Effects of dietary probiotic inclusion on performance, eggshell quality, cecal microflora composition, and tibia traits of laying hens in the late phase of production

Ninety-six White laying hens (64 weeks old) were used to investigate the effect of dietary inclusion of Bacillus subtilis on performance and eggshell quality. Hens were randomly distributed into three treatment groups and fed basal diet (control), basal diet plus 0.5 g/kg B. subtilis (Probiotic-0.5), or basal diet plus 1 g/kg B. subtilis (Probiotic-1) for 10 weeks. Probiotic-1 group exhibited the maximum (P?<?0.05) increase in egg production, egg weight, egg mass, eggshell weight, and eggshell thickness, compared with Probiotic-0.5 and the control groups. During the last week of the study, eggshell densities were 94.9, 88.7, and 65.6 mg/cm² in Probiotic-1, Probiotic-0.5, and the control group, respectively. The average unmarketable eggs were 1.3 %, 2.2 %, and 6.4 % in Probiotic-1, Probiotic-0.5, and the control group, respectively. Tibia weight, density, and ash content increased significantly. The average time required by B. subtilis to establish a significant effect was 3 weeks for Probiotic-1and 6 weeks for Probiotic-5. B. subtilis improved gut microflora balance, which has the potential to improve gut health and absorption efficiency. It should be possible to improve egg performance and eggshell quality of aged laying hens by dietary inclusion of B. subtilis, which will be of importance for farmers.     

Influence of varying dietary electrolyte balance on broiler performance under tropical summer conditions

A 6‐week feeding trial was conducted to determine the effects of varying dietary electrolyte balance (DEB) on growth performance and physiological responses in broiler chicks reared during hot summer months (26.1–37.5 °C). The average minimum and maximum room temperatures recorded from 14 to 42 days of age were 26.1 and 37.5 °C, respectively, with relative humidity ranging from 51% to 55%. Five DEB treatments supplying 0, 50, 150, 250 and 350 (Na⁺+K⁺–Cl^?) mEq/kg of diet were prepared by adding NaHCO₃ and/or NH₄Cl to basal diet that contained 185 mEq/kg from 1 to 28 days and 172 mEq/kg from 29 to 42 days. These DEB diets were randomly offered to six experimental units of 20 chicks each. Improved 42‐day body weight gain (BWG), feed:gain (F:G) and reduced mortality was noted with DEB 50, 150 and 250 mEq/kg compared to DEB 0 and 350 mEq/kg. A quadratic effect of increasing DEB level was observed on BWG and F:G, whereas the effect was linear for feed intake, water intake and litter moisture. The DEB 50, 150 and 250 maintained better blood pH, pCO₂ and HCO₃ concentrations during acute heat stress periods than that of 0 and 350. The blood heterophil and lymphocyte percent as well as heterophil:lymphocyte were remained unaffected. The lowest DEB (0 mEq/kg) diet reduced the feed intake and promoted metabolic acidosis. At 350 mEq/kg DEB, water intake and metabolic alkalosis were promoted probably due to high levels of dietary NaHCO₃. The study concluded that overall better performance was recorded with DEB 50, 150 and 250 mEq/kg. These results indicated that single optimal DEB value could not be recommended to combat heat stress in broilers.     

Effects of dietary electrolyte balance and addition of electrolyte–betaine supplements in feed or water on performance,acid–base balance and water retention in heat-stressed broilers

1. The effects of dietary electrolyte balance (DEB) and electrolyte–betaine (El-Be) supplements on heat-stressed broiler performance, acid–base balance and water retention were evaluated during the period 31–40 d of age in a 2 × 3 factorial arrangement of treatments.

2. A total of 240 broilers were assigned to 6 treatment groups each with 8 replicates of 5 birds per cage and were exposed to cyclic high temperature (32 – 24 ± 1°C). Birds were provided with diets having DEB of either 180 or 220 mEq/kg. El-Be supplements were either added to the diet, water or not added to either of them to complete the array of 6 treatment groups.

3. An additional 80 birds were kept at thermoneutral temperature (20 ± 1°C) and were provided with tap water and diets with DEB of either 180 or 220 mEq/kg to serve as negative controls.

