control group received no supplement CLA and the CLA group received 20 g/kg milk DM of CLA from birth to 1-month old. The kids were fed colostrum for 2 days and milk replacer from days 3 to 29. Blood samples (n = 40) were taken at 1, 8, 15, 22, and 29 days of age. N₂O₅ (nitrite + nitrate) concentration in serum ranged from 21.93 to 26.15 and 34.90 to 40.59 μmol in control and CLA kids. The l-citrulline values ranged from 0.30 to 0.40 and 15.54 to 19.81 μmol in control and CLA kids.     

The importance of pyridoxine for the impact of the dietary selenium sources on redox balance,embryo development,and reproductive performance in gilts

This study aimed to determine the effects of dietary pyridoxine and selenium (Se) on embryo development, reproductive performance and redox system in gilts. Eighty-four gilts were fed one of five diets: CONT) basal diet; MSeB₆0) CONT + 0.3 mg/kg of Na-selenite; MSeB₆10) diet 2 + 10 mg/kg of HCl-pyridoxine; OSeB₆0) CONT + 0.3 mg/kg of Se-enriched yeast; and OSeB₆10) diet 4 + 10 mg/kg of HCl-pyridoxine. Blood samples were collected for long-term (each estrus and slaughter) and peri-estrus (fourth estrus d −4 to d +3) profiles. At slaughter (gestation d 30), organs and embryos were collected. For long-term and peri-estrus profiles, Se level and source affected (P < 0.01) blood Se concentration whereas B₆ level increased (P < 0.01) erythrocyte pyridoxal-5-phosphate concentration. A B₆ level (P < 0.05) effect was observed on long-term plasma Se-dependent glutathione peroxidase (Se-GPX) activity whereas peri-estrus Se-GPX was minimum on d −1 (P < 0.01). Selenium level increased sows’ organs and embryo Se concentration (P < 0.01). Selenium source tended to enhance embryo Se content (P = 0.06). Within-litter embryo Se content was increased by B₆ level (P < 0.01). Selenium level tended to affect Se-GPX and total GPX activities in organs mitochondria (P = 0.09 and 0.07, respectively). Selenium source affected kidney ATP synthesis (P = 0.05). In conclusion, B₆ level affected the Se-GPX activity on a long-term basis, whereas the basal level of Se was adequate during the peri-estrus period. Embryo quality was not improved by dietary Se, and B₆ impaired within-litter homogeneity.     

Dietary supplementation of green synthesized manganese-oxide nanoparticles and its effect on growth performance,muscle composition and digestive enzyme activities of the giant freshwater prawn Macrobrachium rosenbergii

The green synthesized Mn₃O₄ nanoparticles (manganese-oxide nanoparticles) using Ananas comosus (L.) peel extract was characterized by various techniques. HR-SEM photograph showed that manganese-oxide nanoparticles (Mn-oxide NPs) were spherical in shape, with an average size of 40–50 nm. The Zeta potential revealed the surface charge of Mn-oxide NPs to be negative. Further, the Mn-oxide NPs were dietary supplemented for freshwater prawn Macrobrachium rosenbergii. The experimental basal diets were supplemented with Mn-oxide NPs at the rates of 0 (control), 3.0, 6.0, 9.0, 12, 15 and 18 mg/kg dry feed weight. The as-supplemented Mn-oxide NPs were fed in M. rosenbergii for a period of 90 days. The experimental study demonstrated that prawns fed with diet supplemented with 3–18 mg Mn-oxide NPs/kg shows enhanced (P < 0.05) growth performance, including final weight and weight gain (WG). Significant differences (P < 0.05) in feed conversion ratio (FCR) were observed in prawn fed with different diets. Additionally, prawns fed with 3.0–18 mg/kg Mn-oxide NPs supplemented diets achieved significant (P < 0.05) improvement in growth performance, digestive enzyme activities and muscle biochemical compositions, while, the prawns fed with 16 mg/kg of Mn-oxide NPs showed enhanced performance. Prawns fed on diet supplemented with 16 mg/kg Mn-oxide NPs showed significantly (P < 0.05) higher total protein level. The antioxidants enzymatic activity (SOD and CAT) metabolic enzymes status in muscle and hepatopancreas showed no significant (P > 0.05) alterations in prawns fed with 3.0–18 mg/kg of Mn-oxide NPs supplemented diets. Consequently, the present work proposed that 16 mg/kg of Mn-oxide NPs could be supplemented for flexible enhanced survival, growth and production of M. rosenbergii. Therefore, the data of the present study recommend the addition of 16 mg/kg of Mn-oxide NPs diet to developed prawn growth and antioxidant defense system.     

