BACKGROUND: Phosphorous is an essential nutrient for poultry. Receiving too much phosphorous by livestock and excretion of excess phosphorus, can lead to environmental pollution. OBJECTIVES: Determining the ileal and total tract digestibility of phosphorus and calcium in di-calcium phosphates produced in Iran. METHODS: A total of 720 day-old male Ross 308 broilers were randomly divided into 8 treatments with 6 replicates of 15 birds in each. In control treatment phosphoric acid was used as a source of phosphorus. The other dietary treatments included one of the seven domestic samples of di-calcium phosphates (A to G). Chromium oxide was used as a marker in the diets. On day 21, after collecting of feces, all birds were slaughtered via neck dislocation. Then, the last one-third of ileum was removed. The contents of the intestine were collected for each replicate and after drying were sent to the laboratory to determine the chromium oxide, phosphorus, and calcium amounts. Percentage of ileal and total tract digestibility of phosphorus and calcium for each sample were calculated separately. RESULTS: The effect of type of di-calcium phosphate samples in feed on ileal and total tract digestibility of calcium and phosphorus was highly significant (p < /em> < 0.001). Ileal digestibility in control was 69.8 percentage, while the lowest was observed in the E and F samples, and the highest value was related to sample A. Digestibility for phosphorus in control diet was 53.4 percentage throughout gastrointestinal tract. The lowest amounts of total tract digestibility of phosphorus were observed in treatments E and F, respectively, while the highest total tract digestibility was related to treatment A with 47.9 per cent. CONCLUSIONS: It could be concluded that ileal digestibility is more accurate in evaluating phosphorus bioavailability and sample A had the highest biological value, while the lowest was related to the samples E and F.

Two experiments were conducted to evaluate the effect of the level and degradability of crude protein (CP) on the digestive metabolism and productive performance of dairy cows. In both experiments, 15 Holstein cows with 585 ± 40 kg of body weight were distributed in a Latin square design with five contemporary squares, three periods of 21 days and three treatments. In experiment 1, treatments consisted of three CP levels (130, 160 or 180 g CP/kg DM), while in experiment 2, the treatments consisted of three levels of rumen degradable protein (RDP; 80, 100 or 120 g RDP/kg DM) in diets with average of 163 g CP/kg DM. Variables evaluated in both experiments were dry matter intake (DMI), total apparent digestibility, milk yield (MY) and composition, ruminal fermentation and N balance. In experiment 1, the increase of CP from 130 to 180 linearly increased the organic matter, CP, neutral detergent fiber (NDF) and acid detergent fiber (ADF) intake (kg) and the apparent total digestibility coefficient of DM and CP. In addition, a linear increase of MY, fat corrected milk (FCM) and daily production of fat, protein, lactose, casein and total solids was observed. A linear increase in ruminal ammoniacal nitrogen (NH3-N) concentration and nitrogen excretion in milk, feces and urine was also observed. However, there was no observed effect on SCFA concentration. In experiment 2, the increase of the RDP from 80 to 120 increased the DMI, MY, FCM, milk protein content and digestibility coefficient of the NDF, ADF and ethereal extract. Additionally, there was an increase in NH3-N concentration and milk nitrogen excretion. The studies indicated that the increase of CP content up to 100 g RDP/kg DM increased the DMI and the productive performance of the cows, but also increased urine N. Thus, it is desirable that the increase of the CP through the increase of the RDP is carried out up to 100 g of RDP/kg DM, since there is elimination of nitrogen, decrease of milk yield and decrease of propionic acid in values above that level.

Objective: This experiment was designed to assess the quality and to evaluate the feeding impact of moringa feed on intake, digestibility, rumen fermentation, methane (CH4) production, and milk yield. Materials and methods: According to body weight and exitentry average daily milk production, fifteen BLRI cattle breed-1 lactating cows of 3rd or 4th stage of parturition with wk 3 and 4 of calving were selected and were equally and randomly distributed into three dietary groups. One group of cows was fed a control diet (T0) consisting of 1:1 dry matter (DM) of Napier silage and conventionally mixed concentrate. The other two groups were fed a control diet by randomly replacing i) 50% (T1) or ii) 100% (T2) of its concentrate with moringa feed. The three dietary groups were balanced nutritionally based on energy and protein following the Bangladesh Standards and Testing Institution (BSTI) standard. Results: The concentrate mixture was replaced with moringa feed to increase the feed efficiency and to reduce the DM or crude protein intake (p < 0.05) per 100 kg of metabolic body weight. The T2 group flourished with the highest (p < 0.05) amount of raw milk and also 4% fat-corrected milk (4.39 and 4.59 kg/day, respectively) compared to the T0 group (3.30 and 3.49 kg/day, respec¬tively). However, it increased (p < 0.05) the concentration of total volatile fatty acid and decreased (p < 0.05) the blood and milk cholesterol, and ammonia-nitrogen (NH3-N) was reputed by adding moringa feed into the T0 group, without showing any significant (p > 0.05) change in CH4 produc¬tion, fat, solid not fat, lactose or protein content of milk. Conclusion: Therefore, moringa feed increased the productivity in dairy cows, replacing the whole concentrate diet. [J Adv Vet Anim Res 2020; 7(3.000): 521-529]