Effect of feeding chandrasoor (Lepidium sativum L.) seed on major milk constituents in Indian cows

Introduction

Milk is regarded as nature's most complete food, providing an indispensable range of nutrients essential to human health. In India, the quality and quantity of milk produced at the farm level are fundamental determinants of the quality of the final dairy product reaching the consumer. The initial quality of milk at the farm is therefore of paramount importance, as it governs the nutritive value, safety and shelf life of all downstream dairy products. With growing consumer awareness and increasing market demand for premium-quality dairy produce, there is an urgent need to enhance the productive performance of lactating animals through scientifically validated, economically feasible and ecologically sustainable strategies (Shukla, 2009) [8] . Feed supplementation with herbal and medicinal plant materials represents one of the oldest and most widely practised strategies for improving milk production in South Asia. Medicinal seeds such as fenugreek (Trigonella foenum-graecum), black seed (Nigella sativa), caraway and chandrasoor (Lepidium sativum L.) have been used as galactagoguessubstances that promote lactationin folk medicine across India, Egypt, Jordan and other countries for centuries (Abo El-Nor et al., 2007) [1] . The term 'galactogogue' describes any substance of dietary, herbal or pharmacological origin that promotes, sustains or enhances milk secretion (Salem & El-Mahdy, 2001) [7] . Chandrasoor (Lepidium sativum L.), commonly known as garden cress, is a small annual herb of the family Brassicaceae (Cruciferae).

It grows widely across Indiaparticularly in Uttar Pradesh, Rajasthan, Gujarat, Maharashtra, Madhya Pradesh and Chhattisgarhand is cultivated as a rabi season crop yielding approximately three to four quintals per acre. The seeds are small, reddish and contain an array of bioactive constituents including the alkaloid lepidine and its quaternary ammonium derivatives lepidiline A and B, glucosinolates (glucotropaeolin and gluconasturtiin), sinapin, sinapic acid, mucilaginous matter, linolenic acid (30.2%), erucic acid (3.9%), high potassium (1193 mg/100 g) and diverse vitamins and minerals (Nayak et al., 2009; Radwan et al., 2007; USDA, 2002) [5,6,11] . Lepidine and related alkaloids are reported to increase glutamic-pyruvate transaminase (GPT) and glutamicoxaloacetate transaminase (GOT) activities, thereby enhancing nutrient digestibility and assimilation at the intestinal level, which in turn augments galactogogue activity in lactating animals (Valentova & Ulrichova, 2003) [12] . Furthermore, glucosinolates present in chandrasoor are thought to influence biorumen hydrolysis and lipogenic enzyme activity in mammary tissue, thereby promoting fat and total solid content of milk (Bauman & Devis, 1994) [2] . Several reputed cattle-feed manufacturing companies in India already incorporate chandrasoor as a primary ingredient in formulated galactogogue compounds. Despite its long-standing traditional use and promising biochemical profile, systematic scientific investigations into the dose-response relationship between chandrasoor supplementation and milk quality parameters in Indian dairy cows were sparse at the time of the original study. The present paper synthesises and presents the findings of a structured feeding trial conducted by Shukla (2009) [8] at Indira Gandhi Krishi Vishwavidyalaya (IGKV), Raipur, Chhattisgarh, examining the effect of graded levels of chandrasoor seed supplementation on milk yield and the major physicochemical constituents of milk in Indian crossbred cows. The present investigation was designed with the following specific objectives: To estimate qualitative changes in major milk constituents (pH, acidity, lactose, protein, fat and total solids) following chandrasoor supplementation.

Materials and Methods

Experimental Animals and Housing

The feeding trial was conducted at Jagannath Dairy, located at Mana Road, Temri, Raipur, Chhattisgarh. Twelve Indian crossbred cows, aged four to eight years and at various stages of lactation, were selected randomly from the herd. They were divided into six treatment groups of two cows each, ensuring equivalent initial milk yield within groups. Individual groups were allotted initial daily yields of 4, 3, 4, 5, 6.5 and 8.5 litres/day respectively (T 1 -T 6 ). All cows were maintained under identical management conditions and were observed regularly by a veterinarian throughout the trial. Medical records were maintained for each animal.

Feed Formulation and Experimental Design

Chandrasoor seeds of commercial grade were procured from the local market of Raipur and incorporated into a concentrate ration. The roughage component consisted of 8 kg green fodder (maize) and 4 kg wheat straw per animal per day. The concentrate mixture comprised crushed grain (maize/barley) 25%, groundnut cake/other oil cakes 30%, wheat bran/rice bran 42%, mineral mixture 2% and common salt 1%. The experimental design is summarised in Table 1. The experiment was executed in three consecutive phases per replication cycle. Phase I Control Period (7 days): All groups fed control ration without chandrasoor supplementation. Phase II Treatment Period (7 days): Groups T 2 -T 6 received formulated concentrate supplemented with 100, 150, 200, 250 and 300 g chandrasoor seed/day respectively; T 1 remained on control ration. Phase III Residual/Withdrawal Period (45 days): All groups reverted to control ration to observe residual/carryover effects of supplementation.

