Effects of dietary inclusion level of a phytogenic premix on broiler growth performance, nutrient digestibility, total antioxidant capacity and gene expression of antioxidant enzymes

The inclusion level of a phytogenic premix (PP) (Anco FIT  Poultry) was studied for its effects on broiler growth performance, nutrient digestibility and total antioxidant capacity (TAC) of meat and liver. In addition, gene expression of antioxidant enzymes CAT, SOD and GPx was profiled along the broiler intestine.

A total of 500 one-day-old Cobb broiler chickens were assigned into 4 treatments, with 5 replicates of 25 chickens each. Basal diets were formulated to meet starter (1 to 10d), grower (11 to 22d) and finisher (23 to 42d) growth phase requirements. Depending on PP inclusion level (0, 750, 1000 and 2000 mg/kg diet), treatments were: PP-0, P-750, PP-1000 and PP-2000. Feed and water were available ad libitum.
Data were analyzed by ANOVA, taking the treatment as fixed effect. Statistical significant effects (P≤0.05) were further analyzed and means were compared using Tukey HSD test. In addition, polynomial contrasts tested the linear and quadratic effect of PP inclusion levels.

Growth performance responses did not differ (P>0.05) between treatments. However, there was a trend (P=0.089) for improved FCR by 4.5% in PP-1000 compared to PP-0 at the finisher phase. In addition, trends for improved European production efficiency index were seen for PP-1000 during the finisher phase (P=0.087) and overall (P=0.057). Treatment PP-1000 had the highest carcass (P=0.030) and breast fillet yield (P=0.023). From the digestibility study, PP-1000 had higher AMEn (P=0.049) compared to treatments PP-2000 and PP-0.

The PP inclusion level resulted in higher breast (P=0.005), thigh (P=0.002) and liver (P=0.040) TAC. In particular, breast and thigh TAC increased in a quadratic pattern and reached plateu at PP-1000, whereas liver TAC continued to increase linearly. Gene expression of SOD was significantly up-regulated in the duodenum (P=0.027), jejunum (P=0.026) and ceca (P=0.023) in PP-1000 and PP-750 compared to PP-0. In ceca, CAT expression displayed a quadratic pattern of up-regulation (Pq=0.053) in the same direction with SOD (Pq=0.006).

Overall, this study provides evidence for potential PP-1000 benefits for carcass and breast fillet yield, energy sparing and overall antioxidant capacity in broiler gut and meat.

Researchers of this study

published in the proceedings of the scientific forum IPPE 2018

Konstantinos C. Mountzouris*, Vasileios Paraskeuas*, Eirini Griela*, Andreas Kern# and Konstantinos Fegeros*
*Department of Nutritional Physiology and Feeding, Agricultural University of Athens, 118 55 Athens, Greece
#Anco Animal Nutrition Competence GmbH, Linzer Strasse 55, 3100 Sankt Poelten, Austria

One additional incentive for proper silage management

There are many factors mentioned in textbooks, which you can control to maximize the quality of your corn silage with proper silage management. The timing and conditions at harvesting corn silage as well as minimizing the exposure of silage to oxygen during storage to avoid spoilage are crucial to for the nutritional value of the silage to the dairy cow.

What the textbooks don’t tell you is that a lot of those factors can also contribute to the formation of mycotoxins if not practiced properly. Mycotoxins are produced under favourable conditions by certain types of moulds. However, the hidden danger can be that mycotoxins are present without clear visual signs of mould in the silage.

Quality of 2017 corn silage

Read about what you should know about 2017 corn silage here.

Symptoms for a mycotoxin challenge

Typical symptoms of a mycotoxin challenge in a dairy herd are:
• decreased feed intake,
• reduced milk and milk component yields,
• increase in somatic cell counts
• reduced reproductive performance, including decreased conception rates, increase in irregular heats and ovarian cysts.
• increased incidences of metabolic disorders such as ketosis, retained placentas, displaced abomasum

Providing those symptoms cannot be explained by other nutritional or management short-comings on the farm, the cause are most likely mycotoxins in the feed ration.

Economic impact

Subclinical mycotoxicoses decrease profitability by lowering milk production and quality while increasing expenses from inappropriate veterinary therapies.

So, the risk of mycotoxins is one more incentive for best practice at harvesting and storing corn silage.

Mycotoxins produced in corn silage

Mycotoxins can already accumulate in the crop prior to silage making during growth of the corn on the field and often will not be visible. This level of toxin can then continue to increase during poor harvest conditions and on into storage. The primary toxin producing fungi on corn in the field includes Fusarium.

Several mycotoxins of concern are produced by Fusarium and include:

deoxynivalenol (DON),

zearalenone

and T-2 toxin.

Zearalenone is a mycotoxin, which can cause fertility problems after its ingestion due to its structure being very similar to the hormone oestrogen. DON can have a negative impact on rumen efficiency and hence on milk solid yields. Read more about DON in dairy cows in the following link  How cows can adapt to DON

Frost increases risk of mycotoxins in silage

Corn silage harvested after frost is at even greater risk of toxin contamination. When the corn is chopped and placed in a silo, the frosted and now drier silage is difficult to pack properly. The oxygen level in the silo takes longer to deplete during tilling and the fungus can continue to grow and produce toxin for several days.

