عنوان مقاله [English]
Effect of processed Lathyrus sativus by mesh or extrude on performance, nutrients digestibility, rumen and blood parameters and body measurements in Holstein dairy calves
Background and objectives: Lathyrus sativus as a source of protein have been used in ruminants’ diet and because of similar amino acids profile to soybean meal can use instead of soybean meal in ruminants’ diets (25). Heat processing increased extent of amino acids pass into the intestine in dairy cattle fed by heat processed Lathyrus sativus (18). There is limitation information about effect of Lathyrus sativus in dairy calf performance. Furthermore, the goal of this study is evaluating effect of processed Lathyrus sativus by mesh or extrude on performance, nutrients digestibility, rumen and blood parameters and body measurements in Holstein dairy calves.
Materials and methods: Eighteen Holstein female dairy calves with an average birth weight of 40 ± 3 kg were allocated randomly in complete randomized design. The experimental treatments consisted of: 1) control diet without Lathyrus sativus, 2) diet containing powder Lathyrus sativus, and 3) diet containing extruded Lathyrus sativus. The calves were fed colostrum for 3 first days after berthing and followed by equal of 10 % of their body weight milk up to 80 days. Sampling of feed, residual feed, feces, rumen fluid, blood and measuring of body weight and other measurements were done in particular times. Data were analyzed using GLM procedure of SAS using a completely randomized design with 6 replications.
Results: Starter intake in the calves fed by extruded Lathyrus sativus than those of fed mesh Lathyrus sativus and control group was significantly increased (P= 0.043), but Starter intake in the calves fed by mesh Lathyrus sativus than control group was numerically higher (P>0.05). Average daily gain, final body weight and feed efficiency were not affected by experimental treatments (P>0.05). Digestibility of dry matter, organic matter, crude protein, natural detergent fiber, acid detergent fiber and ether extract were not statistically affected among treatment (P>0.05). PH value was not affected by experimental treatments (P>0.05), but rumen ammonia nitrogen concentration using extruded Lathyrus sativus than mesh form or control group was significantly decreased (P= 0.049). There were not any different (P>0.05) in blood glucose, triglyceride, total protein and cholesterol in claves during the experiment. Also, body measurements include body length, hip height, hip width, heart girth, body barrel and withers height in the middle and end of the experiment were not affected significantly (P>0.05).
Conclusion: Using of Lathyrus sativus grain may replace soybean meal in starter diets until 80 days of age without harming growth performance. Extruding of Lathyrus sativus grain than mesh form leads to improve of feed intake and average daily gain at the end of experiment. It seems with reducing of ammonia nitrogen in the rumen and blood, extruding of Lathyrus sativus grain can pass the protein into the intestine and improve nitrogen utilization efficiency.
Key words: Lathyrus sativus, Extrude, Mesh, Performance, Holstein dairy calves.