Milk Sample Collection and Analysis

All cows were milked twice daily at 6:00 a.m. and 4:00 p.m. Individual milk yield records were maintained to the nearest 100 ml using a spring balance. Morning and evening milk samples were collected proportionate to yield and pooled for each group for chemical analysis. Analysis was carried out daily throughout all three phases at the Dairy Chemistry Laboratory, Department of Dairy Chemistry, College of Dairy Technology, IGKV, Raipur. pH was determined using a Systronic Digital pH metre. Titratable acidity (% lactic acid) was estimated by the method of Roy and Sen (1994) using 0.1 N NaOH and phenolphthalein indicator. Lactose content was determined by the Lane-Eynon titration method. Protein was estimated by Pyne's formol titration method. Fat percentage was determined by Gerber's butyrometric method Total solids were calculated gravimetrically by drying 5-10 ml milk samples at 98-100°C to constant weight.

Statistical Analysis

Data obtained were subjected to split-plot design statistical analysis as described by Snedecor and Cochran (1994) [9] , with phases as the main plot and treatment levels of chandrasoor seed as the sub-plot factor, with seven replications. The statistical model was: Yijk = μ + δij + Si + Tk + (SxT)ik + εijk, where Si represents the effect of the ith phase, Tk the effect of the kth chandrasoor seed level, and (SxT)ik the interaction effect. Statistical software OPSTAT was used for analysis. Significant differences among means were identified using the Critical Difference (CD) at the 5% level of significance.

Results and Discussion

Effect on pH of Milk:

The pH of milk from all treatment groups across the three experimental phases is presented in Table 2. In Phase I, pH values were essentially uniform across treatments (6.65 to 6.67), confirming homogeneity of groups at baseline. During Phase II, pH values declined marginally but consistently in supplemented groups, ranging from 6.64 to 6.65. In Phase III, pH declined further in a dose-dependent manner, reaching 6.59 in T 6 . The pooled mean pH decreased from 6.65 (T 1 ) to 6.63 (T 6 ), and the treatment effect was statistically significant (F = 7.397, P<0.01; CD = 0.0156). The slight decline in pH was accompanied by a corresponding marginal rise in titratable acidity, consistent with the inverse relationship between pH and acidity in fresh milk. The phase × treatment interaction was not significant (F = 0.513, NS), indicating that the pH effect was primarily attributable to the treatment level rather than the duration or phase of supplementation. The mild acidification may reflect enhanced microbial fermentation activity in the rumen and improved metabolic turnover in the mammary gland, both associated with higher productivity.

Effect on Major Milk Constituents

The pooled mean values of all major milk constituents across treatment groups are consolidated in Table 3, and the ANOVA summary is provided in Table 4. All major constituentslactose, protein, fat and total solidsdemonstrated highly significant dose-dependent improvements in supplemented groups. Lactose content increased progressively from 4.13% (T 1 ) to 5.24% (T 6 ) in pooled means, with the most significant jump observed between T 4 (4.67%) and T 5 (5.03%). The increase in lactose is mechanistically linked to elevated blood glucose levels resulting from enhanced liver metabolism, as proposed by Larson (1985) [4] and Nazar (1994). Lactose is the primary osmotic regulator of milk secretion, and its synthesis in the mammary gland is rate-limited by UDPgalactose availability, which is itself derived from hepatic glucose metabolism. The GPT-stimulating activity of lepidine in chandrasoor seeds (Valentova & Ulrichova, 2003) [12] likely promotes glucose turnover in hepatocytes, thereby elevating the substrate pool for lactose synthesis. Protein content increased from 3.47% (T 1 , pooled) to 3.97% (T 6 ), with T 5 recording 3.95%. The improvement in protein content was attributed to de novo synthesis in the mammary gland, facilitated by positive energy balance following improved nutrient digestibility. Tomar et al. (1995) noted a non-significant effect of chandrasoor seed on protein in Murrah buffalo when insufficient doses were used, suggesting that threshold dose matters; the present study's higher dose levels (up to 300 g/day) produced significant improvements.

