Effect of the Use of Tomato Pomace on Feeding and Performance of Lactating Goats

Abstract

The aim of this research was to evaluate the effect of including different levels of tomato pomace (TP) on performance, blood biochemical parameters, hormones, production and composition of milk, and economic analysis of Saanen goats reared in confinement. Sixteen multiparous goats (Saanen), 21 days in milk, were randomly distributed in two Latin square 4 × 4 (four periods and four treatments), according to the inclusion levels of dehydrated tomato pomace (0%, 20%, 40%, and 60%) in the diet. This inclusion resulted in differences in the intake of dry and organic matter, as well as ether extract, crude protein, water, neutral detergent fiber, and non-fibrous carbohydrates. The inclusion of 60% TP resulted in a significant decrease of body weight (−4.42 kg) in comparison with initial body weight, while the other three treatments did not affect or increase the animal body weight (between −0.05 and +3.07 kg). The addition of 20% and 40% of TP resulted in higher milk production (around 1.5 kg day−1) than in animals from a control (1.2 kg day−1) and 60% TP (1.04 kg day−1). This increase was approximately 28% in the animals with 40% of TP inclusion. Moreover, the addition of 20% or 40% TP also improved the milk quality, which presented a higher fat amount (4.37% and 4.63% in 20% TP and 40% TP animals, respectively) than in a control (3.7%) and animals feed with 60% TP (4.02%). The feed efficiency and feed conversion did not show differences between diets. Thyroid hormones (T3 and T4) were also significantly affected by the inclusion of TP in the diet. The diet with the highest level of TP (60%) had the lowest cost per kilo among the diets evaluated. However, the use of 40% TP in animal diet presented the highest milk production and intermediate production cost.

Sustainable Valorization of Tomato Pomace (Lycopersicon esculentum) in Animal Nutrition: A Review

“…It had no effect on the ratio of conjugated linoleic acid. Mizael et al [ 18 ] found that feeding different levels of TP to lactating ewes did not affect blood biochemical indicators and thyroid hormones, feed efficiency, or feed conversion ratio, but feeding 60% of the level would reduce the body weight of the ewes. Supplementation by 20% and 40% increased milk quality and fat content, respectively.…”

“…When the tomato supplementation level was 35%, the final body weight, total weight gain, average daily weight gain, and weed intake increased significantly. Mizael et al [ 18 ] reported that, although the addition of TP to the dairy goat diet had no difference in feed efficiency and feed conversion ratio, it improved milk quality and fat content. Mohammed et al [ 19 ] found that the addition of 4% and 6% TP had no adverse effects on chicken growth performance, meat quality, or hormone secretion.…”

Strategies to Increase the Value of Pomaces with Fermentation

“…Moreover, a circular economy is one of the principles of the European Green Deal that aims to improve the efficiency of resource use and to cut pollution, for instance [16,17]. Recent publications support the potential utilization of this strategy [18][19][20][21][22][23][24]. It is also important to mention that the reutilization of residues of the food industry and the consequent development of food products are concepts supported and well-accepted by consumers [25,26].…”

A brief overview on valorization of industrial tomato by-products using the biorefinery cascade approach

“…Tomato pomace is a mixture of tomato cuticle (or peel), seeds and small amounts of pulp that remain after processing (Ventura et al, 2009). It is often used in animal feed (Mizael et al, 2020) as a source of dietary fiber, as well as B vitamins, lycopene and to a lesser extent vitamin A, for example, in California (which accounts for 95% of US production) most of the pomace is added to cattle feed for dairy farms. The alternative to use in animal feed is landfilling; this, for instance, represents the prevailing end-of-life route in the US Midwest.…”

“…In Italy, tomato pomace is either given for free to farmers or is sent to landfill, which represents an added cost of 200 euros per ton for the producing companies. Overall, the use of tomato pomace is limited by the risk of ruminal acidosis caused by pomace acidity (Mizael et al, 2020) or the high moisture content (60-80% wt.) leading to fast spoiling and pollution hazard.…”