R. Buragohain

Influence of short-term Leucaena leucocephala feeding on milk yield and its composition, thyroid hormones, enzyme activity, and secretion of mimosine and its metabolites in milk of cattle

Four Karan/Friesian crossbred (Holstein×Tharparkar) dairy cows in late lactation (>200 days) were fed a basic diet of green maize and concentrates with an increasing proportion of Leucaena leucocephala (leucaena) leaf meal (LLM). The proportion was gradually increased from 0·25 of the dry matter intake (DMI) in the first week to 0·50 in the second, 0·75 in the third and ad libitum in the fourth week. Mimosine, 3,4-dihydroxy pyridine (3,4-DHP) and 2,3-dihydroxy pyridone (2,3-DHP) levels were determined in milk, serum, urine and faecal samples. On average DMI of leucaena was 0·023–0·025, 0·025–0·027, 0·027–0·028 and 0·022–0·025 of live weight (LW) during the first, second, third and fourth week, respectively. Mimosine, 3,4-DHP and 2,3-DHP appeared in the blood serum during leucaena feeding and continued appearing up to sixth week of experimental feeding even after the withdrawal of leucaena from the 34th day onwards. Similarly, excretion of mimosine, 3,4-DHP and 2,3-DHP were observed even after withdrawal of leucaena from the diet. The feeding of LLM resulted in a reduced level of T 3 (Triiodothyronine) and T 4 (Thyroxine) within a week of LLM feeding. The level of T 3 and T 4 improved to normal after withdrawal of LLM from the diet. The serum aspartate transferase (AST) and serum alanine transferase (ALT) activities were within the normal range. Leucaena feeding improved milk yield and composition only up to 3 weeks of feeding. The concentration of mimosine, 3,4-DHP and 2,3-DHP in milk was 0·33, 0·05 and 0·02 that of blood, respectively. The secretion of mimosine, 3,4-DHP and 2,3-DHP in the milk might be a concern for health of the offspring of leucaena-fed animals as well as human beings consuming such milk.

Growth performance, nutrient utilization, and feed efficiency in broilers fed Tithonia diversifolia leaf meal as substitute of conventional feed ingredients in Mizoram.

Aim: The study was for assessment of growth performance, nutrient utilization, and feed efficiency in broilers fed rations with varying levels of Tithonia diversifolia leaf meal (TDLM) as a substitute of conventional feed ingredients in Mizoram. Materials and Methods: A total of 180, 1-day-old broiler chicks were randomly divided into six homogeneous groups and fed rations incorporated with TDLM (TDLM at 0% [TDLM-0], 2% [TDLM-2], 4% [TDLM-4], 6% [TDLM-6], 8% [TDLM-8], and 10% [TDLM-10] level as substitute of conventional feed ingredients) for 6 weeks. The chicks were reared in battery brooders for the first 2 weeks, and thereafter, in well-ventilated deep litter house following standard management protocols. Feed and drinking water were provided ad libitum to all the groups throughout the experiment. The daily feed intake and weekly body weight gain were recorded, and a metabolic trial for 3 days was conducted at the end of the 6th week. Results: Feed consumption decreased for inclusion of TDLM but without any significant differences, except during the 3rd week where it reduced significantly (p<0.05) at and above 6% TDLM in the ration. The average body weight gain decreased significantly (p<0.05) above 6% TDLM inclusion. The average body weights at 7th, 14th, and 21st day of age reduced significantly (p<0.05) from 4% to 10% TDLM inclusion level but was statistically non-significant up to 4% TDLM at 28th, 35th, and 42nd day of age. Body weight at 42nd day of age was 1624.72±30.52, 1616.66±17.84, 1592.60±19.24, 1404.61±17.76, 1188.29±17.67, and 1054.33±18.81 gin TDLM-0, TDLM-2, TDLM-4, TDLM-6, TDLM-8, and TDLM-10, respectively. The digestibility of nutrients decreased with increased inclusion level of TDLM. The digestibility coefficient of dry matter, crude protein, ether extract, and nitrogen free extract were significantly higher in TDLM-0, but crude fiber digestibility was comparable without any significant difference among the groups. Feed conversion ratio (FCR) at 42nd day of age was 2.17±0.15, 2.17±0.15, 2.13±0.13, 2.46±0.16, 2.66±0.11, and 3.96±0.10 for TDLM-0, TDLM-2, TDLM-4, TDLM-6, TDLM-8, and TDLM-10, respectively, was statistically non-significant up to 4% TDLM inclusion level. Conclusion: Considering the insignificant effects on growth rate, FCR, and body weight at 42nd day of age, it was concluded that TDLM could be incorporated up to 4% level as substitute of the conventional feed ingredients for broilers reared under deep litter system of management in Mizoram.

Nutritional status of lactating dairy cattle under rural feeding management in Mizoram

The study was to assess nutritional status of lactating dairy cattle in Mizoram. Information on feeding management and feed-stuffs of lactating cows were collected from randomly selected dairy farmers of Bawngkawn, Durtlang and Shiphir areas of Mizoram. Study revealed use of local forest grasses and tree fodders (MGTF) with concentrate mixture (CM) to dairy cows. The average dry matter (DM), crude protein (CP) and total digestible nutrients (TDN) intakes (kg/animal/day) were 13.72±0.27, 1.57±0.03 and 6.88±0.10, indicating inadequate intakes based on body weight, milk yield and milk fat % of dairy cows. The MGTF was found rich in macro and microminerals. The digestibility of nutrients was poor including crude protein (CP) 47.26±0.80 to 52.14±0.58%, ether extract (EE) 43.49±0.93 to 49.33±0.61%, crude fibre (CF) 41.67±1.39 to 47.06±0.58. It was concluded from the study that inadequate DM, CP and TDN intakes and poor digestibility of nutrients might be responsible for poor productivity of dairy cows under rural feeding management in Mizoram.