Fat content rose from 3.48% (T 1 ) to 3.90% (T 6 ), with T 5 recording 3.87%. The increase in fat was attributed to enhanced lipogenic activity mediated by acetyl-CoA translocation pathways in mammary tissue. Chandrasoor contains high levels of glucosinolates (lipidine, glucotropaeolin, gluconasturtiin) that may potentiate biorumen hydrolysis mechanisms, subsequently enhancing fatty acid synthesis in mammary adipocytes (Bauman & Devis, 1994) [2] . Total solids increased correspondingly from 11.86% to 12.50% (T 6 ), reflecting cumulative improvements in all non-aqueous constituents. The T 5 treatment (250 g/day) was identified as the optimal dose on the basis of the following Phase II values: Lactose 4.56%, Protein 3.75%, Fat 3.72%, Total Solids 12.32%all significantly superior to the control and exhibiting the best risk-benefit profile relative to the higher T 6 dose. During the residual Phase III, T 5 values for lactose, protein, fat, total solids indicating a sustained carry-over effect lasting up to 45 days after supplementation withdrawal. A steady state was reached approximately on the third day of treatment, with a slight decreasing trend observed thereafter during withdrawal.

Conclusion and Recommendations

The present study conclusively demonstrated that dietary supplementation of chandrasoor (Lepidium sativum L.) seed significantly enhances the major physicochemical constituents of milk in Indian crossbred cows. The following key conclusions were drawn from the experimental findings: The optimal dose of chandrasoor seed supplementation was established at 250 g/day (T 5 ), which produced the most significant and balanced improvement in overall galactogogue activity, quality parameters. Lactose content increased significantly when T 5 dose was administered, attributed to enhanced liver metabolism and elevated blood glucose availability for mammary lactose synthesis. Protein and fat content were significantly elevated in T 5 during both treatment and withdrawal periods, reflecting improved mammary protein synthesis and enhanced lipogenic enzyme activity. Total solid content increased significantly in proportion to improvements in individual major constituents, confirming overall enhancement of milk nutritive quality. pH and acidity showed minimal but statistically significant changes (slight pH decline and acidity increase), consistent with enhanced metabolic activity and not indicating any deterioration in milk quality. A significant residual/carry-over effect was observed up to 45 days post-withdrawal, suggesting cumulative physiological benefits on mammary gland function. On the basis of these findings, a daily supplementation of 250 g chandrasoor seed per cow per day is recommended as a safe, cost-effective and efficacious natural feed supplement for improving milk production during the summer season. This recommendation is directed at dairy farmers, cattle-feed manufacturers and veterinary pharmaceutical companies. Future investigations should explore the effects of chandrasoor supplementation in different seasons, across multiple lactation stages, in buffaloes and other milch breeds, and in combination with other medicinal seeds such as fenugreek and black seed.

References

1. Abo El-Nor SAH, Khattab HM, Al-Alami HA, Salem FA, Abdou MM. Effect of some medicinal plants seeds in the ration on the productive performance of lactating buffaloes. International Journal of Dairy Science. 2007;2(4):348-355.
2. Bauman DE, Devis CL. Biosynthesis of milk fat. In: Larson BL, Smith VR, editors. Lactation: A comprehensive treatise. Vol. II. New York: Academic Press; 1994. p. 31-69.
3. El-Nor SAH, Fathy F, Abdou MMA. Yield and quality of milk and cheese in response to adding some herb combinations with or without minerals in buffaloes. Egyptian Journal of Dairy Science. 2004;32(2):377386.
4. Larson BL. Lactation. Ames: Iowa State University Press; 1985.
5. Nayak PS, Upadhyaya SD, Upadhyaya A. A HPTLC densitometer determination of sinapic acid in chandrasur (Lepidium sativum). Journal of Scientific Research. 2009;1(1):121-127.
6. Radwan HM, El-Missiry MM, Al-Said WM, Ismail AS, Abdel Shafeek KA, Seif-El-Nasr MM. Investigation of the glucosinolates of Lepidium sativum growing in Egypt and their biological activity. Journal of Medicine and Medical Sciences. 2007;2(2):127-132.
7. Salem FA, El-Mahdy MR. Effect of some medicinal plants as feed additives on nutrients digestibility, rumen fermentation, blood and carcass characteristics of sheep. In: Proceedings of the 2nd Conference on Animal Production and Health in Semi-Arid Areas; 2001.
8. Shukla A. Effect of feeding chandrasoor (Lepidium sativum L.) as feed supplement on milk yield and its major constituents in Indian cows (Master's thesis). Raipur: Indira Gandhi Krishi Vishwavidyalaya; 2009.
9. Snedecor GW, Cochran WG. Statistical methods. New Delhi: Affiliated East-West Press; 1994.
10. United States Department of Agriculture [USDA]. USDA national nutrient database for standard reference. Washington DC: Agricultural Research Service; 2002.
11. Valentova K, Ulrichova J. Smallanthus sonchifolius and Lepidium meyenii -prospective medicinal crops for the prevention of chronic diseases. Biomedical Papers. 2003;147(2):119-130.