Growth performance and starch utilization in common carp (Cyprinus carpio L.) in response to dietary chromium chloride supplementation

A nutrition trial was conducted on juvenile common carp (Cyprinus carpio), initial mean body weight 15 ± 0.4 g within a controlled facility at 25 ± 0.5 °C. Six diets containing various levels of supplementary Cr (0, 0.2, 0.5, 1.0, 1.5, and 2.0) mg Cr/kg of diet as Cr chloride hexahydrate were fed to carp for a period of 10 weeks. Lower growth performance was observed in fish fed on the control diet and the diet supplemented with the highest level of Cr (2.0 mg Cr/kg). Although fish fed 0.5 mg Cr/kg showed the best growth performance, this was not significantly different (P > 0.05) from fish fed 1.0 mg Cr/kg. The regression of plasma glucose concentration was linear (R² = 0.97 and P value = 0.001) as the Cr content of the diet increased (up to 1.5 mg Cr/kg).Cr carcass content was elevated with an increasing level of dietary Cr supplementation up to 1.5 mg Cr/kg; but fish fed on the diet supplemented with the highest level of Cr (2.0 mg Cr/kg) showed a decrease in Cr carcass content.Histological examination to evaluate the impact of different Cr supplementation on liver and gut tissues showed notable changes. The higher level of Cr (2.0 mg Cr/kg) in the diet gave rise to elevated hepatocyte vacuolization and changes in gut tissue morphology.It appeared that Cr chloride significantly improved growth within a defined range (0.2–1.5) mg Cr/kg without any negative impact, while 2.0 mg Cr/kg in carp diet seems to be the threshold for the initiation of toxicity.     

Effect of melengestrol acetate (MGA) treatment or temporary kid removal on reproductive efficiency in meat goats

The use of melengestrol acetate (MGA; Summer) or temporary kid removal (4 weeks postpartum; Fall) for inducing/synchronizing estrus was evaluated in goats. In the first trial, 47 does were group-fed a commercial diet to provide 0.25 mg MGA/doe daily (n = 25) or a control diet (n = 22) for a period of 10 days. Twenty-five of the does lambing in the fall from this experiment were used in a second experiment. Beginning on day 28.1 ± 0.8 of lactation, kids from 13 does (kid removal) were removed from their dams for 2 days while kids from the remaining 12 does (control) remained with the dams. Mature bucks wearing marking harnesses were introduced for mating at the end of MGA treatment (Experiment 1) or at the time of kid removal (Experiment 2). Does fed MGA were mated approximately 2.1 days earlier (P < 0.05) than control does. The percentage of does mated (84% versus 100%), pregnancy rate (58% versus 90%), and kidding rate (58% versus 90%) was lower (P < 0.05) for the MGA-treated versus the control does, respectively. In Experiment 2, does with kids removed were mated approximately 1.3 days earlier than the control does, but the mean weaning weight of the kids (11.0 ± 0.4 kg for both treatments) was not influenced by treatment. The mean pregnancy rate, kidding rate, kid birth weight, or kid weaning weight was not influenced by treatment and averaged 73.0 and 79.0%, 3.3 ± 0.2 and 16.8 ± 0.7 kg for both treatments, respectively. Overall, although not necessary for mating, a decreased time to first mating and increased synchrony of estrus followed both MGA treatment or temporary kid removal. This may be implemented if improved estrus synchrony is desired. However, more research is needed to overcome the decreased fertility recorded following MGA use.     