Mycotoxins in grass silage

Mycotoxins, such as zearalenone, have also been found in grass silage, however the levels are generally much lower than on corn silage (Driehus et al 2009)

 

Managing the risk of mycotoxins in silage

Pre-harvest events

While silage-making practices impact fungi and mycotoxin levels, environmental conditions likely have the largest impact Environmental conditions, such as excessive moisture, temperature extremes, drought conditions, insect damage, crop systems and some agronomic practices, can cause stress and predispose plants in the field to mould and determine the severity of mycotoxin contamination.

Despite progress made in prevention through breeding of resistant varieties and improvement in agronomic practices hazardous concentrations of mycotoxins may occur as a result of annual weather fluctuations.

Post-harvest management

Excellent silage management can reduce the incidence of mycotoxins. Prevention of mycotoxins in silage includes following accepted silage making practices aimed at preventing deterioration, primarily by quickly reducing pH and the elimination of oxygen (Figure 1 below). This decreases the growth of moulds and mycotoxin contamination.

Figure 1 The 3 major events that make good silage and factors that can affect silage fermentation
(Kung 2000, Tangni et al 2013)

silage management - anco

DM content

DM content of the forage can have major effects on the ensiling process via a number of different mechanisms.
1) Drier silages do not pack well and thus it is difficult to exclude all of the oxygen from the forage mass during the confection of the silo.

2) As the DM content increases, growth of lactic acid bacteria is inhibited and the rate and extent of fermentation is reduced.

3) If the forage is too moist and pH decline is not sufficient, clostridia, which ferment lactic to butyric acid and amino acids to ammonia, might become active. This process results in increases in pH and losses of silage DM content.

Rapid feed-out

When the silo is opened for feeding, oxygen becomes available to the front of the mass and the activity of the yeasts and molds, as a result of survival of fungal spores or a re-colonization of these microorganisms, could reduce aerobic stability of ensiled mass, thus favoring potentially toxigenic fungi development. Silo size should be matched to herd size to ensure daily removal of silage at a rate faster than deterioration. In warm weather, it is best to remove a foot of silage daily from the feeding face. The feeding face of silos should be cleanly cut and disturbed as little as possible to prevent aeration into the silage mass. Silage (or other wet feeds) should be fed immediately after removal from storage. Spoilage should not be fed and feed bunks should be cleaned regularly.

Silage Inoculants

As part of the best ensiling practices the use of an appropriate silage inoculant, depending on various conditions, should be considered.

Regular monitoring
Monitoring the forage quality during the preservation process is the only real way to assess the given situation.

 

References

Cheli et al 2013. Fungal populations and mycotoxins in silages: From occurrence to analysis 

Driehuis et al 2009. Occurrence of mycotoxins in maize, grass and wheat silage for dairy cattle in the 

Gallo et al 2015. Review on Mycotoxin Issues in Ruminants: Occurrence in Forages, Effects of Mycotoxin Ingestion on Health Status and Animal Performance and Practical Strategies to Counteract Their Negative Effects

Tangni E. K., Pussemier L. and Van Hove F. 2013, Mycotoxin Contaminating Maize and Grass Silages for Dairy Cattle Feeding: Current State and Challenges, J Anim Sci Adv 2013, 3(10): 492-511

 

2017 Corn silage: 3 things you should know

Corn silage for both beef and dairy fluctuates between 8-10% of the total corn acres in the US: This year’s corn silage can be expected not to be typical, due to challenging weather conditions that prevailed across different states in 2017.

High variability in quality. Depending on the state, severe drought, heat stress or wet conditions will have a great impact on the quality of 2017 corn silage

Extra sampling is recommended. Due to high variability in the quality of corn silage, producers need to take extra samples after fermentation to track quality levels and the amounts of digestible starch (target for starch content over 30 percent), 30-hour neutral detergent fiber digestibility (target over 55 percent) and 30-hour undigested neutral detergent fiber (target under 45 percent).

In addition to testing for quality and starch, tests should also include mycotoxin analysis due to the higher risk of contamination in 2017 corn silage. Testing results can help when building plans to optimize the crop and the ration.

Check out this video for tips on how to prepare a representative silage sample.

Video on preparing representative silage samples

High levels of mycotoxins have already been reported in 2017 corn in several states in the US. DON levels > 5ppm have been reported in South Dakota, Nebraska, Wisconsin, New York and Pennsylvania corn, whereas aflatoxin levels greater than 100ppb have been reported in Georgia, Texas, North Dakota, Nebraska and Oklahoma. According to the 2003 USDA Crop Production Report, the top ten corn silage producing states are: WI, NY, CA, PA, MN, IA, SD, NE and ID.

For an update on Mycotoxins in 2017 crops and technical information on how cows adapt to DON please watch the video below.

 

Reports of DON contamination in US 2017 corn are increasing

As corn harvest advances in the US, reports show that the amount of corn in poor to very poor condition is well over that of last year. Also, high levels of DON are reported in corn in several states.