4. Exposure to high temperature depressed growth performance, increased rectal temperature and decreased potassium (K⁺) retention. In high-temperature room, birds fed on diets with DEB of 220 mEq/kg tended to increase BW from 35–40 d of age. However, at thermoneutral temperature, broilers fed on diets with DEB of 220 mEq/kg increased K⁺ retention.

5. Adding El-Be supplements in feed or water improved feed conversion ratio (FCR), enhanced water consumption and increased K⁺ and sodium (Na⁺) retention.

6. Interactions between DEB and El-Be supplements tended to affect body weight gain and FCR during the periods 35–40 and 31–40 d of age, respectively. It is suggested that when using a diet with DEB of 180 mEq/kg, adding the El-Be supplements in drinking water was more beneficial than in feed. Adding the supplements in feed or water was equally useful when using DEB of 220 mEq/kg.

     

Concentrate supplementations of grazing pregnant Kalahari Red goats: Effects on pregnancy variables,reproductive performance,birth types and weight of kids

A study was conducted for 22 weeks to determine the effects of concentrate supplementations at three crude protein (CP) levels, i.e. low protein diet—LPD 12.42% CP (124.93 g day^?1); medium protein diet—MPD 14.18% CP (145.87 g day^?1) and high protein diet—HPD 16.35% CP (168.19 g day^?1) on some pregnancy variables, reproductive performance, birth types and weight of kids kidded by pregnant Kalahari Red goats grazed on Chloris gayana. Thirty-three matured Kalahari Red goats of first parity within age range of 2 to 2¹/₂ years with an average body weight of 38.10 ± 1.13 kg were randomly allotted to the diets with 11 goats per treatment. Data obtained were subjected to analysis of variance in a completely randomised design. It was observed that goats fed HPD had the highest (p < 0.05) values for products of pregnancy (10.35 kg) taken within 24hour before kidding and foetal growth rate (88.37 g day^?1) during pregnancy. Goats fed MPD had the lowest values (p < 0.05) of 9.28 kg and 80.07 g day^?1 for each of the respective parameters. Afterbirth weight was also the highest and lowest (p < 0.05) for goats supplemented with HPD (3.38 kg) and MPD (3.04 kg), respectively. On the other hand, MPD-supplemented goats had the highest values (p < 0.05) for litter size (2.14) and litter weight (6.80 kg) at birth, the value which was the least for HPD supplementation. From the results obtained from this study, it could be concluded that concentrate diet supplementation with 14.18% CP improved litter size and weight at birth with resultant reduction in weights of pregnancy variables of pregnant Kalahari Red goats grazed on Rhodes grass.     

Methane emissions from river buffaloes fed on green fodders in relation to the nutriet intake and digestibility

Fifteen male Murrah buffalo calves (15–18 months, 227.98?±?4.44 kg body weight) were distributed randomly in to three equal groups and fed solely on either berseem (G₁), oats (G₂), or chicory fodder (G₃). A digestibility trial followed by methane measurement using SF₆ tracer technique was conducted. No significant difference was observed in nutrient intake; however, crude protein (CP) intake was lower in G₂ (0.35 kg) than G₁ (0.7) and in G₃ (0.71) and non-fibrous carbohydrates (NFC), and neutral detergent insoluble CP (NDICP) intake was significantly (p?<?0.05) higher in G₃ (1.54 and 0.31 kg) followed by G₂ (1.27 and 0.2 kg) and G₁ (1.06 and 0.18 kg). The digestible dry matter, organic matter, neutral detergent fiber, and ether extract intake was similar in all the groups, whereas the digestible CP and NFC intake was lower in G₂ compared to G₁ and G₃. Chicory- and berseem-fed groups emitted 12.2 and 5.2 % less methane than oats-fed group. However, no significant difference was observed in the absolute methane loss and methane loss as percentage of energy intake (p?>?0.05) among the groups. There was positive correlation between nutrient intake and total methane production. However, an inverse relationship was observed between total digestible carbohydrate intake and methane production (g/kg dry matter intake). The following regression equations were developed to estimate methane production: methane (g/kg BW) = 128.8553 + (167.7456 × dNDFI) + (216.32 × dCPI) ? (40.3313 × dNFCI) and methane (g/d) = ?1.7494 + (41.42 × NDFI) + (39.8686 × CPI) + (0.5197 × NFCI).     