Interaction of dietary zinc and growth implants on weight gain,carcass traits and zinc in tissues of growing beef steers and heifers

In two separate studies, 60 beef heifers (379 kg BW) and 60 beef steers (348 kg BW) were randomly assigned to six treatments in 2×3 factorial arrangements. The treatments were with or without Synovex^® implants combined with either a control diet or diets supplemented with 200 ppm Zn from ZnSO₄ or zinc methionine (Zn-Met). Near the mid-point of the feeding periods, cattle were vaccinated with a modified live virus and subsequent titers and concentrations of immunoglobulin G (IgG) were measured. Liver and blood samples were obtained 1 week prior to the start of the experiments and at intervals during the experiments. In experiment 1, average daily gains of beef heifers were (P<0.05) affected by the interaction of implant and source of dietary Zn. Compared to control and ZnSO₄ treatments, supplementation with Zn-Met increased (P<0.05) the concentration of Zn in serum. Antibody titers and concentrations of IgG in serum were highest (P<0.05) in heifers fed ZnSO₄ compared to heifers fed the control or Zn-Met supplemented diets. The Synovex-H^® implant reduced the concentrations of Zn and Cu in liver. In experiment 2, Synovex-S^® implants improved (P<0.05) weight gains of steers supplemented with 200 ppm dietary Zn from ZnSO₄ compared to non-implanted steers. However, the implant had no effect when Zn-Met was the dietary Zn source. The implant increased (P<0.05) concentrations of Zn in liver of steers supplemented with 200 ppm dietary Zn and reduced Zn in liver of steers fed the control diet. Implanted steers had higher (P<0.05) Cu status and IgG concentrations in serum than non-implanted steers. Steers supplemented with either ZnSO₄ or Zn-Met had greater (P<0.05) concentrations of Zn in liver and plasma than steers fed the control diet. These results indicate both the level and source of Zn supplementation in diets of feedlot cattle affect their response to growth implants.     

Effects of Supplemental Copper on the Serum Lipid Profile,Meat Quality,and Carcass Composition of Goat Kids

To evaluate the effects of copper (Cu) supplementation on the serum lipid profile, meat quality, and carcass composition of goat kids, thirty-five 3–4-month-old Jian Yang big-eared goat kids (BW 20.3?±?0.6 kg) were randomly assigned to one of seven dietary Cu treatments (n?=?5/treatment). The dietary Cu concentrations were: (1) control (no supplemental Cu), (2) 20 mg, (3) 40 mg, (4) 80 mg, (5) 160 mg, (6) 320 mg, and (7) 640 mg of supplemental Cu/kg dry matter (DM). Copper was supplemented as CuSO₄.5H₂O (25.2 % Cu). The goats were fed a high-concentrate basal diet with the different concentrations of supplemental Cu/kg DM for 96 days. The serum lipid profile was determined on day 51 and day 96. Meat quality and carcass composition of longissimus dorsi muscle were measured after the goats were slaughtered at 96 days. Serum total cholesterol, triglycerides, high density lipoprotein-cholesterol (HDL-C), and low density lipoprotein-cholesterol (LDL-C) were not affected by treatment (P?>?0.18). No differences were observed in drip loss, cooking loss, a* (redness/greenness) and b* (yellowness/blueness) values (P?>?0.17); however, the 24-h pH value (linear; P?=?0.0009) and L* (brightness) value (linear; P?=?0.0128) decreased, and shear force increased (linear; P?=?0.0005) as Cu supplementation increased. The intramuscular fat (%) increased (linear; P?=?0.001) as supplemental Cu increased. No differences (P?>?0.21) in the moisture, crude protein, and ash (%) were observed. Results of this study indicate that supplemental Cu does not modify the serum lipid profile; however, it can impact intramuscular fat content and the meat quality of goat kids.     

