Journal of Agricultural Science and Botany

All submissions of the EM system will be redirected to Online Manuscript Submission System. Authors are requested to submit articles directly to Online Manuscript Submission System of respective journal.
Reach Us +44 1202068036

Review Article - Journal of Agricultural Science and Botany (2021) Volume 5, Issue 5

Feed Additives in Enhancing Milk Production. A Review

Debele Guta*

Department of Animal Science, College of Agriculture and Environmental science, Arsi University, Ethiopia

*Corresponding Author:
Debele Guta
Department of Natural Animal science, Arsi University, Ethiopia
E-mail: [email protected]

Accepted on January 26, 2021

Citation: Guta D. Feed Additives in Enhancing Milk Production. A Review. J Agric Sci Bot. 2021;5(5): 056.

Visit for more related articles at Journal of Agricultural Science and Botany


Soil acidity Feed components are merchandise utilized in animal nutrients to enhance the nice of feed and the pleasant of meals from animal origin, or to improve the animals’ overall performance and In Ethiopia, dairy manufacturing relies upon especially on indigenous livestock genetic sources; extra particularly on cattle, goats, camels, and sheep.

Therefore, the results of somatotropin at the performance of lactating animals were the problem of a hobby for over 50 years. It becomes, to begin with, confirmed that injections of crude pituitary extract improved milk production in dairy cows. On the opposite hand, four factors may be considered to decide if a feed additive needs to be used: Anticipated reaction, financial go back, available research, and Field responses. But manufacturers are endorsed to significantly evaluate the fee-to-benefit ratio of each feed additive in their management structures. In normally feed additives fall into much different paperwork and can be useful in decreasing consequences of ruminal acidosis, enhancing feed efficiency, a charge of advantage, heat suppression and bloat manage to call a completely few. When nicely utilized in properly-managed surroundings, a lot of these components can improve performance and profitability extensively. This assessment discussed several feed additives used for boosting milk production.


Additives, rbST, Milk production


Ethiopia holds the largest livestock population in Africa, which estimated about 60.39 million cattle, 31.30 million sheep, 32.74 million goats, 2.01 million horses, 8.85 million donkeys, 0.46 million mules, camels 1.42 million, and 56.06 million poultry population [1]. Feed additives are products utilized in animal nutrients to enhance the excellent of feed and the excellent of meals from the animal foundation, or to enhance the animals’ performance and In Ethiopia, dairy manufacturing depends mainly on indigenous livestock genetic assets; extra Specifically, on cattle, goats, camels, and sheep. Cattle have the biggest contribution (18.2%) of the entire countrywide annual milk output, accompanied by goats (7.9%), camels (6.3%), and sheep (4.6%) [1].

Therefore, the results of somatotropin on the overall performance of lactating animals have been the subject of interest for over 50 years. It became, to begin with, demonstrated that injections of crude pituitary extracts expanded milk production in dairy cows. However, restrained quantities of local pituitary somatotropin made subject programs impractical. The advent of recombinant DNA generation allowed the production of enormously huge portions of artificial bST. Since then, several studies have been performed to peer the effect of bovine somatotropin on numerous production parameters of dairy cows [2].

Bauman mentioned that milk yield had been accelerated up to 41% with daily injections of bST [3]. Similarly, Cows modify their voluntary feed-intake to aid expanded milk-yield [4].

However, somatotropin did no longer affect the cows’ fitness and reproductive performance [5]. Coordinated changes in lots of tissues and physiological methods came about to support the will increase in the synthesis of lactose, fat, and protein within the mammary glands. Changes in the irreversible loss and oxidation charges of two key metabolites, glucose, and loose fatty acids, may want to quantitatively account for will increase in lactose and milk-fat during the support-time period administration of bST [6]. Where ever milk is made out of cows, profit margins stay very tight. This routine method's attention is concentrated increasingly more on the efficiency of feed and of animal manufacturing. The more farmers invest in high satisfactory genetics – additionally essential for maximum efficiency milk production, the greater the importance of preserving very excessive pleasant rations. Similarly, West et al. said that changes in feed-intake accounted for the growth in milk-production within the longer experiments [7]. The present review has the goal to review the effect of feed components in enhancing milk manufacturing (specially bST) of the dairy cow. Therefore this paper is needed to review the impact of feed additive in improving milk production.

Literature Review

Feed additives

Area collection of feed ingredients that could cause a preferred animal response in a non- nutrient position including pH shift, increase, or metabolic modifier [8]. Therefore, four factors can be considered to determine if a feed additive has to be used: Anticipated reaction, financial go back, available studies, and Field responses.