Practice on improving fattening local cattle production in Vietnam by increasing crude protein level in concentrate and concentrate level

Two experiments were conducted to determine the effects of crude protein (CP) level in concentrate (experiment 1) and concentrate level (experiment 2) on feed intake, nutrient digestibility, nitrogen (N) retention, ruminal pH and NH₃-N concentration and average daily gain (ADG) of Vietnamese local fattening cattle. Animals (24 cattle, initial live weight (LW) 150.3?±?11.8 kg in experiment 1 and 145.1?±?9.8 kg in experiment 2) were allotted based on LW to one of four treatments in a randomised complete block design. In experiment 1, concentrate with four levels of CP (10, 13, 16 and 19 %) was fed at 1.5 % of LW. In experiment 2, concentrate was fed at 1.0, 1.4, 1.8 and 2.2 % of LW. In both experiments, roughage was 5 kg/day native grass and ad libitum rice straw (fresh basis). Results showed that the CP level in concentrate significantly affected dry matter (DM) intake (P?<?0.05), N retention, ADG and ruminal NH₃-N concentration (P?<?0.01), but it had no significant effect on DM, organic matter (OM) and neutral detergent fibre (NDF) digestibility (P?>?0.05), whereas CP digestibility increased (P?<?0.001) along with the CP level. DM intake, N retention and ADG increased (P?<?0.001) linearly with concentrate intake. DM and CP digestibility were not significantly affected by concentrate intake (P?>?0.05). OM digestibility and NH₃-N concentration increased linearly (P?<?0.05), whereas NDF digestibility and ruminal pH declined linearly with increased concentrate consumption (P?<?0.01). These results indicate that 16 % CP in concentrate and feeding concentrate at the rate of 2.2 % of LW are recommendable for fattening local cattle in Vietnam.     

Effects of nutrition level of concentrate-based diets on growth performance and carcass characteristics of Hainan black goats

This study assessed the effects of different nutrition levels of diets on growth performance and carcass characteristics of Hainan black goat. Twenty-four goats were divided into six diet treatments, which consisted of two levels of crude protein (CP; 15 and 17 %) and three levels of digestive energy (DE; 11.72, 12.55, and 13.39 MJ/kg). The results revealed that 17 % CP significantly (P?<?0.05) increased ADG and improved FCR compared with 15 % CP. Therefore, the CP levels of diet affected growth performance. CP and DE levels in the diet had no significant effects (P?>?0.05) on carcass characteristics of the goats. The mRNA expression levels of insulin-like growth factor 1 in muscle tissues increased with increasing CP and DE levels (P?<?0.05).     

Influence of replacing corn silage with barley silage in the diets of buffalo cows on milk yield and quality

A 150-day trial was carried out on 40 Italian Mediterranean buffalo cows that, immediately after calving, were equally divided into two homogeneous groups (M and O) based on the number of calving events and previous milk yield. The animals were fed (16 kg dry matter (DM)/head) two isoenergy/isoprotein diets (NEl: 6.39 MJ/kg DM; 15.4 CP% DM), composed of corn (diet M) or barley silage (diet O) concentrate, alfalfa hay, and a vitamin-mineral supplement. The fermentation characteristics of both silage diets were evaluated by an in vitro gas production technique, and their nutritional values were calculated as follows: NEl (MJ/kg DM) = 0.54 + 0.0959 GP + 0.0038 CP + 0.0001733 CP², where GP is the gas production after 24 h of incubation (ml/200 mg DM) and CP is the protein content of silage (g/kg DM). The nutritional values of the silages were slightly different (4.16 vs. 4.14 MJ/kg DM for M and O, respectively) likely due to the high content of hemicellulose in the O diet (22.0 vs. 16.9%). Average milk yield did not differ between the groups; instead, milk fat (8.39 vs. 9.06%; P < 0.01) and protein (4.41 vs. 4.60%; P < 0.01) levels were significantly higher in the O group. The results elicit great interest in southern Italy where corn cultivation is adversely affected by the high cost of irrigation.