The effect of benzoic acid concentration on nitrogen metabolism,manure ammonia and odour emissions in finishing pigs

A complete randomised block design experiment was conducted to investigate the effects of benzoic acid inclusion level on nitrogen (N) metabolism, and manure ammonia (NH₃) and odour emissions in finishing pigs. Sixteen boars (64 kg live weight ± 1.5 kg) were assigned to one of four dietary treatments (T) varying in benzoic acid concentration: (T1) 0 g benzoic acid/kg (as fed); (T2) 10 g benzoic acid/kg; (T3) 20 g benzoic acid/kg; (T4) 30 g benzoic acid/kg. Animals were housed in individual metabolism crates and feed was provided ad libitum. All diets were formulated to have similar concentration of digestible energy and ileal digestible lysine with benzoic acid replacing wheat in the diet. There was a linear decrease in NH₃ emission (P<0.001), as the dietary benzoic acid concentration increased (141.4 mg/g versus 40.5 mg/g N intake (S.E.M. 12.1) over the 240-h storage period). However, there was no effect (P>0.05) of benzoic acid on odour concentration. Urinary nitrogen (N) excretion, total N excretion and the urinary:faecal N ratio were linearly reduced (P<0.05) with increasing benzoic acid inclusion. Furthermore, N retention increased linearly (P<0.05) as benzoic acid concentration increased from 0 g/kg to 30 g/kg in the diet. In conclusion, the inclusion of benzoic acid in the diet of finishing pigs has the potential to reduce total and urinary N excretion and the urinary to faecal N ratio. This was mirrored by reductions in manure NH₃ emissions in the benzoic acid supplemented treatments.     

l-Lysine supplementation does not affect the bioavailability of copper or iron in rats

l-lysine (Lys) is an essential amino acid that is added to foods and dietary supplements. Lys may interact with mineral nutrients and affect their metabolism. This study examined the effect of dietary Lys supplementation on the bioavailability of copper (Cu) and iron (Fe). Weanling male Sprague-Dawley rats were fed one of five diets (20% casein) for 4 weeks containing normal Cu and Fe (control) or low Cu or Fe without (LCu, LFe) or with (LCu + Lys, LFe + Lys) addition of 1.5% Lys. Final body weights, body weight gains and food consumption of the rats did not differ (P ≥ 0.05) among diet groups. Rats fed the low Cu or Fe diets showed changes in nutritional biomarkers compared to control rats, demonstrating reduced Cu and Fe status, respectively. Hematological parameters, serum ceruloplasmin activity and Cu and Fe concentrations in serum, liver, kidney and intestinal mucosa were unaffected (P ≥ 0.05) by Lys supplementation. These results indicate that in the context of an adequate protein diet, Lys supplementation at a relatively high level does not affect Cu or Fe bioavailability in rats.     

Efficiency of energy use for pregnancy by meat goat does with different litter size

Twenty-four Boer × Spanish does (3 years of age, having kidded once previously and with an initial BW of 42.7 ± 1.2 kg) were used to determine the efficiency of ME utilization for pregnancy (k_preg). Six does were nonpregnant and, based on ultrasound determination on day 45 of gestation, six had a litter size (LS) of 1, 2, and 3. However, only 10 of the pregnant does delivered the expected number of kids (3, 4, and 3 with LS of 1, 2, and 3, respectively). Does were fed a diet of approximately 50% concentrate in accordance with assumed maintenance plus pregnancy energy requirements based on estimated nonpregnancy tissue BW and LS. Recovered energy (RE) was determined by subtraction of energy expenditure (EE; respiration calorimetry) near days 80, 100, 120, and 140 of gestation from ME intake (MEI). RE was assumed attributable to pregnancy tissues (fetus, fetal fluids and membranes, uterus, and mammary gland), and ME used for pregnancy (ME_preg) was estimated by subtracting ME_m determined with nonpregnant goats from MEI by those pregnant. For does with actual LS equal to that expected, the no-intercept equation for the regression of RE against ME_preg was: RE = ME_preg × 0.252 (S.E. = 0.030; R² = 0.64), indicating a k_preg of 25%. A regression including LS (1 versus 2 or 3) suggested greater k_preg for LS of 1 (40.2 ± 5.6%) versus 2 or 3 (20.5 ± 3.2%). Regressions for goats with LS different from expected suggested positive effects of use of energy mobilized from nonpregnancy tissues on k_preg and of use of dietary ME for energy accretion in nonpregnancy tissues on the efficiency of whole body ME utilization. In conclusion, the average efficiency of ME use for pregnancy regardless of LS in goats was near 25%, which when considering the expected proportion of all pregnancy tissues attributable to fetal or conceptus tissues implies an energy requirement for pregnancy of goats similar to common recommendations for sheep and cattle.     