But manufacturers are recommended to critically evaluate the fee-to-benefit ratio of every feed additive of their management systems. Feeding strategies that optimize rumen characteristics bring about most milk production and milk issue percentages and yield. Additionally, producers who use records such as those furnished by using DHIA (Dairy Herd Improvement Association) can critically compare their nutrients and feeding management packages.

Similarly, the following have been the predicted overall performance modifications the person should count on when a feed additive is covered. They encompass: Higher milk yield (top milk and/or milk persistency), growth in milk components (protein and/or fat), and more dry matter intake, stimulate rumen microbial synthesis of protein and/or unstable fatty acid (VFA) manufacturing, growth digestion in the digestive tract, stabilize rumen environment and pH, Improve boom (gain and/or feed performance), minimize weight reduction, Reduce warmth stress effects, enhance fitness (inclusive of less ketosis, lessen acidosis, or improve immune reaction) [8].

According to Phillips, [9] the use of rbST in dairy cows is an excellent instance of the development and integration of primary research derived from numerous fields into a brand new control exercise that may impact the efficiency and profitability of milk production without adversely affecting milk high-quality or animal fitness and still have much less bad results on the environment than traditional dairying [10].

BST (bovine somatotropin)

Bovine SomatoTropin (bST) is a certainly-occurring protein produced by the pituitary gland in all cattle and performs an essential function in enhancing the production and yield of milk and milk components. Recombinant Bovine SomatoTropins (rbST), which fluctuate from their local form by several amino acids, were synthesized and manufactured using recombinant DNA techniques to increase milk production in dairy cows.

Effect of BST on milk manufacturing

Daily management of exogenous bST derived from the extracts of pituitary glands, or even the growth hormone release element from the extracts of the hypothalamus of slaughtered cows or recombinantly derived bST, the reason a better milk-yield without altering the gross composition. Almost similar outcomes of increased milk-yield in dairy cows via bST management had been reported in lots of studies [7]. According to West et al, the significance of milk yield response to rbST to be increased through 7, 19, 21, and 24% with 5, 10, 15, and 20 mg/day.

In evaluation Zhao et al, stated that milk yield response to rbST by 7 and 9% with 10.3 and 25 mg/14 days [11]. On the other hand 9, 14, and 12% milk yield becomes extended with 11.4, 22.8, and 22.9/28 days [12] and 0, 12, and 25% with 7.1, 14.3, and 21.2mg/7 days [13] 18% with 250 mg/14 days [14], 12.2 and 20.0% with250 and 500 mg/14 days and 22% with 500 mg/14 days [15].

Bauman et al, said that during an extended-term study with Holstein cows, bST remedy multiplied the average Fats Corrected Milk (FCM) yield in a dose established fashion from 23 to forty one% over control manufacturing (27.9 kg/d) in lactating cows. However, growing increments of bST display less increase [3]. On the different hand, [5] determined a 32% increase of milk-yield in cows treated with one hundred IU/ day of bST over manipulate; they also determined a sample of diminishing marginal reaction of milk-yield to increasing hormone dose. Similar consequences were pronounced by other employees.

In assessment increase in milk manufacturing of cows given bST at their top lactation become less than for the ones dealt with at mid to 2 1/3 of their lactation [6]. Schneider et al, mentioned that the cows receiving forty-one. 2 mg/d of bST in their early lactation decreased 10% more 3.5% FCM than the manipulate organization. This boom became less than that pronounced through other employees within the cows dealt with bST after their peak lactation [7].

This indicated that, even though responses to exogenous bST did occur, the reaction changed into much less than that when peak lactation. One rationalization of this become that during early lactation the reaction is probably constrained by using nutrient availability because cows have been in sizable terrible strength balance. The different viable motive for this reduced response was limited delivery of glucose for lactose as opposed to via the capability of cows to mobilize frame-reserves in assist of lactation [16].

On the opposite hand McGuffey et al, suggested that administration of bST, both with the aid of daily injections or in a sustained release vehicle [17], had no sizable differences in milk or stable corrected milk of dealt with cows. In a previous examine it became proven that bST administered through prolonged launch formation became effective in improving milk-yield and efficient efficiency of cows [3].

However, the increase in milk yield with sustained-launch formulations of rbST within a single injection c program language period will vary [13].

Additionally, Bauman explained that control factors have been diagnosed as the predominant supply of version within the importance of dairy cows' responses to rbST. These factors encompass dosage of rbST, injection c language, genetic capacity, and environmental conditions [18].

According to Phillips, cows that are higher controlled are regarded to have an extra reaction to rbST than poorly managed, and manufacturers that control their operation to maximize milk manufacturing have the greatest potential to maximize milk yield response to rbST [9].

