The wolf is a top predator in the food chain, and a large part of its diet are wild ungulates, namely roe deer, red deer and wild boar. By preying on these wild species, wolves can help control diseases in the ecosystems in which they are present, as they are more likely to prey on sick or more fragile animals, thus reducing the risk of possible transmissions to livestock and humans.
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References:

Barja, I. (2009). Prey and Prey-Age Preference by the Iberian Wolf Canis Lupus Signatus in a Multiple-Prey Ecosystem. Wildlife Biology, 15: 147-154. https://doi.org/10.2981/07-096
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Figueiredo, A. M., Valente, A. M., Barros, T., Carvalho, J., Silva, D. A. M., Fonseca, C., Carvalho, L. M., & Torres, R. T. (2020). What does the wolf eat? Assessing the diet of the endangered Iberian wolf (Canis lupus signatus) in northeast Portugal. PloS one, 15(3), e0230433. https://doi.org/10.1371/journal.pone.0230433
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Projecto LIFE MED-WOLF (2016). O LOBO-IBÉRICO EM PORTUGAL - Situação no Leste da Beira Interior. LIFE MED-WOLF. https://grupolobo.pt/images/Documentos/CaoGado-Docs/Folhetos/Brochura_MED-WOLF_online.pdf
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Tanner, E., White, A., Acevedo, P., Balseiro, A., Marcos, J., & Gortázar, C. (2019). Wolves contribute to disease control in a multi-host system. Scientific reports, 9(1), 7940. https://doi.org/10.1038/s41598-019-44148-9

The wolf, like any other living being, is part of our ecosystems and plays an important role in maintaining the natural balance in the habitats it inhabits. Like all other wild animals, the wolf has the right to coexist in the landscapes shared with humans, as an integral element of ecosystems.

Declaration of Principles for Wolf Conservation‍

Humans and wolves can coexist in the same ecosystem if measures are taken to prevent damage to livestock, ensure compensation for losses and incentivise the recovery of natural habitats and the abundance of wild prey. It is important to work together with communities to create solutions that help people, such as ensuring that farmers receive help for their damage losses. In order to coexist with wolves and other predators, it is therefore necessary to combine conservation tools with measures to support local populations.

Among the various existing prevention measures (zootechnical, non-lethal, lethal), the use of livestock protection dogs (zootechnical) and fencing (non-lethal) are among the most effective and have the best effect on reducing damage and losses.
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The livestock guarding dog is considered one of the most effective methods for protecting livestock from attacks by large carnivores and also from attacks by stray dogs. They can protect any type of livestock including sheep, goats, cows, pigs, horses, donkeys and poultry. Their presence makes the animals feel protected and able to express normal behaviour, thus reducing reproductive losses. It has been found that sheep move more and utilise the pasture better with cattle dogs than without them. Cattle attacks trigger the animals' stress response, leading to inhibited reproduction, lower fertility and a greater number of abortions.
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References:

Eklund, A., López‐Bao, J.V., Tourani, M., Chapron, G., & Frank, J. (2017). Limited evidence on the effectiveness of interventions to reduce livestock predation by large carnivores. Scientific Reports, 7.

Iliopoulos, Y., Sgardelis, S.P., Koutis, V., & Savaris, D. (2009). Wolf depredation on livestock in central Greece. Mammal Research, 54, 11-22.

Lorand, C., Robert, A., Gastineau, A., Mihoub, J., & Bessa-Gomes, C. (2022). Effectiveness of interventions for managing human-large carnivore conflicts worldwide: Scare them off, don't remove them. The Science of the total environment, 156195.

Oliveira, T., Treves, A., López‐Bao, J.V., & Krofel, M. (2021). The contribution of the European LIFE program to mitigate damages caused by large carnivores in Europe. bioRxiv.

Rust, N.A., Whitehouse-Tedd, K.M. and MacMillan, D.C. (2013), Perceived efficacy of livestock-guarding dogs in South Africa: Implications for cheetah conservation. Wildl. Soc. Bull., 37: 690-697. https://doi.org/10.1002/wsb.352

Fact: The wolf avoids contact with people because it has been persecuted for centuries. There are no records of wolf attacks in Portugal and the last attack in Europe was more than 40 years ago. The only records date from the 20th century and refer to wolves with rabies, a disease that has since been eradicated from our country. All animals, wild and domestic, are dangerous when they feel attacked or persecuted, and the wolf is no exception.

Fact: The wolf evolved to hunt agile and/or large-horned prey, which fled and/or confronted packs, having developed highly effective defence strategies. Examples of such prey are the extinct aurochs, wild boar, deer, etc. However, this is not the behaviour of cattle, with the exception of ancestral indigenous breeds such as the Maroon cow. Small ruminants, particularly sheep, lack defensive strategies and this makes it easier for the wolf to kill more than one animal when it attacks. It is not doing this ‘for pleasure’, but rather with a view to saving the dead animals for times of scarcity. In a natural ecosystem, corpses that are not immediately consumed by the wolf become food for other animals such as vultures or bears.

Fact: Research studies carried out in the Iberian Peninsula and Europe, in rural landscapes, show that larger, stable packs are able to hunt larger prey. Few wolves or inexperienced wolves are more likely to hunt livestock because it's easier. In countries where wolf hunting is allowed, there have actually been increases in attacks on livestock after controlling populations. This is because packs are families made up of parents and offspring and the lack of parents, who have the knowledge and experience of hunting, causes the offspring to disperse and feed on what is easier to hunt, cattle in this case.

Fact: The myth that there are wolf releases has spread far and wide, creating mistrust and animosity. Wolves have never been introduced to the Iberian Peninsula or Europe, and there is no plan to do so. The release of wild animals is subject to prior authorisation by the country's authorities and must have a legal framework. Neither the Action Plan for Wolf Conservation in Portugal nor the conservation plans for Spain include these measures.
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The belief that the wolves are introduced is explained by the fact that they are returning to many places from which they disappeared decades ago, and the populations look on with suspicion and wonder how this could be happening. The reason is that young wolves, when they reach the age of 2, leave their original pack in search of territory. In this search, they travel dozens of kilometres a day and may stay temporarily in various places before settling in one area and forming a pack. For example, there are wolves from Italy that are arriving in Catalonia via the Pyrenees, as well as wolves from the Gredos that enter Extremadura and wolves from Viseu that reach the districts of Guarda and Castelo Branco.

Fact: Wild boar is the wolf's main prey on the Iberian Peninsula, along with roe deer and red deer. Packs frequently hunt wild boar and control their abundance, as well as reducing the risk of diseases such as tuberculosis spreading.