Minnesota, Pennsylvania have reported DON levels of greater than 1 ppm in corn silage, whereas levels of DON in corn silage in Iowa were greater than 2ppm

 

Aflatoxins: Did you know that in high yielding dairy cows the carry-over rate into milk is greater?

Researchers from Cornell University studied the relationship between the carry-over rate of aflatoxins in milk in dairy cows and the level of milk production. Their findings suggest that the current regulations of 20 ppb total aflatoxin levels allowable in dairy cow feed are not protective to avoid violation of the 0.5 ppb AFM1 regulatory levels for milk in high-producing cows.

A factor, that is considered to be important for influencing regulatory limits of both total aflatoxin and AFM1 is the rate at which AFB1 is converted and excreted as AFM1 into the milk of dairy cows.

The problem is that most previous studies on the carry-over of aflatoxins from feed to milk were in what would be considered today as low-yielding dairy cows, where the carry-over of the ingested AFB1 is closer to 1 to 2%.

However, a study carried out by Churchill et al (2016) at Cornell University revealed that the carry-over rate into milk in high yielding dairy cows is closer to 6.5%.

When linear regression was used to calculate the relationship between ingested and excreted concentrations of aflatoxin and AFM1 in milk of high yielding dairy cows, the results suggested that an aflatoxin level of 15 ppb, was the maximum likely to produce milk with aflatoxin below the US regulatory limits (0.5 ppb AFM1 in milk). Currently the FDA guidelines for aflatoxin (AFB1) in feed for dairy cows is at 20ppb.

Find out more about the carry-over rate of aflatoxins into milk in dairy cows at the end of the video below

 

How cows can adapt to DON – Anco article in milling and grain magazine

Ruminants are regarded as quite resistant to fusarium mycotoxins such as deoxynivalenol (DON) because of the detoxifying potential of rumen microbes. However, the detoxification capacity of rumen microbes depends on a functional rumen. Detoxification capacity for DON by rumen bacteria can be compromised in high producing dairy cows, which are fed greater amounts of concentrates and where feed passage rate is high.

Read more about how to best support them by nutritional means.
In “How cows can adapt to DON” published in Milling and Grain Magazine, September 2017, p 70-71  here

Read ANCO’s article in International Dairy Topics

3 ways to reduce the impact of DON on milk profits, International Dairy Topics, July 2017

Due to their high feed intakes and high concentrate: forage ratios in diets, high producing dairy cows are at risk for negative impacts of the mycotoxin deoxynivalenol (DON) on milk quality and component yields. The extent of the negative response can be managed by nutritional means, through the use of certain phytogenic substances for more consistent milk component yields and low somatic cell counts (SCC).

DON, the most prevalent mycotoxin in animal feedstuffs globally, has been shown to have a negative impact on rumen efficiency. Scientific studies reported that DON negatively impacted certain aspects of rumen fermentative capacity, especially reduced acetate and propionate production. Other reports show negative impacts on SCC in milk.

Find out how plant extracts can help to increase the resistance in dairy cows to DON by nutritional means in an article published in international dairy topics here.

First indications from 2017 US crop reports show that a wet spring and severe draught conditions are affecting grain quality and DON prevalence. Poor to very poor ratings for corn are twice as high compared to last year. Any level of mycotoxins present in corn can be expected to be three times as high in corn DDGS.

Currently 7.6% of corn is being displaced by corn DDGS in livestock rations. The substantial increase in the availability of corn distillers grains has also increased the interest in using these feeds in dairy cattle rations.

A short video by ANCO provides more information on feeding corn ddgs to dairy cows in the link to the article Feeding dairy cows DDGS with confidence.

Feeding corn ddgs to dairy cows with confidence

Rapid expansion of fuel ethanol production capacity has resulted in 36% of Corn being used for ethanol and corn ddgs production in the US today.

This lead to 7.6% of corn currently being displaced by corn distillers grains in livestock rations. The substantial increase in the availability of corn distillers grains has also increased the interest in using these feeds in dairy cattle rations.

Today corn DDGS is found in around 46% of US dairy cow rations. Corn distillers grains can be highly beneficial in formulating cost-efficient rations for high producing dairy cows.

However, with DDGS from 2016 corn greater care needs to be taken to ensure that dairy rations remain profitable. 2017 corn could also be problematic when used as corn distillers grains according to some of the early indicators from July 2017 crop reports.

Find out more in the video below.

Read Anco’s first publication in Pig Progress on gut agility

Anco article published in Pig Progress Magazine

Being able to manage all the risks impacting cost-effectiveness of diets is the holy grail of nutrition. But where best to start – controlling all the risks in the diet or enabling the animal to respond in an effective way to potential risks? Combining inspiration from the industry 4.0 movement with learnings from genetics pave the way to new approaches in pig nutrition.

Read more in: Keep pigs agile to manage the cost-effectiveness of feed by Gwendolyn Jones, Pig Progress, May 2017

Link to online version of the article
http://www.pigprogress.net/Nutrition/Articles/2017/5/Keep-pigs-agile-to-manage-the-cost-effectiveness-of-feed-121496E/