     

Effect of palm kernel cake as protein source in a concentrate diet on intake, digestibility and live weight gain of goats fed Napier grass

The effects of palm kernel cake (PKC) as a protein source in a concentrate diet (comprising 35 % crushed maize, 30 % rice bran, 32 % PKC, 2 % vitamin mineral premix and 1 % salt) were examined on intake, live weight (LW) gain and digestibility in female goats (average LW of 12.4?±?2.6 kg). Four goats were randomly allocated to each of the four treatment diets: (a) Napier grass (Pennisetum purpureum) offered ad libitum (T1), (b) T1 + concentrate at 0.5 % of LW (T2), (c) T1 + concentrate at 1.0 % of LW (T3) and (d) T1 + concentrate at 2.0 % of LW (T4). A 7-day digestibility trial and an 82-day growth experiment were conducted. No differences were observed among diets for intakes of roughage dry matter (DM), total DM, organic matter (OM) and neutral detergent fibre (NDF). The crude protein (CP) intake increased (P?<?0.05) as the level of concentrate in the diets increased. Goats fed the T2, T3 and T4 diets gained 10.2, 34.1 and 52.5 g/head/day, respectively, while the control group (T1) lost weight (?12.7 g/head/day). The apparent digestibilities of DM, OM and CP were similar (P?>?0.05) among treatments. The digestibility of dietary NDF decreased (P?<?0.05) with increasing levels of concentrate, but there was no significant (P?>?0.05) difference between T2 and T3 diets. Supplementing a basal diet of Napier grass with PKC-based concentrate improved CP intake and LW gain. The PKC-based concentrate diet can therefore be exploited for the use of local feed resources for goat production; however, further research is required to achieve the best growth response.     

Effects of supplementing Leucaena leucocephala and conserved forages from natural pasture on the performance of grazing calves

Twelve white Fulani × N'dama cross-bred calves weighing 83.79?±?1.16 kg were used in an 84-day experiment to investigate the utilization of forage resources from natural grazing land. The experimental diets were sole grazing, grazing + hay, grazing + silage and grazing + Leucaena leucocephala leaves. The calves were divided into four groups of three animals each and were randomly assigned to the four experimental diets. Crude protein (CP) contents of the forages ranged from 59 to 171 g/kg dry matter (DM). Neutral detergent fibre (NDF) and acid detergent fibre (ADF) contents of the forages ranged from 560 to 705 g/kg DM and 363 to 440 g/kg DM, respectively. Significantly (P?<?0.05) higher values in mineral contents (Ca, K, P and Mg) were recorded for L. leucocephala leaves compared to other forage resources. Variations (P?<?0.05) were observed in the average daily gain. Animals on grazing + L. leucocephala leaves diet had the highest (113 g/day) average daily gain, while those on sole grazing showed the least value (26.2 g/day). Packed cell volume (PCV), total serum protein, urea and calcium concentration showed significant differences (P?<?0.05). Effective utilization of forage resources from the natural pasture by the calves was attained on supplementation with conserved forages and L. leucocephala leaves without any deleterious effects on the haematological and serum parameters.     

Production Performance and Egg Quality of Hy-Line W36 Laying Hens Fed Reduced-Protein Diets at a Constant Total Sulfur Amino Acid:Lysine Ratio

Two hundred eight 20-wk-old Hy-Line W36 hens at a 5% production rate were assigned to 2 dietary treatments varying in CP content. Each treatment consisted of 13 replicates of 8 hens. Dietary CP levels of the control diet were 17.8, 19.9, 18.5, and 15.5% during the periods of 1) a 5 to 50% production rate, 2) a 50% production rate until mo 7, 3) mo 8 to 10 of the production cycle, and 4) mo 10 to 12 of the production cycle, respectively. The respective CP levels of the reduced-CP diet fed during these phases were 16.3, 18.4, 17.0, and 13.9%. The reduced-CP diets had dietary CP levels approximately 1.5 percentage units lower than their control counterparts. Dietary treatments met the minimal requirements for amino acids recommended by NRC (1994). Hen-day egg production, egg mass, and FCR were maintained well on the low-protein diet during the first 8 mo of production but tended to be impaired thereafter. In mo 10 and 11 of the laying period, egg mass was significantly (P < 0.05) reduced and FCR was significantly (P < 0.05) impaired on the reduced-CP diet compared with the control diet. Egg weight, eggshell thickness, eggshell breaking strength, and albumen height were not significantly affected by feeding the reduced-CP diet. In conclusion, layer performance can remain satisfactory on reduced-CP diets for short periods, but long-term feeding of reduced-CP diets may not be advisable because it will reduce performance in the late stage of production.     