Effect of bST on Voluntary Feed Intake

Bovine somatotropin expanded the voluntary intake of cows after several weeks of remedies [19]. This remark raised any other opportunity for the mechanism of movement for bST inside the long-term treatment. This remark supported the simple competition that an animal ate to hold power homeostasis so that every day electricity intake matched day by day power output.

On other hand, Downer et al, confirmed no exchange in Feed Intakes (FI) of dairy cows in response to rbST at 56-seven-hundred mg/14 days [20]. Similarly, Binelli et al, reported that no alternate in feed intakes at 29 mg/day thereby ensuing in extended Feed Efficiency (FE). Nevertheless, Windsryg et al. [21] working on ruminally fistulated cows at 60 days postpartum injected with 25 mg of rbST/day for six weeks, stated that three.5% FCM and milk manufacturing performance had been improved with rbST remedy whereas DM intake, ruminal probabilities of crude protein (CP), alpha-amino-N, Risky Fatty Acids (RFA), pH, total tract apparent digestibility of vitamins and cellulolytic microorganism (%) have been no longer affected by rbST, however, the general range of rumen protozoa tended to be higher with rbST. Conversely, Santos et al. showed that early lactating cows that received rbST for ninety days had lower dry depend on intake (DMI) during the first forty-five days of the test, but theefficiency of feed utilization changed into extended with rbST whilst vitamins digestibility become unaffected.

On the other hand, a boom in DMI by using 46% due to rbST (500 mg /14 days), and the graduation of the DMI lower become correlated with the start of the decrease in milk manufacturing [22] .

According to Chalupa et al, DMI has been elevated (P<0.05) through 5.4 and 8.4% for dairy cows injected with 20.6 and 41. 2 mg bST/day respectively, wherein cows began to increase DMI after four weeks of rbST remedy when rbST is administered to cows, greater nutrients are needed for the accelerated synthesis of milk protein, fats, and lactose. Chapula et al, additionally discovered that rbST-dealt with cows produced more (P<0.01) FCM in step with kg of feed ate up[23].

Additionally, McGuffy et al, said that rbST partitions energy to take advantage of manufacturing at the expense of body fats. Consequently, rbST increases the capture of nutritional nutrients in milk via decreasing the relative share of fed on nutrients wanted for protection and through partitioning vitamins into milk rather than into frame reserves [24].

Pillips, noted that the maximum crucial factor of vitamins and rbST remedy is that cows need to be fed to maximize milk yield in a given control state of affairs. Therefore, improved dietary protein and strength augmented the milk manufacturing responses to rbST at 10.3 mg/day [25].

Effect of bST on Mammary Gland Tissues

There became no proof to suggest that bST has an immediate effect on mammary gland tissues for the duration of installed lactation.

However, Peel et al,[2] said that direct infusion of bST into mammary artery did no longer affect the fee of milk-synthesis. It turned into additionally tested that bST did no longer bindto the receptors in bovine mammary tissue [26]. On the alternative hand, it becomes probable that bST affected mammary gland mechanism in a roundabout way thru stimulation of the synthesis of somatomedins or other protein-factors with the aid of the liver. These factors may then act immediately on the mammary gland. Chronic bST administration has been proven to stimulate a sizeable elevation of somatomedin concentrations via the 22nd week of treatment [2].

Similarly, Capuco et al. suggested that no changes in mammary DNA of dairy cows in reaction to rbST [27]. On the contrary Binelli et al, additionally confirmed that the whole RNA, RNA concentrations, RNA accretion, and the RNA to DNA ratio improved within the mammary tissues of cows dealt with rbGRF or rbST [28].

Therefore, they recommended that rbGRF and rbST extended the secretory capability of the mammary gland, and their moves on galactopoiesis expanded synthesis of milk in step with mammary mobile.

Similarly, Carstens et al, pronounced that remedy of rbST at 500 mg/14 days in dairy heifers expanded (P<zero.01) the proportional weight of fat-unfastened mammary parenchymal tissue by way of 82%, suggesting that rbST had a superb effect on mammary gland development and subsequently milk generating potential in dairy heifers [29].

Probiotics and Prebiotics

According to Fuller R, probiotics are feed supplements that might be added to the weight loss program of farm animals to improve intestinal microbial balance [30]. Then Chiquette et al. stated that improved production of fermentation products and milk fats percent whilst a newly isolated bacterial stress [31] changed into fed to dairy cows from three weeks prepartum to 7 weeks put up-partum. Similarly, Jacquette et al. and Ware et al.said elevatedmilk yield (18 kg/day) whilst feeding cows Lactobacillus acidophilus (2x109cells/day) compared with the management institution [32 & 33].