Biochemical and histological impact of Vernonia amygdalina supplemented diet in obese rats

This study was carried out to evaluate the anti-obesity effect of Vernonia amygdalina Del. (VA) supplemented diet. VA leaf powder was fed at 5% and 15% to diet-induced obese rats for 4 weeks and its effect compared with orlistat (5.14 mg/kg p.o.), an anti-obesity drug. Food intake, body and organ weights, total body fat, some lipid components and amino transaminase activities in serum, hepatocytes and brain; as well as serum glucose, were measured during or at end of the study. Result showed respective decrease of 12.78% and 38.51% in body weight gain, of VA fed rats against 17.45% of orlistat at end of study (P < 0.05); but with no effect on food intake. Total body fat was lowered by 28.04% and 30.02% vs. obese control rats (CDC) (P < 0.05). Furthermore, serum triacylglycerol (TG), serum and brain total cholesterol (TCHOL), were down regulated at 15% VA supplementation (P < 0.05). Serum glucose which increased in obese rats by 46.26% (P < 0.05) vs. NC, indicating intolerance, was restored by VA (38.75% and 34.65%) and orlistat (31.80%) vs. CDC (P < 0.05). VA diet also exerted hepato-protection, via lowering serum alanine amino transaminase (ALT) (41.35% and 27.13%) and aspartate amino transaminase (AST) (17.09% and 43.21%) activities (P < 0.05). Orlistat had no effect on these enzymes. Histology of adipose tissue corroborated the changes on total body fat. We concluded that, diet supplemented with VA can attenuate dietary obesity as well as ameliorates the potential risks of hepato-toxicity and glucose intolerance associated with obesity.     

Dietary inclusion of raw faba bean instead of soybean meal and enzyme supplementation in laying hens: Effect on performance and egg quality

An experiment was conducted with 160 Hisex Brown laying hens to evaluate the effect of different inclusion levels of faba bean (FB) and enzyme supplementation on productive performance and egg quality parameters. The experimental diets consisted of five levels of FB: 0% (control), 25%, 50%, 75% and 100%, substituting soybean meal (SBM), and two levels of enzyme supplementation (0 or 250 mg/kg). Each dietary treatment was assigned to four replicate groups and the experiment lasted 22 weeks. A positive relationship (P < 0.05) was found between FB inclusion and body weight (BW) change of hens when compared to those of the control treatment. Enzyme supplementation significantly affected the final hens’ BW. Feed consumption (FC) of hens was statistically increased with increasing FB level up to 50%. Supplementing dietary enzyme mixture at 250 mg/kg led to improvement in FC at all studied ages (P < 0.05). Inclusion of 25% or 50% FB in diets had no adverse effects on feed conversion ratio (FCR) compared to the higher FB inclusion levels (75% or 100%). Egg weight (EW), egg number (EN) and egg mass (EM) were significantly (P < 0.05) influenced by FB inclusion in diet during the entire experimental periods, except for EN and EM at 20–24 weeks of age. Egg productive parameters were not influenced by enzyme mixture supplementation (P > 0.05). The main effect of FB levels replacing for SBM affected (P < 0.05) yolk and shell percentages, yolk index, yolk to albumen ratio, shell thickness and egg shape index. It can be concluded that FB and enzyme supplementation could be included in hens diet at less than 50% instead of SBM to support egg productive performance, however higher raw FB levels negatively affected egg production indices and quality.