Evaluation of bovine rumen contents as a feed for lambs

This study evaluated effects of increasing levels of dried rumen contents (DRC) on voluntary intake, growth performance, digestibility, nutritive value, N utilization, microbial protein supply (MPS), and purine derivatives excretion (PDE) of lambs fed with Afzelia africana basal forage. Sixteen lambs (13.7?±?0.1 kg body weight (BW)) were randomly assigned to one of the four eight diets containing 0, 200, 400 and 600 g DRC/kg dry matter (DM) in a completely random design. Intakes of concentrate, DM, crude protein (CP), organic matter (OM), digestible CP (DCP), digestible OM (DOM), digestible energy (DE) and metabolizable energy (ME), CP and OM digestibility, DOM, DCP, DE, ME, N intake and retention, weight gain, cost/kg BW gain, MPS and PDE increased with increasing DRC level up to 400 g/kg DRC and declined at 600 g/kg DRC (P?<?0.05; 0.01). Feed conversion ratio and DM digestibility declined as DRC level increased from 0 to 400 g/kg and peaked at 600 g/kg DRC (P?<?0.05; 0.01). Forage intake and DE/DCP ratio decreased (P?<?0.05; 0.01) progressively with increasing DRC level. Results indicate that DRC can be incorporated up to 400 g/kg in a compounded ration for sheep.     

Egg production, egg quality and crop content of Rhode Island Red hens grazing on natural tropical vegetation

The aim of this experiment was to study the suitability of the outdoor system for Rhode Island Red hens under the tropical conditions of southern Mexico. Twelve floor pens, each containing four birds, were divided randomly into two groups. The first group was raised indoors only, while each of the second group replicates had access to an outdoor area with natural-grown vegetation from 0800 to 1700 hours daily. Both groups fed ad libitum on a commercial layers diet. The results revealed no differences in body weight between treatments. The outdoor group recorded significantly higher egg laying rate (86.90 vs. 78.05 %), higher egg mass (50.66 vs. 45.30 g egg/hen/day), and higher feed intake (103.70 vs. 97.67 g/day) versus the indoor group. The outdoor group had eggs with darker yellow yolks (9.46 vs. 5.46), lower yolk, and higher albumen proportions (P?<?0.05) versus the indoor group. The crop content of the outdoor hens consisted of 86.55 % concentrated feed, 6.30 % plant material, 2.27 % grit stones, 1.69 % snails and oyster shells, 1.25 % seeds, 0.95 % farm wastes, and 0.99 % insects, worms, and larvae. Of the outdoor hens, 43.1 % was observed to be in the range at each scanning time. The outdoor system in the tropics had beneficial effects on Rhode Island Red hen performance, and the hens utilized the outdoor area effectively and obtained various feed items.     

Effect of replacing soybean protein with protein from ensiled stylo (Stylosanthes guianensis (Aubl.) Sw. var. guianensis) on growth performance, carcass traits and organ weights of exotic (Landrace × Yorkshire) and native (Moo Lath) Lao pigs

The present study examined the impact of replacing crude protein (CP) from soybean with CP from ensiled stylo (ES) on growth performance, carcass traits and organ weights in Landrace × Yorkshire (LY) and Moo Lath (ML) native Lao pigs. Twenty-four castrated male pigs, 12 of each breed, were allocated to the diet treatments according to a completely randomised 3?×?2 factorial (three ES levels × two breeds) arrangement, with four pigs per diet treatment. Pigs were kept in individual pens and fed at 4 % dry matter of body weight for 98 days. The control diet was formulated with soybean meal as the main CP source, and in the other two experimental diets, CP from soybean was replaced at 25 % (ES25) and 50 % (ES50) by CP from ES. Calculated metabolisable energy intake decreased with ES50 diet, while dry matter intake (DMI) and CP intake (CPI) were the highest in ES25 diet (P?<?0.001). Overall, average daily gain (ADG) and feed conversion ratio (FCR) were unaffected by diet treatments. Carcass weight, backfat thickness and dressing percentage were unaffected by soybean CP replacement, while the weights of lung, large intestine and stomach were higher (P?<?0.001) when 25 % of soybean CP was replaced by CP from ES. LY pigs had higher (P?<?0.001) DMI, CPI and ADG and poorer (P?<?0.001) FCR than ML pigs. LY pigs had higher carcass weight (P?<?0.001), lower backfat thickness (P?<?0.001) and higher organ weight (P?<?0.001) than ML pigs, except for small intestine weight, where there was no difference between the LY and ML pigs (P?>?0.05). In conclusion, ES can replace up to 50 % of soybean CP in the diet of growing Lao LY and ML pigs without negative effects on performance and carcass traits.     