On the different hand, Gomez-Basauri et al, found a boom in milk manufacturing (0.73 kg/day) whilst feeding cows a mixture of L. Acidophilus, L. Casei, and Enterococcus faecium [34]. Nevertheless, Nocek et al, observed that an expanded dry count number intake (2.6 kg/day) and expanded milk yield (2.3 kg/day) with the aggregate of yeasts and microorganism of probiotics presented from 3 weeks pre-partum to 10 weeks post-partum.

In the evaluation of the usage of antibiotics as dietary modifiers, which break microorganism, the inclusion of probiotics in meals is designed to encourage sure strains of bacteria in the intestine at the expense of much fewer proper ones [35]. Besides, these microorganisms are chargeable for manufacturing of vitamins of the B complicated and digestive enzymes, and stimulation of intestinal mucosa immunity, increasing safety in opposition to toxins produced by way of pathogenic microorganisms. In ruminants, they're extra effective in controlling the diseases of the gastrointestinal tract of younger animals, as there's no hardship of the rumen micro-flora.

The preliminary colonization of the small gut is from the dam’s microflora and the immediate surroundings and normally consists of streptococci, E. Coli, and Clostridium welchii. When milk feeding commences, the lactobacilli grow to be the important microorganism present (Table 1).

Parameter T0, T1 T2 T2
Trial period 8.57 ± 0.24 8.95 ± 0.15 9.64 ± 0.07 9.68 ± 0.46
Milk yield on 61st day of experiment 8.70 L 9.25 L 11.20 L 11.50 L
% Increase in milk yield 1.42% 7.70% 16.71% 16.90%
Fat % Pre-trial period 3.93 ± 0.15 3.89 ± 0.21 3.81 ± 0.50 3.95 ± 0.42
Trial period 3.95 ± 0.26 4.38 ± 0.53 4.85 ± 0.06 4.91 ± 0.41
SNF % Pre-trial period 8.10 ± 0.01 8.09 ± 0.12 8.01 ± 0.28 8.09 ± 0.37
Trial period 8.09 ± 0.07 8.30 ± 0.24 8.95 ± 0.40 9.11 ± 0.05
Density (g/cub. cm) Pre-trial period 27.73 ± 0.14 27.81 ± 0.11 27.65 ± 0.09 27.69 ± 0.19
Trial period 27.71 ± 0.51 27.93 ± 0.39 28.55 ± 0.23 29.15 ± 0.01
Freezing point (-)⁰C Pre-trial period -0.519 ± 0.10 -0.501 ± 0.16 -0.521 ± 0.11 -0.532 ± 0.17
Trial period -0.518 ± 0.01 -0.530 ± 0.02 -0.573 ± 0.04 -0.607 ± 0.09
Protein % Pre-trial period 2.90 ± 0.01 2.98 ± 0.10 2.85 ± 0.14 2.89 ± 0.08
Trial period 2.91 ± 0.05 2.95 ± 0.02 3.05 ± 0.15 3.07 ± 0.03
Lactose % Pre-trial period 5.15 ± 0.33 5.11 ± 0.12 5.18 ± 0.10 4.95 ± 0.11
Trial period 5.18 ± 0.03 4.63 ± 0.23 4.38 ± 0.25 4.40 ± 0.04
Ash % Pre-trial period 0.59 ± 0.20 0.61 ± 0.16 0.60 ± 0.41 0.57 ± 0.28
Trial period 0.60 ± 0.61 0.61 ± 0.01 0.63 ± 0.03 0.60 ± 0.04

Table 1. Effect of Probiotic Supplementation on Milk Yield and Milk Composition (Mean ± Standard Error.)

Conclusion and Recommendations

In normally feed components fall into many one-of-a-kind bureaucracies and can help decrease consequences of ruminal acidosis, enhance feed performance, a charge of advantage, warmness suppression, and bloat manipulation to call a completely few. When well utilized in well-managed surroundings, many of these components can improve performance and profitability drastically. This overview mentioned several feed additives used for reinforcing milk production.

Specifically, the rbST has a galactopoietic effect which improves milk manufacturing in dairy animals without damaging effect on milk pleasant or animal health and replica. The rbST will increase the capture of dietary nutrients in milk with the aid of decreasing the relative share of fed on vitamins wanted for upkeep and by using partitioning nutrients into milk in place of into body reserves.

Therefore, the main impact of rbST was decreased frame fat reflecting the partitioning of calories with the aid of rbST to milk on the rate of fats deposition. Therefore, the following recommendation changed into put forward:

➢ The use of BST ought to haven't any destructive influences on the surroundings so we can use it well.

➢ The use of a few feed additives becomes no longer posted in detail and there may be no enough record.

➢ Further observation may additionally want to sufficiently report some feed components in our united states.


Get the App