Feeding value of different levels of malt sprout and katikala atella on nutrient utilization and growth performance of sheep fed basal diet of Rhodes grass hay

Nonconventional agro-industrial by-products such as traditional liquor residues (locally called katikala atella) are widely used by livestock farmers in Ethiopia. The objective of this experiment was to evaluate the supplementary value of katikala atella and malt sprout (MS) on performance of sheep fed a basal diet of Rhodes grass hay. Thirty intact yearling male sheep with an average initial body weight of 17.4?±?0.74 kg (mean?±?SD) were assigned to the treatments in a completely randomized block design: atella alone (T1), 75 % atella?+?25 % malt sprout (MS) (T2), 50 % atella?+?50 % MS (T3), 25 % atella?+?75 % MS (T4), MS alone (T5), and Rhodes grass hay alone (T6). Grass hay was fed ad libitum to all treatments. The total dry matter (DM) and organic matter (OM) intakes of sheep fed T4, T5, and T3 diets were the highest (P?<?0.05), while sheep receiving T6 had the lowest DM intake. The highest (P?<?0.05) total crude protein (CP) intake was for sheep fed T5 diet, while the lowest was for those fed T6 diet. Sheep receiving T3 diet had higher (P?<?0.05) DM, OM, CP, neutral detergent fiber (NDF), and acid detergent fiber (ADF) digestibility as compared with those fed T1, T2, and T6 diets. Sheep supplemented with 50–100 % malt sprout had similar (P?>?0.05) DM, OM, CP, NDF, and ADF digestibility. The highest (P?<?0.05) average daily gain was for sheep fed T3, T4, and T5 diets, while sheep in T6 lost body weight. Sheep fed T5 diet had the highest (P?<?0.05) nitrogen retention, while those fed T6 diet had the lowest. The study has shown that a mixture diet consisting of equal parts of katikala atella and malt sprout (T3) are found to be superior in most of the required nutrient characteristics.     

Effect of replacing soybean protein by taro leaf (Colocasia esculenta (L.) Schott) protein on growth performance of exotic (Landrace × Yorkshire) and native (Moo Lath) Lao pigs

The impact of replacing soybean crude protein (CP) with CP from ensiled taro leaves (ET) on growth performance, carcass traits, and organ weights in Landrace × Yorkshire (LY) and Moo Lath (ML) Lao pigs was studied. Twenty-four castrated male pigs, 12 of each breed, were allocated to the treatments according to a completely randomized 3?×?2 factorial (three levels of ET × two breeds) arrangement with four pigs per treatment. The pigs were kept in individual pens and were fed at 4 % dry matter of body weight for 105 days. The control diet (ET0) was formulated with soybean meal as the main CP source, and in the other two diets, soybean CP was replaced to 25 % (ET25) and 50 % (ET50), respectively, with CP from ensiled taro leaves. Calculated metabolizable energy intake decreased with increasing replacement of soybean CP in the diet, while dry matter intake (DMI), CP intake (CPI), average daily gain (ADG), and feed conversion ratio (FCR) were unaffected. Carcass weight, back fat thickness, and dressing percentage were unaffected by soybean CP replacement, while organ weights (except for spleen) increased (P?<?0.001) when soybean CP was replaced by CP from ensiled taro leaves in the diet. LY pigs had higher (P?<?0.001) DMI, CPI, and ADG and better (P?<?0.001) FCR than ML pigs. LY pigs had higher carcass weight (P?<?0.001), lower back fat thickness (P?<?0.001), and higher organ weights (P?<?0.05–0.001) than the ML pigs. In conclusion, taro leaf silage can replace up to 50 % of soybean CP in the diet of growing Lao LY and ML pigs without negative effects on performance and carcass traits.     

The nutritional value of peanut hay (Arachis hypogaea L.) as an alternate forage source for sheep

The aim of this study was to evaluate the nutritional and feeding value of peanut hay (Arachis hypogaea L.) produced under tropical environment as an alternate forage resource for sheep. Peanut hay was appreciably high in crude protein [CP; 105 g/kg dry matter (DM)] and lower in neutral detergent fiber (NDF; 466 g/kg DM). Moreover, peanut hay was rich in Ca (12 g/kg DM) and P (1.7 g/kg DM). A feeding trial was conducted to investigate the effect of substituting wheat straw with peanut hay on nutrient intake, digestibility, and N utilization. Four adult Ramghani (Kaghani × Rambouillet) wethers (60?±?2.5 kg body weight) were randomly assigned to the four dietary treatments according to a 4?×?4 Latin square design. The four rations were formulated on isonitrogenous and isocaloric bases and differed in the proportion (in grams per kilogram DM) of wheat straw/peanut hay, i.e., 700:0, 460:240, 240:460, and 0:700. The replacement of wheat straw with peanut hay increased the intakes of DM (P?<?0.001), NDF (P?<?0.01), and N (P?<?0.001). Moreover, apparent in vivo digestibility of DM, NDF, and CP increased (P?<?0.001) with the increasing proportion of peanut hay in the ration. Nitrogen retention in the body increased (P?<?0.01; 3.2 to 8.1 g/day) with the replacement of wheat straw with peanut hay. These findings showed that substitution of wheat straw with peanut hay can improve DM and nutrients intake, digestibility, and N retention in sheep.     

Supplementation of suckling beef calves with different levels of crude protein on tropical pasture

The effects of supplementation with different levels of crude protein on performance, intake and nutrient digestibility and efficiency of microbial protein synthesis in suckling beef calves on pasture were assessed. Fifty-five calves, with an average age of 100 days and an initial average body weight of 110?±?7.5 kg and their respective dams, were used. The experimental design was completely randomised with five treatments and 11 replications. The experimental treatments for calves were as follows: control = calves received only mineral mixture; supplementation levels = calves received supplement containing 8, 19, 30 or 41 % of crude protein (CP, at a rate of 0.5 % of body weight (BW)). The cows received only mineral mixture ad libitum. Supplemented calves had higher (P?<?0.1) average daily gain (ADG). Protein levels showed a quadratic effect (P?<?0.1) on average daily gain (ADG) of calves. There was no difference in total dry matter (DM) intake (P?>?0.1). However, intake of dry matter forage (DMF) presented cubic profiles (P?<?0.1), with CP levels in the supplements. Supplementation increased (P?<?0.1) the digestibility of nutrients, except for the digestibility of neutral detergent fibre. Supplementation increased (P?<?0.1) the production of microbial nitrogen and N losses in urine. It can be concluded that multiple supplementations optimise the performance of beef calves on creep feeding. The intake of supplements with CP levels between 8 and 30 % partially replaces of the pasture ingested by calves and increases the digestibility of the diet.     

Effect of phase-feeding crude protein on performance and carcass characteristics of crossbred beef bulls: an application to reduce nitrogen compounds in beef cattle diets

Beef cattle (24) with an average initial body weight of 417?±?54 kg were assigned in a 2?×?2 factorial design with six repetitions. The factors studied were two levels of CP: 11 (low CP) or 13 % (high CP) in the initial feedlot phase (days 1–36) and in the final phase (days 37–72). After 36 days, half of the bulls fed with each level of CP were selected to reverse the CP level. No interaction was observed (P?>?0.05) between the level of protein in the initial and final phases on the intake of the nutrients evaluated. There was no effect (P?>?0.05) of the protein levels in the initial and final phases on intake of dry matter, organic matter, CP, non-fiber carbohydrates, and total digestible nutrients. No differences were observed among treatments (P?>?0.05) for average daily gain (X = 1.99 kg/day) and carcass traits. We conclude that it is possible to feed Holstein-Zebu crossed bulls with an average daily gain of approximately 2 kg using a fixed level of 11 % CP during the entire feedlot period, and this diet is economically viable and environmentally sound.